WORKS METHOD STATEMENT
IRRIGATION WORKS
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This Method Statement provides information concerning the materials, equipment, tools and manpower and method of application to ensure compliance with contract requirements, drawings, technical specification and quality control.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not Applicable.
3.0 CONTRACTING METHODS
Since PCSB is liable for the performance of any Sub-contractor, it is vital that only companies with proven track records in the relevant activity will be engaged as Sub -contractors.
It is acknowledged that before any part of the works can be sublet, the approval of the Employer’s Representative is required.
The Conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-contractors. The conditions are bespoke for this project and therefore be required to be reflected in any form of Sub-contract utilized on the project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHODS
Please refer to PHOS-PR-010 to PHOS-PR-030 for the procurement procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower/Labour
The number of manpower/labour to be used during the activities have been identified in the Manpower Histogram.
5.2 Plant Equipment
Typical equipment to be used shall consist of:
~ Brush
~ Roller
~ Airless – spray gun
6.0 LOGISTICS PROVISIONS
The logistic control shall be in accordance with the approved Site Logistic Plan and includes wheel wash facilities and traffic management.
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Storage of Material
• These are properly labeled on both the material and the storage area to indicate the material status at all times.
• Store material in a cool, well ventilated and dry place, away from direct sunlight.
• Ensure adequate ventilated application.
• Avoid contact with skin or eyes. Any skin or eye contamination should be washed immediately with plenty of water and seek medical treatment.
• If swallowed, seek medical advice immediately. Do not induce vomiting.
• Keep away from heat sources.
• All materials are under the responsibility of the material controller and the supervisor on duty at each of the floor level.
• All material must be collected and returned to the designated storage area after working hours and properly secured and locked.
8.2 Handling of Materials
• All equipment ad materials will be handled in such a manner as not to damage the item and hence its performance.
• Purchasing will be coordinated and planned in accordance with the delivery needs of the various phases of the overall project.
• On site. Prior to the delivery, detailed and comprehensive arrangements will be made to ensure the most efficient hoisting and distribution of materials into the site areas. The schedule is divided into phases to suit the overall programme.
• This will allow materials and equipment to be marshaled just in time for the installation commencement of these phases, maximizing efficiency of delivering and minimizing storage equipment.
• All materials delivery will be carefully supervised and coordinated and proper documentation will be kept throughout the contract period. Such deliveries will be arranged in conjunction with site requirements and programs need.
• Upon delivery, material and equipment will be unloaded by crane or bottom truck with appropriate lifting capacity.
• Shifting skates/rollers and a small bottle jack may be required for final positioning. Care will be taken when towing equipment on rollers, ensuring that slings are properly secured to the base.
8.3 Surface Preparation / Requirement
• The plastering to wall, soffit and column must be of lime free smooth sponge or steel trowel finished.
• The plastering should allow a period of at least 21 days at 30ºC for curing to receive painting works with moisture content within 10 %.
• Ensure that substrate is free from moisture and water seepage or leakage.
• Before application, ensure that the substrate is free from dust, dirt and other contaminates. Any cracks or defective substrate should be repaired/replaced.
• Appropriate amsking and protecting should be carried out prior to application works.
8.4 First Aid Procedures
Skin : Wash affected skin with soap and water. Seek medical advise if irritation
persist.
Eyes : In case of contact with eyes, rinse immediately with plenty of water and seek
medical advise.
Ingestion : Give large amount of water. Do not induce vomiting.
9.0 CONSTRUCTION PHASING AND WORKFLOW
During secant wall and bored piling construction, excavation for ground anchor installation and basement formation will commence in available areas, generally moving from grids 27/H towards 1/A.
10.0 TRAFFIC MANAGEMENT AND MONITORING
The Logistic Manager and the traffic management contractor shall be responsible for the management and control of the traffic in and out from the construction site.
11.0 SAFETY PROGRAMME
Please refer to PHOS-HS-010 Health and Safety Plan.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.1 and Appendix 15.2
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan
15.0 APPENDICES
15.1 Inspection Checklist Form
15.2 Job Safety Analysis
15.3 Inspection and Test Plan
Monday, April 7, 2008
Work Methos Statement for Granite
WORKS METHOD STATEMENT
GRANITE / STONE FINISHES
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This Work Method Statement is a guidance to assist site personnel on the sequence of granite/stone works on site. It will also control and show that the applicators understand their scope of works by following the proper procedures.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not Applicable.
3.0 CONTRACTING METHODS
Since PCSB is liable for the performance of any Sub-contractor, it is vital that only companies with proven track records in the relevant activity will be engaged as Sub -contractors.
It is acknowledged that before any part of the works can be sublet, the approval of the Employer’s Representative is required.
The Conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-contractors. The conditions are bespoke for this project and therefore be required to be reflected in any form of Sub-contract utilized on the project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHODS
Please refer to PHOS-PR-010 to PHOS-PR-030 for the procurement procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower/Labour
The number of manpower/labour to be used during the activities have been identified in the Manpower Histogram.
5.2 Plant Equipment
Typical plant equipment to be used shall consist of:
~ Mechanical mixing
~ Brush
~ Roller or broom
~ Gauging water
~ Dowel pin
6.0 LOGISTICS PROVISIONS
Not Applicable
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Handling Material
1. Temporary Storage Area
• Upon arrival of the crates at the temporary storage area, check the quantity of the crates and the crate number against the purchase order and the delivery order to ensure that the correct quantity and crate number are delivered to site
• Unload the crates to the specific area in the temporary storage area
• The crates shall be stored sector by sector for retrieval when they are required to be transported to the required area
2. Installation Location
• Forklifts are employed to transport the crates to a specific where the crates will be hoisted up to the respective floor where the granite are required for installation
• At the respective floor, the crates will be conveyed to the respective installation location where they are required for installation
• Open the crates and remove the crates for installation
8.2 Installation for Floor Finishes – Semi Dry Method
1. Surface Preparation
• The RC floor slab must be aged for at least 6 weeks (preferably longer) before the cement – sand screed is laid
• The RC surface must be dry, sound and free of contamination for example grease, dust, laitance, oil and etc which might impair adhesion between cement – sand screed and RC floor slab
2. Bonding Agent
• To ensure that cement – sand screed adheres securely onto the RC slab surface, a Bonding Agent is recommended to be applied at the interface of the screed and RC floor slab
• For the purpose, mix 1 part Belle Multi Bond, latex admixture to 1.5 part of Ordinary Portland Cement (OPC) by volume
• Mix until a thin slurry consistency is obtained. Mechanical mixing is recommended. Apply bond agent onto RC surface using brush, roller or broom at thickness not more than 1 mm.
• While the bonding agent is still wet or tacky, the cement sand mortar must be immediately placed over it for best bonding results.
• Where a screed is to be constructed as an unbounded screed at thickness of 50 mm or more, a bonding agent is unnecessary. For screed in excess of 50 mm reinforcement with steel fabric / wire mesh at its mid bed is recommended to prevent curling of the screed.
3. Granite Slab Setting Bed
• For installation of white colour 1200 x 600 x 25 mm granite slabs onto matured cement sand screed at internal floor areas, use Belcem Marblefix White, a white colour, water resistant, ultra thick bed, cement based adhesive complying to BS 5980:1980 (MS 1295:1992) fpor a type 1 class AA adhesive or ANSI A 118.1 :1992
• When fixing dense granite slabs or those treated with a water repellent impregnator, Belcem Marblefex must be incorporated with Belcem Admix plus, a latex admixture in replacement of gauging water
• Apply / spread adhesive onto substrate with a thick bed solid notched trowel at trowelled thickness of approximately 6 – 9 mm.
• For large format granite slabs, a thin coat of adhesive (approximately 3.0 mm) may need to be back buttered to the granite slabs back, before it is bedded onto the spread adhesive bed. This will ensure solid bed fixing granite back in full contact with adhesive bed.
• Press or knock granites firmly onto spread adhesive bed followed by slight sliding action to ensure good contact with adhesive bed, eliminate hollow areas or air voids and to adjust the finish level.
• Apply/spread adhesive to small areas at a time (approximately 1 m2 ) to avoid surface drying (skin over) of the adhesive.
• Allow granite slab installation to set for approx 24 – 48 hours before it is subjected to light footed traffic during grouting
• Mix ratio : 6 – 7 liters Belcem Admix Plus to 20 kg Belcem Granite Fix
• Open time : approximately 15 minutes depending on atmospheric condition
• Pot life : approximately 3 – 4 hours depending on atmospheric condition
8.3 Grouting / Pointing
8.3.1 Internal Dry Areas
• Granite joints should be grouted with Belcem Fine Grout, coloured, water resistant, cement based suitable for joints up to 3 mm wide
• When grouting to internal dry areas, mix grout with clean water only. Mix with a mechanical mixer until a uniform coloured, thin creamy consistency is obtained.
8.3.2 Internal Wet Areas
• Granite joints should be grouted with Belcem Fine Grout, coloured, water resistant, cement based suitable for joints up to 3 mm wide.
• When grouting to internal wet areas, mix grout with Belcem GT Mix I, a latex admixture in replacement of gauging water. Mix with a mechanical mixer until a uniform coloured, thin creamy consistency is obtained.
• Latex modified grout offers greater resistant to penetration of water, improved durability, flexural strength, compressive strength and adhesion to side of granites.
• Allocate joints of approximately 2mm wide between granite slabs.
• Apply grout with a rubber squeegee / float and ensure that joints are fully compacted with grouting material.
• Clean excess grout promptly using a damp cloth or sponge.
• Allow grout to set for at least 24 – 48 hours (preferably longer) before granite slab installation are subjected to normal service condition.
• Mix Ratio – 8 litres Belcem GT-Mix I (Clean water) : 20 kg (1 : 2.5)
8.3.3 Movement Joints
• Movement joints must be incorporated where necessary; complying to the requirements of BS 5385 : Part 1 : 1990 : Clause 20 & BS 5385 : Part 5 : 1990 : Clause 27.
8.4 Installation for Wall Granite – Toppin Bracket System
8.4.1 General Consideration
• Granite panels shall be installed about 100mm clear of wall.
• All fixing accessories such as brackets, extension plate shall be made of aluminium, washer, bolt, nut shall be made of stainless steel grade SUS 304.
• Where C-lipped channels to be used, it shall be hot-dipped galvanized (for sub-framing).
• All SHS shall be of mild steel and hot-dipped galvanized after fabrication.
• All welding works shall be of fillet weld. Welding works done on site will be dressed off welding spatters and coated over with galvanized paint.
8.4.2 Setting Out
• Setting out shall be carried out based on reference points provided by the main contractor.
• From these reference point, the reference level is transferred to the external surface of the column / wall by using a leveling instrument. The level for the fabricated truss shall be measured by using a measuring tape. A string is tied across the two extreme ends of the elevation at the marked level for the first elevation. The level for all intermediate columns / wall marked off the taut string. This is repeated for the other elevations.
• Similarly gridlines are set out based on the control points provided by the main contractor. The gridline is marked off from the control points onto columns/walls. The grid line on the last column/wall shall be tied back to the gridline provided by the main contractor. If the tie back does not tally with the measurement in the drawing the whole sequence is checked and repeated if necessary.
• After all the levels and grid lines have been marked on each column/wall, the position of the brackets including the hole position are marked using different colours, e.g. yellow or black for restrains brackets and red for dead-load brackets.
• Marked fabricated truss/channel position on column/wall.
8.4.3 Installation
• Drill holes into column / wall to accommodate fixing accessories, using :
1. Long SST plates or L brackets are welded on to the galvanized RHS frame exactly marked for the fixing of the granite panel.
2. Position of the Toppin Back Hole Bolts are marked exactly behind the granite panel to match the location of the long SST plates or L brackets welded on the hollow section frame. Using a special machine holes are drilled behind the granite panels at the exact position, approximately 20mm in depth.
3. The back bolt is fixed and tightened with nut and washer with extension plates. This predrill back bolt granite panels will be hoisted to exact locations of the welded L angle or plate.
4. During installation, the adjustable toppin system slot hole will accommodate any adjustment required about 20mm to suit site conditions.
• Using prefabricate truss / C-channel (where the design require sub-framing) – Only when necessary or site condition confirm.
1. Insert anchor bolt into holes drilled in the column / wall / beam / floor.
2. Mount prefabricated truss / vertical C-channel and tighten nut.
3. Check verticality and alignment of truss / channel.
4. Mount bracket / horizontal channel onto predrilled hole in truss/channel by means of bolt and nut with washer. To the predrilled hole in the free length of the bracket is inserted a dowel pin. Align the bracket with the dowel pin, embedded in Tenax glue, in the predrilled holes in the granite slabs.
• Apply approved sealant to the back and sides of the granite. Allow to dry.
• Each piece of stone is supported at the back by four toppin brackets bolted to SST plates or L angle welded to the hollow section frame.
• Ensure that the first (bottom) row of granite is aligned, leveled and properly fixed o the hollow section frame.
• The next row will be installed on top of the first row of slabs.
• Check verticality and alignment of each slab.
• Leave finished work square, regular, true to line, level and plane with a satisfactory at all junctions.
• Tape a sheet of 1000g polystyrene over granite and cover with plywood to a height of 1.2m for protection of the installed granite.
9.0 CONSTRUCTION PHASING AND WORKFLOW
Not Applicable
10.0 TRAFFIC MANAGEMENT AND MONITORING
The Logistic Manager and the traffic management contractor shall be responsible for the management and control of the traffic in and out from the construction site.
11.0 SAFETY PROGRAMME
Please refer to PHOS-HS-010 Health and Safety Plan.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.1 for the Inspection and Test Plan and Appendix 15.2 for the Checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan
15.0 APPENDICES
15.1 Inspection and Test Plan
15.2 Inspection Checklist Form
15.3 Job Safety Analysis
15.4 Detail Drawing
GRANITE / STONE FINISHES
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This Work Method Statement is a guidance to assist site personnel on the sequence of granite/stone works on site. It will also control and show that the applicators understand their scope of works by following the proper procedures.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not Applicable.
3.0 CONTRACTING METHODS
Since PCSB is liable for the performance of any Sub-contractor, it is vital that only companies with proven track records in the relevant activity will be engaged as Sub -contractors.
It is acknowledged that before any part of the works can be sublet, the approval of the Employer’s Representative is required.
The Conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-contractors. The conditions are bespoke for this project and therefore be required to be reflected in any form of Sub-contract utilized on the project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHODS
Please refer to PHOS-PR-010 to PHOS-PR-030 for the procurement procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower/Labour
The number of manpower/labour to be used during the activities have been identified in the Manpower Histogram.
5.2 Plant Equipment
Typical plant equipment to be used shall consist of:
~ Mechanical mixing
~ Brush
~ Roller or broom
~ Gauging water
~ Dowel pin
6.0 LOGISTICS PROVISIONS
Not Applicable
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Handling Material
1. Temporary Storage Area
• Upon arrival of the crates at the temporary storage area, check the quantity of the crates and the crate number against the purchase order and the delivery order to ensure that the correct quantity and crate number are delivered to site
• Unload the crates to the specific area in the temporary storage area
• The crates shall be stored sector by sector for retrieval when they are required to be transported to the required area
2. Installation Location
• Forklifts are employed to transport the crates to a specific where the crates will be hoisted up to the respective floor where the granite are required for installation
• At the respective floor, the crates will be conveyed to the respective installation location where they are required for installation
• Open the crates and remove the crates for installation
8.2 Installation for Floor Finishes – Semi Dry Method
1. Surface Preparation
• The RC floor slab must be aged for at least 6 weeks (preferably longer) before the cement – sand screed is laid
• The RC surface must be dry, sound and free of contamination for example grease, dust, laitance, oil and etc which might impair adhesion between cement – sand screed and RC floor slab
2. Bonding Agent
• To ensure that cement – sand screed adheres securely onto the RC slab surface, a Bonding Agent is recommended to be applied at the interface of the screed and RC floor slab
• For the purpose, mix 1 part Belle Multi Bond, latex admixture to 1.5 part of Ordinary Portland Cement (OPC) by volume
• Mix until a thin slurry consistency is obtained. Mechanical mixing is recommended. Apply bond agent onto RC surface using brush, roller or broom at thickness not more than 1 mm.
• While the bonding agent is still wet or tacky, the cement sand mortar must be immediately placed over it for best bonding results.
• Where a screed is to be constructed as an unbounded screed at thickness of 50 mm or more, a bonding agent is unnecessary. For screed in excess of 50 mm reinforcement with steel fabric / wire mesh at its mid bed is recommended to prevent curling of the screed.
3. Granite Slab Setting Bed
• For installation of white colour 1200 x 600 x 25 mm granite slabs onto matured cement sand screed at internal floor areas, use Belcem Marblefix White, a white colour, water resistant, ultra thick bed, cement based adhesive complying to BS 5980:1980 (MS 1295:1992) fpor a type 1 class AA adhesive or ANSI A 118.1 :1992
• When fixing dense granite slabs or those treated with a water repellent impregnator, Belcem Marblefex must be incorporated with Belcem Admix plus, a latex admixture in replacement of gauging water
• Apply / spread adhesive onto substrate with a thick bed solid notched trowel at trowelled thickness of approximately 6 – 9 mm.
• For large format granite slabs, a thin coat of adhesive (approximately 3.0 mm) may need to be back buttered to the granite slabs back, before it is bedded onto the spread adhesive bed. This will ensure solid bed fixing granite back in full contact with adhesive bed.
• Press or knock granites firmly onto spread adhesive bed followed by slight sliding action to ensure good contact with adhesive bed, eliminate hollow areas or air voids and to adjust the finish level.
• Apply/spread adhesive to small areas at a time (approximately 1 m2 ) to avoid surface drying (skin over) of the adhesive.
• Allow granite slab installation to set for approx 24 – 48 hours before it is subjected to light footed traffic during grouting
• Mix ratio : 6 – 7 liters Belcem Admix Plus to 20 kg Belcem Granite Fix
• Open time : approximately 15 minutes depending on atmospheric condition
• Pot life : approximately 3 – 4 hours depending on atmospheric condition
8.3 Grouting / Pointing
8.3.1 Internal Dry Areas
• Granite joints should be grouted with Belcem Fine Grout, coloured, water resistant, cement based suitable for joints up to 3 mm wide
• When grouting to internal dry areas, mix grout with clean water only. Mix with a mechanical mixer until a uniform coloured, thin creamy consistency is obtained.
8.3.2 Internal Wet Areas
• Granite joints should be grouted with Belcem Fine Grout, coloured, water resistant, cement based suitable for joints up to 3 mm wide.
• When grouting to internal wet areas, mix grout with Belcem GT Mix I, a latex admixture in replacement of gauging water. Mix with a mechanical mixer until a uniform coloured, thin creamy consistency is obtained.
• Latex modified grout offers greater resistant to penetration of water, improved durability, flexural strength, compressive strength and adhesion to side of granites.
• Allocate joints of approximately 2mm wide between granite slabs.
• Apply grout with a rubber squeegee / float and ensure that joints are fully compacted with grouting material.
• Clean excess grout promptly using a damp cloth or sponge.
• Allow grout to set for at least 24 – 48 hours (preferably longer) before granite slab installation are subjected to normal service condition.
• Mix Ratio – 8 litres Belcem GT-Mix I (Clean water) : 20 kg (1 : 2.5)
8.3.3 Movement Joints
• Movement joints must be incorporated where necessary; complying to the requirements of BS 5385 : Part 1 : 1990 : Clause 20 & BS 5385 : Part 5 : 1990 : Clause 27.
8.4 Installation for Wall Granite – Toppin Bracket System
8.4.1 General Consideration
• Granite panels shall be installed about 100mm clear of wall.
• All fixing accessories such as brackets, extension plate shall be made of aluminium, washer, bolt, nut shall be made of stainless steel grade SUS 304.
• Where C-lipped channels to be used, it shall be hot-dipped galvanized (for sub-framing).
• All SHS shall be of mild steel and hot-dipped galvanized after fabrication.
• All welding works shall be of fillet weld. Welding works done on site will be dressed off welding spatters and coated over with galvanized paint.
8.4.2 Setting Out
• Setting out shall be carried out based on reference points provided by the main contractor.
• From these reference point, the reference level is transferred to the external surface of the column / wall by using a leveling instrument. The level for the fabricated truss shall be measured by using a measuring tape. A string is tied across the two extreme ends of the elevation at the marked level for the first elevation. The level for all intermediate columns / wall marked off the taut string. This is repeated for the other elevations.
• Similarly gridlines are set out based on the control points provided by the main contractor. The gridline is marked off from the control points onto columns/walls. The grid line on the last column/wall shall be tied back to the gridline provided by the main contractor. If the tie back does not tally with the measurement in the drawing the whole sequence is checked and repeated if necessary.
• After all the levels and grid lines have been marked on each column/wall, the position of the brackets including the hole position are marked using different colours, e.g. yellow or black for restrains brackets and red for dead-load brackets.
• Marked fabricated truss/channel position on column/wall.
8.4.3 Installation
• Drill holes into column / wall to accommodate fixing accessories, using :
1. Long SST plates or L brackets are welded on to the galvanized RHS frame exactly marked for the fixing of the granite panel.
2. Position of the Toppin Back Hole Bolts are marked exactly behind the granite panel to match the location of the long SST plates or L brackets welded on the hollow section frame. Using a special machine holes are drilled behind the granite panels at the exact position, approximately 20mm in depth.
3. The back bolt is fixed and tightened with nut and washer with extension plates. This predrill back bolt granite panels will be hoisted to exact locations of the welded L angle or plate.
4. During installation, the adjustable toppin system slot hole will accommodate any adjustment required about 20mm to suit site conditions.
• Using prefabricate truss / C-channel (where the design require sub-framing) – Only when necessary or site condition confirm.
1. Insert anchor bolt into holes drilled in the column / wall / beam / floor.
2. Mount prefabricated truss / vertical C-channel and tighten nut.
3. Check verticality and alignment of truss / channel.
4. Mount bracket / horizontal channel onto predrilled hole in truss/channel by means of bolt and nut with washer. To the predrilled hole in the free length of the bracket is inserted a dowel pin. Align the bracket with the dowel pin, embedded in Tenax glue, in the predrilled holes in the granite slabs.
• Apply approved sealant to the back and sides of the granite. Allow to dry.
• Each piece of stone is supported at the back by four toppin brackets bolted to SST plates or L angle welded to the hollow section frame.
• Ensure that the first (bottom) row of granite is aligned, leveled and properly fixed o the hollow section frame.
• The next row will be installed on top of the first row of slabs.
• Check verticality and alignment of each slab.
• Leave finished work square, regular, true to line, level and plane with a satisfactory at all junctions.
• Tape a sheet of 1000g polystyrene over granite and cover with plywood to a height of 1.2m for protection of the installed granite.
9.0 CONSTRUCTION PHASING AND WORKFLOW
Not Applicable
10.0 TRAFFIC MANAGEMENT AND MONITORING
The Logistic Manager and the traffic management contractor shall be responsible for the management and control of the traffic in and out from the construction site.
11.0 SAFETY PROGRAMME
Please refer to PHOS-HS-010 Health and Safety Plan.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.1 for the Inspection and Test Plan and Appendix 15.2 for the Checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan
15.0 APPENDICES
15.1 Inspection and Test Plan
15.2 Inspection Checklist Form
15.3 Job Safety Analysis
15.4 Detail Drawing
Work method statement for Diapharm Wall
WORKS METHOD STATEMENT
DIAPHRAGM WALL
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This submission explains the method of construction to be adopted for the diaphragm walling at the project site.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not applicable.
3.0 CONTRACTING METHOD
The conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-PCSBs. The conditions are bespoke for this project and therefore be required to be reflected in any form of subcontract utilized on this project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHOD
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower / Labour
The number of manpower / labour to be used during the activities have been identified in the Manpower Record (Weekly Progress Report).
5.2 Plant Equipment
~ Excavation Crane Liebherr 853
~ Service Crane Link Belt LS 108-BS Crawler Crane
~ 25T Mobile Crane
~ Miller Welding Machine
~ Hydraulic Excavator
~ 600mm diameter coring tools
~ 600mm Clamshell
~ Chisel TD600
~ Office / store container
~ Generator set 300kVA and 125kVA
~ Tremie pipes c/w Hopper
~ Tremie brake
~ Caviem Desander
~ Desilter
~ Desanding pump
~ 1m3 Digestuer
~ Tsurumi GPN3 Submersible pump
~ Silo
~ Mission pump
~ WSI Joint x 12m length
6.0 LOGISTICS PROVISIONS
The logistic control shall be in accordance with the approved Site Logistic Plan.
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Details of the construction method are considered according to the following matters:
1. Outline Method
2. Guide Wall
3. Bentonite
4. Soil Investigation
5. Diaphragm Wall Excavation
6. Recycling of Bentonite
7. WSI Joints (Construction Joints)
8. Placement of Reinforcement
9. Placing of Concrete
10. Diaphragm Wall Equipment
11. Report Form
12. Precautions
8.1.1 Outline Method
The Diaphragm Wall technique consist of constructing reinforced concrete walls from existing ground level by first excavation a trench by grab. During excavation, the sides of the trench are supported by bentonite slurry.
Upon completion of excavation, a steel reinforcement cage is lowered into the slurry and concrete is then poured into the trench by the tremie method.
As the concrete level rises, excess bentonite is drawn off for re-use. WSI Joints are used to form the joints between adjacent panels.
8.1.2 Guide Wall
In order to guide the grab during initial excavation for each panel and plus ensure the position and verticality of the diaphragm wall, a guide wall is constructed at around 0.5m from ground level prior to commencement of diaphragm walling. The guide wall also provides support during suspension of the reinforcement cage.(Ref. Appendix 15.4)
8.1.3 Bentonite
The bentonite GTC4 is delivered to site in 50kg per bags, which are stored under cover. The bentonite is mixed by high turbulence mixers and the slurry is stored in storage reservoirs until used in the trench.
A laboratory is provided on site for regular testing of the slurry. The minimum frequency of testing and the acceptable range of physical characteristics of the bentonite slurry are given in Appendix 15.5. Laboratory reports are kept during the construction period.
Apparatus available in the site laboratory includes the following:-
1 mud balance (density test)
1 marsh cone (viscosity test)
1 sand screen set (sand content test)
1 shearometer of Fann viscometer (shear strength test)
Paper of measuring pH
Contaminated bentonite slurry will be discarded to an acceptable dump area.
8.1.4 Soil Investigation
Prior to commencement of diaphragm walling, soil investigation holes to assess the geological conditions will be drilled/provided.
From the site investigation information, the excavation techniques are finalized and should obstructions be anticipated, the most appropriate method of treatment is planned.
8.1.5 Diaphragm Wall Excavation
8.1.5.1 General
Excavation utilizes rectangular grabs cable-operated by crane. During the excavation process, the bentonite slurry is kept to within 0.4m of the level of the top of the guide wall. The vertically of the trench is monitored by visual inspection of the crane cables during successive lowering of the grab into the trench.
The excavation crane would be maintained at a minimum distance of 4.5m from the edge of opened trench. Any movement of excavation crane will be supervised by the foreman to enforce this requirement.
Various types of panel are used, primary, successive and secondary (closing) panel.
The general arrangement of panels will be submitted separately later as shopdrawings.
8.1.5.2 Removal of Earth During Excavation
Excavated earth from the trench will be temporary stockpile on the platform and will be removed by using hydraulic excavator load into truck and dump into the approved dump yard.
8.1.5.3 Primary Panels
The design length of the primary panels (with two WSI joint formers) is consistent with either the minimum length possible of the size of grab necessary to excavate or full bites at each end of the panel with a small remaining to complete the excavation at the center of the panel.
8.1.5.4 Successive Panels
The panels that are equipped with only one WSI joint former are successive panels.
8.1.5.5 Secondary Panels
The panels that are to be constructed in the last stage upon completion of the previous primary and successive panels. No WSI joint former needs to be installed.
8.1.5.6 Overcoming Obstacles
Dependent on the nature and size of the obstruction, several alternative methods can be adopted for removal of obstacles :-
a) By grabbing where the size of the obstructions is compatible with the size of the grab;
b) By using rock boring tools or down the hole hammer noting that chiseling is not allowed.
Rock boring tools or down the hole hammer shall be utilized to cut the boulder/rock into size that compatible with the jaw of grab before being grab out.
8.1.5.7 Verticality Monitoring
During excavation, the operator can have an easy visual way to monitor possible deviations. The simple watch of the position of the suspension cable of the clamshell in relation to the guide walls is a clear and relatively accurate way to estimate any possible deviation.
8.1.6 Cleaning of Base and Recycling of Bentonite
Upon completion of excavation, the bottom of the trench is thoroughly cleaned with the clamshell prior to recycling of the bentonite. A submersible turbine pump attached to a tremie tube is lowered to the bottom of the panel. The bentonite, loaded with soil particles in suspension, is drawn off from the bottom of the trench and re-cycled through a Caviem or equivalent recycling unit. The process is continued until the bentonite arriving from the trench base satisfies the specification given in Appendix 15.5.
8.1.7 WSI Joint System
“WSI” Joint System in the past decade was developed for allowing the the execution of watertight joints between diaphragm wall panels.
8.1.7.1 WSI Joint principle
The WSI Joint is a stop end extracted sideways when excavating the adjacent panels, thus bringing a positive answer to the problems encountered when extracting sliding forms.
8.1.7.2 Installation
During the recycling of the bentonite after excavation is completed, WSI joints are installed at the end of the excavated panels, primary panels having a joint at both ends and successive panels at one end. The stop ends consist of separate sections bolted together and lowered successively into the trench until the WSI joint reaches the design depth, which is few meters below the future bulk excavation level or into the low permeability soil layer.
The WSI joint is a stop end form extracted laterally. A rubber water stop is incorporated into the joint prior to placing the WSI joint into the diaphragm wall panel. The WSI joint left in place at the end of the panel while the adjacent panel is being excavated. The excavation equipment is then guided by and removes the WSI during excavation of the subsequent panel.
A typical section of the joint is attached.(Appendix 15.6)
8.1.7.3 WSI Joint System and clamshell
Due to their suspension by cables and their rectangular shape, the clamshells are very well suited for use in conjunction with the WSI system. The excavation tool is locked on the WSI at regular intervals throughout the excavation operation, bringing an immediate correction to any tendency to deviate.
8.1.7.4 Advantage in using the WSI Joint
The use of the WSI Joint system brings four main advantages to the construction of better quality diaphragm walls.
8.1.7.5 Stop end removal is totally independent from concrete placement operations, this allows better site efficiency organization and planning. This also alleviates the need for extending working hours beyond the end of the concrete pour.
8.1.7.6 An excellent guide is provided for the excavation of the adjacent panel.
8.1.7.7 It allows the installation of rubber water stop.
8.1.7.8 As the WSI form is left in place at the end of the panel while the next panel is being excavate, it protects the concrete of the previous panel. Therefore the geometry, the cleanliness and the quality of the joint are excellent.
8.1.8 Placing of Reinforcement
Reinforcement cages are pre-fabricated on site and upon completion of recycling the bentonite and installation of WSI joint(s), the cage is lowered into the slurry trench by crawler crane. The cage is equipped with concrete spacer “skids” to ensure that the specified minimum concrete cover to the reinforcement is maintained.
The steel cages are generally composed of 12m long sub-cage elements connected by welding the designed lap length during lowering into the excavation trench. Once all the sub-cages are lowered, they are suspended to the required level from the guide walls by measured suspension bars connected with the calculated lengths in preparation for concreting.
Reservation for box-outs shall be fixed in the sub-cage and positioned by tape measurement from the top fo the corresponding sub-cage.
Where an inclinometer is required in a diaphragm wall panel, reservation in the form of welding connected steel pipe for inclinometer shall be provided into the reinforcement cage. Installation of the inclinometer access tubing can be carried out at a later stage after concreting of the diaphragm wall panel.
8.1.9 Placing of Concrete
Concrete is poured into the trench through tremie pipes. The tremie pipes are 270mm and are made up of coupled sections 0.5m, 1m, 2m, and 3m in length. As the level of concrete in the trench rises, the tremie pipe column is raised whilst always ensuring a minimum 2m embedment into the concrete in order to avoid bentonite inclusions.
During concreting, a log is kept of delivery times, volumes and concrete levels. Concrete cubes are taken to assess the concrete strength.
8.1.10 Diaphragm Wall Equipment
A list of equipment type necessary to carry out the works is given below:-
• Excavation crawler crane : model Liedherr 852 or equivalent;
• Excavating clamshell : in sufficient numbers;
• Bentonite mixing unit : digestor mixer withmission pump 3x4R;
• Bentonite recycling unit “ Caviem 100m2/hr;
• Bentonite storage : 1 to 2 Nos. pools each of about 200m3
• Service crawler cranes : cranes with capacity between 50-100 Tonnes.
• Various pumps and tremie pipes for recycling;
• WSI joints;
• Offices, workshops and changing rooms;
• Mud laboratory
The number of excavation rigs will be adjusted depending on the construction period and the soil condition.
8.1.11 Report Form
Various report forms used for diaphragm walling are enclosed in Appendix 15.7.
8.1.12 Pre-cautions
A number of pre-cautions will be undertaken prior to commencement of work and during the construction of diaphragm wall as follows :-
a. Trench Stability Analysis shall be carried out to determine the following:-
i. Maximum panel length
ii. Minimum bentonite density
iii. Minimum height of bentonite level in trench
b. Ensuring that the bentonite is not below the minimum level as required for stability. As a precaution against the unlikely event of collapse, bentonite level is always maintain at 0.4m below guide walls. As a good practice, the guide walls shall be constructed at least 1m above the ground water table and the bentonite level is kept near to the top of guide walls.
c. Maintaining density of bentonite so that it is above the minimum density required for stability.
d. Handling and treatment of bentonite so that its stabilizing properties is not affected.
e. Detracting of panel sizes so that is does not exceed the maximum panel size for such stability.
f. Stockpile of soil will be maintained on site as a contingent measured in case of backfilling is require due to some reasons.
g. In the event of a collapse, excavated trench will be backfilled with stockpile material until the situation is under control.
h. In the unlikely event of the sudden loss of bentonite slurry, the excavation will be immediately stopped and back-filled with stockpile material until the excavated trench is stable.
i. During desanding of bentonite while the bentonite is pumped from the bottom of trench to the desander, precaution has to be taken to ensure that the supply of treated fo fresh bentonite to the trench is regulated to ensure that the supply of treated or fresh bentonite to the trench is regulated to ensure that the level of bentonite does not fall below the required level for trench stability.
9.0 CONSTRUCTION PHASING AND WORKFLOW
Please refer appendix 15.3
10.0 TRAFFIC MANAGEMENT AND MONITORING
10.1 Maintenance of Existing Roads, Footpaths and Service Drains, Etc.
The construction team shall maintain all existing site access, roads, footpath, service drain, etc. and reinstate any damage caused by any reason whatsoever during the progress of the works.
It will be the Logistic Manager’s responsibility to ensure that ingress and egress to the site are kept free from obstruction brought about by the work on this site and in no way shall cause hindrance to traffic or ancillary works either by his own vehicles or by his work people, material, etc.
11.0 SAFETY PROGRAMME
11.1 Safety Hoarding, Temporary Works and Public Safety
The Logistic Manager shall be responsible for submission of plans and drawings to the relevant Authorities for the construction of all the necessary temporary fencing and protection hoardings, temporary drains and desilting pits, safety nettings, screens, etc. for the works.
The Logistic Manager shall provide adequate signboards at all strategic positions warning the public to keep away from the work site and erect temporary fencing and barriers where necessary around the site to prevent unauthorized trespassing during works.
11.2 Pollution and Disturbance
The HSSE Manager shall be responsible to take necessary measures to ensure that noise and air pollutions are orderly controlled to satisfy the full requirements of the relevant authorities.
He shall also ensure that disturbance due to noise and air pollutions caused by the works to the neighbourhoods and public are kept to an absolute minimum.
In particular, the HSSE Manager shall ensure that the existing driveway areas are constantly wet to prevent excessive dust / air pollution during the demolition work.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.1 for Inspection Test Plan and Appendix 15.2 for the Diaphragm wall checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable.
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan.
15.0 APPENDICES
Appendix 15.1 Inspection Test Plan
Appendix 15.2 Inspection Checklist
Appendix 15.3 Construction Flow (Step 1 to Step 8)
Appendix 15.4 Guide Wall Design Calculations & Typical Details
Appendix 15.5 Bentonite Slurry Testing Frequency
Appendix 15.6 WSI Joint Technical Data
Appendix 15.7 Reporting Form
Appendix 15.8 Job Safety Analysis
DIAPHRAGM WALL
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This submission explains the method of construction to be adopted for the diaphragm walling at the project site.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not applicable.
3.0 CONTRACTING METHOD
The conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-PCSBs. The conditions are bespoke for this project and therefore be required to be reflected in any form of subcontract utilized on this project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHOD
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower / Labour
The number of manpower / labour to be used during the activities have been identified in the Manpower Record (Weekly Progress Report).
5.2 Plant Equipment
~ Excavation Crane Liebherr 853
~ Service Crane Link Belt LS 108-BS Crawler Crane
~ 25T Mobile Crane
~ Miller Welding Machine
~ Hydraulic Excavator
~ 600mm diameter coring tools
~ 600mm Clamshell
~ Chisel TD600
~ Office / store container
~ Generator set 300kVA and 125kVA
~ Tremie pipes c/w Hopper
~ Tremie brake
~ Caviem Desander
~ Desilter
~ Desanding pump
~ 1m3 Digestuer
~ Tsurumi GPN3 Submersible pump
~ Silo
~ Mission pump
~ WSI Joint x 12m length
6.0 LOGISTICS PROVISIONS
The logistic control shall be in accordance with the approved Site Logistic Plan.
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Details of the construction method are considered according to the following matters:
1. Outline Method
2. Guide Wall
3. Bentonite
4. Soil Investigation
5. Diaphragm Wall Excavation
6. Recycling of Bentonite
7. WSI Joints (Construction Joints)
8. Placement of Reinforcement
9. Placing of Concrete
10. Diaphragm Wall Equipment
11. Report Form
12. Precautions
8.1.1 Outline Method
The Diaphragm Wall technique consist of constructing reinforced concrete walls from existing ground level by first excavation a trench by grab. During excavation, the sides of the trench are supported by bentonite slurry.
Upon completion of excavation, a steel reinforcement cage is lowered into the slurry and concrete is then poured into the trench by the tremie method.
As the concrete level rises, excess bentonite is drawn off for re-use. WSI Joints are used to form the joints between adjacent panels.
8.1.2 Guide Wall
In order to guide the grab during initial excavation for each panel and plus ensure the position and verticality of the diaphragm wall, a guide wall is constructed at around 0.5m from ground level prior to commencement of diaphragm walling. The guide wall also provides support during suspension of the reinforcement cage.(Ref. Appendix 15.4)
8.1.3 Bentonite
The bentonite GTC4 is delivered to site in 50kg per bags, which are stored under cover. The bentonite is mixed by high turbulence mixers and the slurry is stored in storage reservoirs until used in the trench.
A laboratory is provided on site for regular testing of the slurry. The minimum frequency of testing and the acceptable range of physical characteristics of the bentonite slurry are given in Appendix 15.5. Laboratory reports are kept during the construction period.
Apparatus available in the site laboratory includes the following:-
1 mud balance (density test)
1 marsh cone (viscosity test)
1 sand screen set (sand content test)
1 shearometer of Fann viscometer (shear strength test)
Paper of measuring pH
Contaminated bentonite slurry will be discarded to an acceptable dump area.
8.1.4 Soil Investigation
Prior to commencement of diaphragm walling, soil investigation holes to assess the geological conditions will be drilled/provided.
From the site investigation information, the excavation techniques are finalized and should obstructions be anticipated, the most appropriate method of treatment is planned.
8.1.5 Diaphragm Wall Excavation
8.1.5.1 General
Excavation utilizes rectangular grabs cable-operated by crane. During the excavation process, the bentonite slurry is kept to within 0.4m of the level of the top of the guide wall. The vertically of the trench is monitored by visual inspection of the crane cables during successive lowering of the grab into the trench.
The excavation crane would be maintained at a minimum distance of 4.5m from the edge of opened trench. Any movement of excavation crane will be supervised by the foreman to enforce this requirement.
Various types of panel are used, primary, successive and secondary (closing) panel.
The general arrangement of panels will be submitted separately later as shopdrawings.
8.1.5.2 Removal of Earth During Excavation
Excavated earth from the trench will be temporary stockpile on the platform and will be removed by using hydraulic excavator load into truck and dump into the approved dump yard.
8.1.5.3 Primary Panels
The design length of the primary panels (with two WSI joint formers) is consistent with either the minimum length possible of the size of grab necessary to excavate or full bites at each end of the panel with a small remaining to complete the excavation at the center of the panel.
8.1.5.4 Successive Panels
The panels that are equipped with only one WSI joint former are successive panels.
8.1.5.5 Secondary Panels
The panels that are to be constructed in the last stage upon completion of the previous primary and successive panels. No WSI joint former needs to be installed.
8.1.5.6 Overcoming Obstacles
Dependent on the nature and size of the obstruction, several alternative methods can be adopted for removal of obstacles :-
a) By grabbing where the size of the obstructions is compatible with the size of the grab;
b) By using rock boring tools or down the hole hammer noting that chiseling is not allowed.
Rock boring tools or down the hole hammer shall be utilized to cut the boulder/rock into size that compatible with the jaw of grab before being grab out.
8.1.5.7 Verticality Monitoring
During excavation, the operator can have an easy visual way to monitor possible deviations. The simple watch of the position of the suspension cable of the clamshell in relation to the guide walls is a clear and relatively accurate way to estimate any possible deviation.
8.1.6 Cleaning of Base and Recycling of Bentonite
Upon completion of excavation, the bottom of the trench is thoroughly cleaned with the clamshell prior to recycling of the bentonite. A submersible turbine pump attached to a tremie tube is lowered to the bottom of the panel. The bentonite, loaded with soil particles in suspension, is drawn off from the bottom of the trench and re-cycled through a Caviem or equivalent recycling unit. The process is continued until the bentonite arriving from the trench base satisfies the specification given in Appendix 15.5.
8.1.7 WSI Joint System
“WSI” Joint System in the past decade was developed for allowing the the execution of watertight joints between diaphragm wall panels.
8.1.7.1 WSI Joint principle
The WSI Joint is a stop end extracted sideways when excavating the adjacent panels, thus bringing a positive answer to the problems encountered when extracting sliding forms.
8.1.7.2 Installation
During the recycling of the bentonite after excavation is completed, WSI joints are installed at the end of the excavated panels, primary panels having a joint at both ends and successive panels at one end. The stop ends consist of separate sections bolted together and lowered successively into the trench until the WSI joint reaches the design depth, which is few meters below the future bulk excavation level or into the low permeability soil layer.
The WSI joint is a stop end form extracted laterally. A rubber water stop is incorporated into the joint prior to placing the WSI joint into the diaphragm wall panel. The WSI joint left in place at the end of the panel while the adjacent panel is being excavated. The excavation equipment is then guided by and removes the WSI during excavation of the subsequent panel.
A typical section of the joint is attached.(Appendix 15.6)
8.1.7.3 WSI Joint System and clamshell
Due to their suspension by cables and their rectangular shape, the clamshells are very well suited for use in conjunction with the WSI system. The excavation tool is locked on the WSI at regular intervals throughout the excavation operation, bringing an immediate correction to any tendency to deviate.
8.1.7.4 Advantage in using the WSI Joint
The use of the WSI Joint system brings four main advantages to the construction of better quality diaphragm walls.
8.1.7.5 Stop end removal is totally independent from concrete placement operations, this allows better site efficiency organization and planning. This also alleviates the need for extending working hours beyond the end of the concrete pour.
8.1.7.6 An excellent guide is provided for the excavation of the adjacent panel.
8.1.7.7 It allows the installation of rubber water stop.
8.1.7.8 As the WSI form is left in place at the end of the panel while the next panel is being excavate, it protects the concrete of the previous panel. Therefore the geometry, the cleanliness and the quality of the joint are excellent.
8.1.8 Placing of Reinforcement
Reinforcement cages are pre-fabricated on site and upon completion of recycling the bentonite and installation of WSI joint(s), the cage is lowered into the slurry trench by crawler crane. The cage is equipped with concrete spacer “skids” to ensure that the specified minimum concrete cover to the reinforcement is maintained.
The steel cages are generally composed of 12m long sub-cage elements connected by welding the designed lap length during lowering into the excavation trench. Once all the sub-cages are lowered, they are suspended to the required level from the guide walls by measured suspension bars connected with the calculated lengths in preparation for concreting.
Reservation for box-outs shall be fixed in the sub-cage and positioned by tape measurement from the top fo the corresponding sub-cage.
Where an inclinometer is required in a diaphragm wall panel, reservation in the form of welding connected steel pipe for inclinometer shall be provided into the reinforcement cage. Installation of the inclinometer access tubing can be carried out at a later stage after concreting of the diaphragm wall panel.
8.1.9 Placing of Concrete
Concrete is poured into the trench through tremie pipes. The tremie pipes are 270mm and are made up of coupled sections 0.5m, 1m, 2m, and 3m in length. As the level of concrete in the trench rises, the tremie pipe column is raised whilst always ensuring a minimum 2m embedment into the concrete in order to avoid bentonite inclusions.
During concreting, a log is kept of delivery times, volumes and concrete levels. Concrete cubes are taken to assess the concrete strength.
8.1.10 Diaphragm Wall Equipment
A list of equipment type necessary to carry out the works is given below:-
• Excavation crawler crane : model Liedherr 852 or equivalent;
• Excavating clamshell : in sufficient numbers;
• Bentonite mixing unit : digestor mixer withmission pump 3x4R;
• Bentonite recycling unit “ Caviem 100m2/hr;
• Bentonite storage : 1 to 2 Nos. pools each of about 200m3
• Service crawler cranes : cranes with capacity between 50-100 Tonnes.
• Various pumps and tremie pipes for recycling;
• WSI joints;
• Offices, workshops and changing rooms;
• Mud laboratory
The number of excavation rigs will be adjusted depending on the construction period and the soil condition.
8.1.11 Report Form
Various report forms used for diaphragm walling are enclosed in Appendix 15.7.
8.1.12 Pre-cautions
A number of pre-cautions will be undertaken prior to commencement of work and during the construction of diaphragm wall as follows :-
a. Trench Stability Analysis shall be carried out to determine the following:-
i. Maximum panel length
ii. Minimum bentonite density
iii. Minimum height of bentonite level in trench
b. Ensuring that the bentonite is not below the minimum level as required for stability. As a precaution against the unlikely event of collapse, bentonite level is always maintain at 0.4m below guide walls. As a good practice, the guide walls shall be constructed at least 1m above the ground water table and the bentonite level is kept near to the top of guide walls.
c. Maintaining density of bentonite so that it is above the minimum density required for stability.
d. Handling and treatment of bentonite so that its stabilizing properties is not affected.
e. Detracting of panel sizes so that is does not exceed the maximum panel size for such stability.
f. Stockpile of soil will be maintained on site as a contingent measured in case of backfilling is require due to some reasons.
g. In the event of a collapse, excavated trench will be backfilled with stockpile material until the situation is under control.
h. In the unlikely event of the sudden loss of bentonite slurry, the excavation will be immediately stopped and back-filled with stockpile material until the excavated trench is stable.
i. During desanding of bentonite while the bentonite is pumped from the bottom of trench to the desander, precaution has to be taken to ensure that the supply of treated fo fresh bentonite to the trench is regulated to ensure that the supply of treated or fresh bentonite to the trench is regulated to ensure that the level of bentonite does not fall below the required level for trench stability.
9.0 CONSTRUCTION PHASING AND WORKFLOW
Please refer appendix 15.3
10.0 TRAFFIC MANAGEMENT AND MONITORING
10.1 Maintenance of Existing Roads, Footpaths and Service Drains, Etc.
The construction team shall maintain all existing site access, roads, footpath, service drain, etc. and reinstate any damage caused by any reason whatsoever during the progress of the works.
It will be the Logistic Manager’s responsibility to ensure that ingress and egress to the site are kept free from obstruction brought about by the work on this site and in no way shall cause hindrance to traffic or ancillary works either by his own vehicles or by his work people, material, etc.
11.0 SAFETY PROGRAMME
11.1 Safety Hoarding, Temporary Works and Public Safety
The Logistic Manager shall be responsible for submission of plans and drawings to the relevant Authorities for the construction of all the necessary temporary fencing and protection hoardings, temporary drains and desilting pits, safety nettings, screens, etc. for the works.
The Logistic Manager shall provide adequate signboards at all strategic positions warning the public to keep away from the work site and erect temporary fencing and barriers where necessary around the site to prevent unauthorized trespassing during works.
11.2 Pollution and Disturbance
The HSSE Manager shall be responsible to take necessary measures to ensure that noise and air pollutions are orderly controlled to satisfy the full requirements of the relevant authorities.
He shall also ensure that disturbance due to noise and air pollutions caused by the works to the neighbourhoods and public are kept to an absolute minimum.
In particular, the HSSE Manager shall ensure that the existing driveway areas are constantly wet to prevent excessive dust / air pollution during the demolition work.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.1 for Inspection Test Plan and Appendix 15.2 for the Diaphragm wall checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable.
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan.
15.0 APPENDICES
Appendix 15.1 Inspection Test Plan
Appendix 15.2 Inspection Checklist
Appendix 15.3 Construction Flow (Step 1 to Step 8)
Appendix 15.4 Guide Wall Design Calculations & Typical Details
Appendix 15.5 Bentonite Slurry Testing Frequency
Appendix 15.6 WSI Joint Technical Data
Appendix 15.7 Reporting Form
Appendix 15.8 Job Safety Analysis
Work method statement for Granite Floor and Wall
WORKS METHOD STATEMENT
FLOOR AND WALL COVERING
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This Work Method Statement is to ensure the floor and wall covering is carried out in a controlled and systematic manner that in all respect confirm to the specification.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not Applicable.
3.0 CONTRACTING METHODS
Since PCSB is liable for the performance of any Sub-contractor, it is vital that only companies with proven track records in the relevant activity will be engaged as Sub -contractors.
It is acknowledged that before any part of the works can be sublet, the approval of the Employer’s Representative is required.
The Conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-contractors. The conditions are bespoke for this project and therefore be required to be reflected in any form of Sub-contract utilized on the project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHODS
Please refer to PHOS-PR-010 to PHOS-PR-030 for the procurement procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower/Labour
The number of manpower/labour to be used during the activities have been identified in the Manpower Histogram.
5.2 Plant Equipment
Typical plant equipment to be used shall consist of:
~ Mechanical mixing
~ Brush
~ Roller or broom
~ Gauging water
~ Dowel pin
6.0 LOGISTICS PROVISIONS
Not Applicable
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Handling Material
1. Temporary Storage Area
• Upon arrival of the crates at the temporary storage area, check the quantity of the crates and the crate number against the purchase order and the delivery order to ensure that the correct quantity and crate number are delivered to site
• Unload the crates to the specific area in the temporary storage area
• The crates shall be stored sector by sector for retrieval when they are required to be transported to the required area
2. Installation Location
• Forklifts are employed to transport the crates to a specific where the crates will be hoisted up to the respective floor where the granite are required for installation
• At the respective floor, the crates will be conveyed to the respective installation location where they are required for installation
• Open the crates and remove the crates for installation
8.2 Installation for Floor Finishes – Semi Dry Method
1. Surface Preparation
• The RC floor slab must be aged for at least 6 weeks (preferably longer) before the cement – sand screed is laid
• The RC surface must be dry, sound and free of contamination for example grease, dust, laitance, oil and etc which might impair adhesion between cement – sand screed and RC floor slab
2. Bonding Agent
• To ensure that cement – sand screed adheres securely onto the RC slab surface, a Bonding Agent is recommended to be applied at the interface of the screed and RC floor slab
• For the purpose, mix 1 part Belle Multi Bond, latex admixture to 1.5 part of Ordinary Portland Cement (OPC) by volume
• Mix until a thin slurry consistency is obtained. Mechanical mixing is recommended. Apply bond agent onto RC surface using brush, roller or broom at thickness not more than 1 mm.
• While the bonding agent is still wet or tacky, the cement sand mortar must be immediately placed over it for best bonding results.
• Where a screed is to be constructed as an unbounded screed at thickness of 50 mm or more, a bonding agent is unnecessary. For screed in excess of 50 mm reinforcement with steel fabric / wire mesh at its mid bed is recommended to prevent curling of the screed.
3. Granite Slab Setting Bed
• For installation of white colour 1200 x 600 x 25 mm granite slabs onto matured cement sand screed at internal floor areas, use Belcem Marblefix White, a white colour, water resistant, ultra thick bed, cement based adhesive complying to BS 5980:1980 (MS 1295:1992) fpor a type 1 class AA adhesive or ANSI A 118.1 :1992
• When fixing dense granite slabs or those treated with a water repellent impregnator, Belcem Marblefex must be incorporated with Belcem Admix plus, a latex admixture in replacement of gauging water
• Apply / spread adhesive onto substrate with a thick bed solid notched trowel at trowelled thickness of approximately 6 – 9 mm.
• For large format granite slabs, a thin coat of adhesive (approximately 3.0 mm) may need to be back buttered to the granite slabs back, before it is bedded onto the spread adhesive bed. This will ensure solid bed fixing granite back in full contact with adhesive bed.
• Press or knock granites firmly onto spread adhesive bed followed by slight sliding action to ensure good contact with adhesive bed, eliminate hollow areas or air voids and to adjust the finish level.
• Apply/spread adhesive to small areas at a time (approximately 1 m2 ) to avoid surface drying (skin over) of the adhesive.
• Allow granite slab installation to set for approx 24 – 48 hours before it is subjected to light footed traffic during grouting
• Mix ratio : 6 – 7 liters Belcem Admix Plus to 20 kg Belcem Granite Fix
• Open time : approximately 15 minutes depending on atmospheric condition
• Pot life : approximately 3 – 4 hours depending on atmospheric condition
8.3 Grouting / Pointing
8.3.1 Internal Dry Areas
• Granite joints should be grouted with Belcem Fine Grout, coloured, water resistant, cement based suitable for joints up to 3 mm wide
• When grouting to internal dry areas, mix grout with clean water only. Mix with a mechanical mixer until a uniform coloured, thin creamy consistency is obtained.
8.3.2 Internal Wet Areas
• Granite joints should be grouted with Belcem Fine Grout, coloured, water resistant, cement based suitable for joints up to 3 mm wide.
• When grouting to internal wet areas, mix grout with Belcem GT Mix I, a latex admixture in replacement of gauging water. Mix with a mechanical mixer until a uniform coloured, thin creamy consistency is obtained.
• Latex modified grout offers greater resistant to penetration of water, improved durability, flexural strength, compressive strength and adhesion to side of granites.
• Allocate joints of approximately 2mm wide between granite slabs.
• Apply grout with a rubber squeegee / float and ensure that joints are fully compacted with grouting material.
• Clean excess grout promptly using a damp cloth or sponge.
• Allow grout to set for at least 24 – 48 hours (preferably longer) before granite slab installation are subjected to normal service condition.
• Mix Ratio – 8 litres Belcem GT-Mix I (Clean water) : 20 kg (1 : 2.5)
8.3.3 Movement Joints
• Movement joints must be incorporated where necessary; complying to the requirements of BS 5385 : Part 1 : 1990 : Clause 20 & BS 5385 : Part 5 : 1990 : Clause 27.
8.4 Installation for Wall Granite – Toppin Bracket System
8.4.1 General Consideration
• Granite panels shall be installed about 100mm clear of wall.
• All fixing accessories such as brackets, extension plate shall be made of aluminium, washer, bolt, nut shall be made of stainless steel grade SUS 304.
• Where C-lipped channels to be used, it shall be hot-dipped galvanized (for sub-framing).
• All SHS shall be of mild steel and hot-dipped galvanized after fabrication.
• All welding works shall be of fillet weld. Welding works done on site will be dressed off welding spatters and coated over with galvanized paint.
8.4.2 Setting Out
• Setting out shall be carried out based on reference points provided by the main contractor.
• From these reference point, the reference level is transferred to the external surface of the column / wall by using a leveling instrument. The level for the fabricated truss shall be measured by using a measuring tape. A string is tied across the two extreme ends of the elevation at the marked level for the first elevation. The level for all intermediate columns / wall marked off the taut string. This is repeated for the other elevations.
• Similarly gridlines are set out based on the control points provided by the main contractor. The gridline is marked off from the control points onto columns/walls. The grid line on the last column/wall shall be tied back to the gridline provided by the main contractor. If the tie back does not tally with the measurement in the drawing the whole sequence is checked and repeated if necessary.
• After all the levels and grid lines have been marked on each column/wall, the position of the brackets including the hole position are marked using different colours, e.g. yellow or black for restrains brackets and red for dead-load brackets.
• Marked fabricated truss/channel position on column/wall.
8.4.3 Installation
• Drill holes into column / wall to accommodate fixing accessories, using :
1. Long SST plates or L brackets are welded on to the galvanized RHS frame exactly marked for the fixing of the granite panel.
2. Position of the Toppin Back Hole Bolts are marked exactly behind the granite panel to match the location of the long SST plates or L brackets welded on the hollow section frame. Using a special machine holes are drilled behind the granite panels at the exact position, approximately 20mm in depth.
3. The back bolt is fixed and tightened with nut and washer with extension plates. This predrill back bolt granite panels will be hoisted to exact locations of the welded L angle or plate.
4. During installation, the adjustable toppin system slot hole will accommodate any adjustment required about 20mm to suit site conditions.
• Using prefabricate truss / C-channel (where the design require sub-framing) – Only when necessary or site condition confirm.
1. Insert anchor bolt into holes drilled in the column / wall / beam / floor.
2. Mount prefabricated truss / vertical C-channel and tighten nut.
3. Check verticality and alignment of truss / channel.
4. Mount bracket / horizontal channel onto predrilled hole in truss/channel by means of bolt and nut with washer. To the predrilled hole in the free length of the bracket is inserted a dowel pin. Align the bracket with the dowel pin, embedded in Tenax glue, in the predrilled holes in the granite slabs.
• Apply approved sealant to the back and sides of the granite. Allow to dry.
• Each piece of stone is supported at the back by four toppin brackets bolted to SST plates or L angle welded to the hollow section frame.
• Ensure that the first (bottom) row of granite is aligned, leveled and properly fixed o the hollow section frame.
• The next row will be installed on top of the first row of slabs.
• Check verticality and alignment of each slab.
• Leave finished work square, regular, true to line, level and plane with a satisfactory at all junctions.
• Tape a sheet of 1000g polystyrene over granite and cover with plywood to a height of 1.2m for protection of the installed granite.
9.0 CONSTRUCTION PHASING AND WORKFLOW
Not Applicable
10.0 TRAFFIC MANAGEMENT AND MONITORING
The Logistic Manager and the traffic management contractor shall be responsible for the management and control of the traffic in and out from the construction site.
11.0 SAFETY PROGRAMME
Please refer to PHOS-HS-010 Health and Safety Plan.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.1 for the Inspection and Test Plan and Appendix 15.2 for the Checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan
15.0 APPENDICES
15.1 Inspection and Test Plan
15.2 Inspection Checklist Form
15.3 Job Safety Analysis
15.4 Detail Drawing
FLOOR AND WALL COVERING
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This Work Method Statement is to ensure the floor and wall covering is carried out in a controlled and systematic manner that in all respect confirm to the specification.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not Applicable.
3.0 CONTRACTING METHODS
Since PCSB is liable for the performance of any Sub-contractor, it is vital that only companies with proven track records in the relevant activity will be engaged as Sub -contractors.
It is acknowledged that before any part of the works can be sublet, the approval of the Employer’s Representative is required.
The Conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-contractors. The conditions are bespoke for this project and therefore be required to be reflected in any form of Sub-contract utilized on the project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHODS
Please refer to PHOS-PR-010 to PHOS-PR-030 for the procurement procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower/Labour
The number of manpower/labour to be used during the activities have been identified in the Manpower Histogram.
5.2 Plant Equipment
Typical plant equipment to be used shall consist of:
~ Mechanical mixing
~ Brush
~ Roller or broom
~ Gauging water
~ Dowel pin
6.0 LOGISTICS PROVISIONS
Not Applicable
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Handling Material
1. Temporary Storage Area
• Upon arrival of the crates at the temporary storage area, check the quantity of the crates and the crate number against the purchase order and the delivery order to ensure that the correct quantity and crate number are delivered to site
• Unload the crates to the specific area in the temporary storage area
• The crates shall be stored sector by sector for retrieval when they are required to be transported to the required area
2. Installation Location
• Forklifts are employed to transport the crates to a specific where the crates will be hoisted up to the respective floor where the granite are required for installation
• At the respective floor, the crates will be conveyed to the respective installation location where they are required for installation
• Open the crates and remove the crates for installation
8.2 Installation for Floor Finishes – Semi Dry Method
1. Surface Preparation
• The RC floor slab must be aged for at least 6 weeks (preferably longer) before the cement – sand screed is laid
• The RC surface must be dry, sound and free of contamination for example grease, dust, laitance, oil and etc which might impair adhesion between cement – sand screed and RC floor slab
2. Bonding Agent
• To ensure that cement – sand screed adheres securely onto the RC slab surface, a Bonding Agent is recommended to be applied at the interface of the screed and RC floor slab
• For the purpose, mix 1 part Belle Multi Bond, latex admixture to 1.5 part of Ordinary Portland Cement (OPC) by volume
• Mix until a thin slurry consistency is obtained. Mechanical mixing is recommended. Apply bond agent onto RC surface using brush, roller or broom at thickness not more than 1 mm.
• While the bonding agent is still wet or tacky, the cement sand mortar must be immediately placed over it for best bonding results.
• Where a screed is to be constructed as an unbounded screed at thickness of 50 mm or more, a bonding agent is unnecessary. For screed in excess of 50 mm reinforcement with steel fabric / wire mesh at its mid bed is recommended to prevent curling of the screed.
3. Granite Slab Setting Bed
• For installation of white colour 1200 x 600 x 25 mm granite slabs onto matured cement sand screed at internal floor areas, use Belcem Marblefix White, a white colour, water resistant, ultra thick bed, cement based adhesive complying to BS 5980:1980 (MS 1295:1992) fpor a type 1 class AA adhesive or ANSI A 118.1 :1992
• When fixing dense granite slabs or those treated with a water repellent impregnator, Belcem Marblefex must be incorporated with Belcem Admix plus, a latex admixture in replacement of gauging water
• Apply / spread adhesive onto substrate with a thick bed solid notched trowel at trowelled thickness of approximately 6 – 9 mm.
• For large format granite slabs, a thin coat of adhesive (approximately 3.0 mm) may need to be back buttered to the granite slabs back, before it is bedded onto the spread adhesive bed. This will ensure solid bed fixing granite back in full contact with adhesive bed.
• Press or knock granites firmly onto spread adhesive bed followed by slight sliding action to ensure good contact with adhesive bed, eliminate hollow areas or air voids and to adjust the finish level.
• Apply/spread adhesive to small areas at a time (approximately 1 m2 ) to avoid surface drying (skin over) of the adhesive.
• Allow granite slab installation to set for approx 24 – 48 hours before it is subjected to light footed traffic during grouting
• Mix ratio : 6 – 7 liters Belcem Admix Plus to 20 kg Belcem Granite Fix
• Open time : approximately 15 minutes depending on atmospheric condition
• Pot life : approximately 3 – 4 hours depending on atmospheric condition
8.3 Grouting / Pointing
8.3.1 Internal Dry Areas
• Granite joints should be grouted with Belcem Fine Grout, coloured, water resistant, cement based suitable for joints up to 3 mm wide
• When grouting to internal dry areas, mix grout with clean water only. Mix with a mechanical mixer until a uniform coloured, thin creamy consistency is obtained.
8.3.2 Internal Wet Areas
• Granite joints should be grouted with Belcem Fine Grout, coloured, water resistant, cement based suitable for joints up to 3 mm wide.
• When grouting to internal wet areas, mix grout with Belcem GT Mix I, a latex admixture in replacement of gauging water. Mix with a mechanical mixer until a uniform coloured, thin creamy consistency is obtained.
• Latex modified grout offers greater resistant to penetration of water, improved durability, flexural strength, compressive strength and adhesion to side of granites.
• Allocate joints of approximately 2mm wide between granite slabs.
• Apply grout with a rubber squeegee / float and ensure that joints are fully compacted with grouting material.
• Clean excess grout promptly using a damp cloth or sponge.
• Allow grout to set for at least 24 – 48 hours (preferably longer) before granite slab installation are subjected to normal service condition.
• Mix Ratio – 8 litres Belcem GT-Mix I (Clean water) : 20 kg (1 : 2.5)
8.3.3 Movement Joints
• Movement joints must be incorporated where necessary; complying to the requirements of BS 5385 : Part 1 : 1990 : Clause 20 & BS 5385 : Part 5 : 1990 : Clause 27.
8.4 Installation for Wall Granite – Toppin Bracket System
8.4.1 General Consideration
• Granite panels shall be installed about 100mm clear of wall.
• All fixing accessories such as brackets, extension plate shall be made of aluminium, washer, bolt, nut shall be made of stainless steel grade SUS 304.
• Where C-lipped channels to be used, it shall be hot-dipped galvanized (for sub-framing).
• All SHS shall be of mild steel and hot-dipped galvanized after fabrication.
• All welding works shall be of fillet weld. Welding works done on site will be dressed off welding spatters and coated over with galvanized paint.
8.4.2 Setting Out
• Setting out shall be carried out based on reference points provided by the main contractor.
• From these reference point, the reference level is transferred to the external surface of the column / wall by using a leveling instrument. The level for the fabricated truss shall be measured by using a measuring tape. A string is tied across the two extreme ends of the elevation at the marked level for the first elevation. The level for all intermediate columns / wall marked off the taut string. This is repeated for the other elevations.
• Similarly gridlines are set out based on the control points provided by the main contractor. The gridline is marked off from the control points onto columns/walls. The grid line on the last column/wall shall be tied back to the gridline provided by the main contractor. If the tie back does not tally with the measurement in the drawing the whole sequence is checked and repeated if necessary.
• After all the levels and grid lines have been marked on each column/wall, the position of the brackets including the hole position are marked using different colours, e.g. yellow or black for restrains brackets and red for dead-load brackets.
• Marked fabricated truss/channel position on column/wall.
8.4.3 Installation
• Drill holes into column / wall to accommodate fixing accessories, using :
1. Long SST plates or L brackets are welded on to the galvanized RHS frame exactly marked for the fixing of the granite panel.
2. Position of the Toppin Back Hole Bolts are marked exactly behind the granite panel to match the location of the long SST plates or L brackets welded on the hollow section frame. Using a special machine holes are drilled behind the granite panels at the exact position, approximately 20mm in depth.
3. The back bolt is fixed and tightened with nut and washer with extension plates. This predrill back bolt granite panels will be hoisted to exact locations of the welded L angle or plate.
4. During installation, the adjustable toppin system slot hole will accommodate any adjustment required about 20mm to suit site conditions.
• Using prefabricate truss / C-channel (where the design require sub-framing) – Only when necessary or site condition confirm.
1. Insert anchor bolt into holes drilled in the column / wall / beam / floor.
2. Mount prefabricated truss / vertical C-channel and tighten nut.
3. Check verticality and alignment of truss / channel.
4. Mount bracket / horizontal channel onto predrilled hole in truss/channel by means of bolt and nut with washer. To the predrilled hole in the free length of the bracket is inserted a dowel pin. Align the bracket with the dowel pin, embedded in Tenax glue, in the predrilled holes in the granite slabs.
• Apply approved sealant to the back and sides of the granite. Allow to dry.
• Each piece of stone is supported at the back by four toppin brackets bolted to SST plates or L angle welded to the hollow section frame.
• Ensure that the first (bottom) row of granite is aligned, leveled and properly fixed o the hollow section frame.
• The next row will be installed on top of the first row of slabs.
• Check verticality and alignment of each slab.
• Leave finished work square, regular, true to line, level and plane with a satisfactory at all junctions.
• Tape a sheet of 1000g polystyrene over granite and cover with plywood to a height of 1.2m for protection of the installed granite.
9.0 CONSTRUCTION PHASING AND WORKFLOW
Not Applicable
10.0 TRAFFIC MANAGEMENT AND MONITORING
The Logistic Manager and the traffic management contractor shall be responsible for the management and control of the traffic in and out from the construction site.
11.0 SAFETY PROGRAMME
Please refer to PHOS-HS-010 Health and Safety Plan.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.1 for the Inspection and Test Plan and Appendix 15.2 for the Checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan
15.0 APPENDICES
15.1 Inspection and Test Plan
15.2 Inspection Checklist Form
15.3 Job Safety Analysis
15.4 Detail Drawing
Work Methos statement for water proofing
WORKS METHOD STATEMENT
WATER PROOFING MEMBRANE AT LEVEL 7 BASED ON SITE CONDITION
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This submission explains the method of construction to be adopted for the installation of water proofing membrane system based on the current site condition at level seven.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not Applicable.
3.0 CONTRACTING METHODS
Since PCSB is liable for the performance of any Sub-contractor, it is vital that only companies with proven track records in the relevant activity will be engaged as Sub -contractors.
It is acknowledged that before any part of the works can be sublet, the approval of the Employer’s Representative is required.
The Conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-contractors. The conditions are bespoke for this project and therefore be required to be reflected in any form of Sub-contract utilized on the project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHODS
Please refer to PHOS-PR-010 to PHOS-PR-030 for the procurement procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower/Labour
The number of manpower/labour to be used during the activities have been identified in the Manpower Histogram.
5.2 Plant Equipment
Typical plant equipment to be used shall consist of:
~ Propane gas torch with related glass cylinder
~ Knife
~ Trowel a rounded tip
~ Protective gloves and googles
6.0 LOGISTICS PROVISIONS
Not applicable
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Work Sequence
The area to install the water proofing membrane will be carried out in three (3) stages:
a) Perimeter of plant room
b) Inside plant room
The installation of the water proofing membrane will be divided into two (2) areas i.e. area A (gridline A to D1) and area B (gridline D1 to H).
c) In between the zone (Main, South and North atrium)
Furthermore the sequence of work to install the water proofing membrane will have to consider the fact that other trades material and equipment had being installed on site. More over there is still outstanding works by other trades still in progress.
8.2 Additional Works To Be Carried Out
8.2.1 Concrete encasement / haunch for all the RWDP.
Due to insufficient clearance between the bottom of pipe and the top of structural concrete slab (refer attached photos). The water proofing membrane will not be able to be lay below the RWDP. Therefore the RWDP need to be encased / haunch with concrete in order for the water proofing membrane to be terminate on top of the concrete encasement / haunch. (Refer to attached shop drawing.)
Since the purpose of the concrete is only to encased / haunch the RWDP (non structural) we proposed to use mass concrete to carry out the works.
8.2.2 Enlargement of plinth (between steel structure column and M&E plinth)
Due to the position of steel structure plinth and M&E plinth (refer to attached photo). It is necessary to enlarge the require plinth in order to ensure the water proofing membrane will be properly terminate on top of the plinth. (Refer to attached shop drawing)
Since the purpose of the concrete is only to enlarge the existing plinth (non structural) we proposed to use mass concrete to carry out the works.
8.2.3 Kerb (Brick) Around All M&E Opening
Besides the risers (mechanical and electrical), which is already being design to be closed with brick wall. Kerb need to be install at all M&E opening that penetrate the level 7 slab i.e.: air-cond duct (refer to attached photo) to ensure the termination of the water proofing membrane will be achieve.
In order to achieve the requirement, we propose to construct the kerb by using brick (150mm x 200mm high) and plaster on both sides.
With the brick install, the water proofing membrane will be terminated on top of the kerb. (Refer to attached shop drawing)
8.2.4 Concrete Surround / Kerb for M&E Equipment Not Sitting On Plinth
1. Switch board. (Refer attached photo)
Kerb, using brick and plaster on both sides (150mm x 200mm high) will be install around this equipment to ensure the termination of the water proofing membrane will be achieve. (Refer attached shop drawing)
2. Silencer. (Refer to attached photo)
Concrete surround (using mass concrete) will be form around the support of the silencer. The size of the concrete surround is to match the water proofing membrane requirement. (Refer attached drawing).
8.3 Protection To The M&E Equipment
Prior to installation of the water proofing membrane all the M&E equipment need to be protect from any foreign material i.e. dust, water etc.
The method of protection to be apply to the equipment will be either
a) Wrap a layer of plastic / canvas sheet around the equipment. (refer attached photo)
b) Fix 3mm plywood around the equipment (switch board). (refer attached photo)
8.4 Conclusion
With regard to the current site condition, all the additional works mentioned above need to be carry out properly prior to the installation of the water proofing membrane. Furthermore, all slab surface preparation (refer document no: PHOS/ARC/---/CTS/KPB/499) also need to be complete prior to the installation of the water proofing membrane.
9.0 CONSTRUCTION PHASING AND WORKFLOW
Not applicable
10.0 TRAFFIC MANAGEMENT AND MONITORING
The Logistic Manager and the traffic management contractor shall be responsible for the management and control of the traffic in and out from the construction site.
11.0 SAFETY PROGRAMME
Please refer to PHOS-HS-010 Health and Safety Plan.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.5 for the Inspection and Test Plan and Appendix 15.3 for the Checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan
15.0 APPENDICES
15.1 Coordination drawing level 7 (Typical details)
15.2 Photos of current site condition and method to protect the M&E Equipment
15.3 Inspection Checklist
15.4 Job Safety Analysis
15.5 Inspection And Test Plan
WATER PROOFING MEMBRANE AT LEVEL 7 BASED ON SITE CONDITION
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This submission explains the method of construction to be adopted for the installation of water proofing membrane system based on the current site condition at level seven.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not Applicable.
3.0 CONTRACTING METHODS
Since PCSB is liable for the performance of any Sub-contractor, it is vital that only companies with proven track records in the relevant activity will be engaged as Sub -contractors.
It is acknowledged that before any part of the works can be sublet, the approval of the Employer’s Representative is required.
The Conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-contractors. The conditions are bespoke for this project and therefore be required to be reflected in any form of Sub-contract utilized on the project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHODS
Please refer to PHOS-PR-010 to PHOS-PR-030 for the procurement procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower/Labour
The number of manpower/labour to be used during the activities have been identified in the Manpower Histogram.
5.2 Plant Equipment
Typical plant equipment to be used shall consist of:
~ Propane gas torch with related glass cylinder
~ Knife
~ Trowel a rounded tip
~ Protective gloves and googles
6.0 LOGISTICS PROVISIONS
Not applicable
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Work Sequence
The area to install the water proofing membrane will be carried out in three (3) stages:
a) Perimeter of plant room
b) Inside plant room
The installation of the water proofing membrane will be divided into two (2) areas i.e. area A (gridline A to D1) and area B (gridline D1 to H).
c) In between the zone (Main, South and North atrium)
Furthermore the sequence of work to install the water proofing membrane will have to consider the fact that other trades material and equipment had being installed on site. More over there is still outstanding works by other trades still in progress.
8.2 Additional Works To Be Carried Out
8.2.1 Concrete encasement / haunch for all the RWDP.
Due to insufficient clearance between the bottom of pipe and the top of structural concrete slab (refer attached photos). The water proofing membrane will not be able to be lay below the RWDP. Therefore the RWDP need to be encased / haunch with concrete in order for the water proofing membrane to be terminate on top of the concrete encasement / haunch. (Refer to attached shop drawing.)
Since the purpose of the concrete is only to encased / haunch the RWDP (non structural) we proposed to use mass concrete to carry out the works.
8.2.2 Enlargement of plinth (between steel structure column and M&E plinth)
Due to the position of steel structure plinth and M&E plinth (refer to attached photo). It is necessary to enlarge the require plinth in order to ensure the water proofing membrane will be properly terminate on top of the plinth. (Refer to attached shop drawing)
Since the purpose of the concrete is only to enlarge the existing plinth (non structural) we proposed to use mass concrete to carry out the works.
8.2.3 Kerb (Brick) Around All M&E Opening
Besides the risers (mechanical and electrical), which is already being design to be closed with brick wall. Kerb need to be install at all M&E opening that penetrate the level 7 slab i.e.: air-cond duct (refer to attached photo) to ensure the termination of the water proofing membrane will be achieve.
In order to achieve the requirement, we propose to construct the kerb by using brick (150mm x 200mm high) and plaster on both sides.
With the brick install, the water proofing membrane will be terminated on top of the kerb. (Refer to attached shop drawing)
8.2.4 Concrete Surround / Kerb for M&E Equipment Not Sitting On Plinth
1. Switch board. (Refer attached photo)
Kerb, using brick and plaster on both sides (150mm x 200mm high) will be install around this equipment to ensure the termination of the water proofing membrane will be achieve. (Refer attached shop drawing)
2. Silencer. (Refer to attached photo)
Concrete surround (using mass concrete) will be form around the support of the silencer. The size of the concrete surround is to match the water proofing membrane requirement. (Refer attached drawing).
8.3 Protection To The M&E Equipment
Prior to installation of the water proofing membrane all the M&E equipment need to be protect from any foreign material i.e. dust, water etc.
The method of protection to be apply to the equipment will be either
a) Wrap a layer of plastic / canvas sheet around the equipment. (refer attached photo)
b) Fix 3mm plywood around the equipment (switch board). (refer attached photo)
8.4 Conclusion
With regard to the current site condition, all the additional works mentioned above need to be carry out properly prior to the installation of the water proofing membrane. Furthermore, all slab surface preparation (refer document no: PHOS/ARC/---/CTS/KPB/499) also need to be complete prior to the installation of the water proofing membrane.
9.0 CONSTRUCTION PHASING AND WORKFLOW
Not applicable
10.0 TRAFFIC MANAGEMENT AND MONITORING
The Logistic Manager and the traffic management contractor shall be responsible for the management and control of the traffic in and out from the construction site.
11.0 SAFETY PROGRAMME
Please refer to PHOS-HS-010 Health and Safety Plan.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.5 for the Inspection and Test Plan and Appendix 15.3 for the Checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan
15.0 APPENDICES
15.1 Coordination drawing level 7 (Typical details)
15.2 Photos of current site condition and method to protect the M&E Equipment
15.3 Inspection Checklist
15.4 Job Safety Analysis
15.5 Inspection And Test Plan
Work Method Statement for Diapharm Wall
WORKS METHOD STATEMENT
DIAPHRAGM WALL
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This submission explains the method of construction to be adopted for the diaphragm walling at the project site.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not applicable.
3.0 CONTRACTING METHOD
The conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-PCSBs. The conditions are bespoke for this project and therefore be required to be reflected in any form of subcontract utilized on this project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHOD
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower / Labour
The number of manpower / labour to be used during the activities have been identified in the Manpower Record (Weekly Progress Report).
5.2 Plant Equipment
~ Excavation Crane Liebherr 853
~ Service Crane Link Belt LS 108-BS Crawler Crane
~ 25T Mobile Crane
~ Miller Welding Machine
~ Hydraulic Excavator
~ 600mm diameter coring tools
~ 600mm Clamshell
~ Chisel TD600
~ Office / store container
~ Generator set 300kVA and 125kVA
~ Tremie pipes c/w Hopper
~ Tremie brake
~ Caviem Desander
~ Desilter
~ Desanding pump
~ 1m3 Digestuer
~ Tsurumi GPN3 Submersible pump
~ Silo
~ Mission pump
~ WSI Joint x 12m length
6.0 LOGISTICS PROVISIONS
The logistic control shall be in accordance with the approved Site Logistic Plan.
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Details of the construction method are considered according to the following matters:
1. Outline Method
2. Guide Wall
3. Bentonite
4. Soil Investigation
5. Diaphragm Wall Excavation
6. Recycling of Bentonite
7. WSI Joints (Construction Joints)
8. Placement of Reinforcement
9. Placing of Concrete
10. Diaphragm Wall Equipment
11. Report Form
12. Precautions
8.1.1 Outline Method
The Diaphragm Wall technique consist of constructing reinforced concrete walls from existing ground level by first excavation a trench by grab. During excavation, the sides of the trench are supported by bentonite slurry.
Upon completion of excavation, a steel reinforcement cage is lowered into the slurry and concrete is then poured into the trench by the tremie method.
As the concrete level rises, excess bentonite is drawn off for re-use. WSI Joints are used to form the joints between adjacent panels.
8.1.2 Guide Wall
In order to guide the grab during initial excavation for each panel and plus ensure the position and verticality of the diaphragm wall, a guide wall is constructed at around 0.5m from ground level prior to commencement of diaphragm walling. The guide wall also provides support during suspension of the reinforcement cage.(Ref. Appendix 15.4)
8.1.3 Bentonite
The bentonite GTC4 is delivered to site in 50kg per bags, which are stored under cover. The bentonite is mixed by high turbulence mixers and the slurry is stored in storage reservoirs until used in the trench.
A laboratory is provided on site for regular testing of the slurry. The minimum frequency of testing and the acceptable range of physical characteristics of the bentonite slurry are given in Appendix 15.5. Laboratory reports are kept during the construction period.
Apparatus available in the site laboratory includes the following:-
1 mud balance (density test)
1 marsh cone (viscosity test)
1 sand screen set (sand content test)
1 shearometer of Fann viscometer (shear strength test)
Paper of measuring pH
Contaminated bentonite slurry will be discarded to an acceptable dump area.
8.1.4 Soil Investigation
Prior to commencement of diaphragm walling, soil investigation holes to assess the geological conditions will be drilled/provided.
From the site investigation information, the excavation techniques are finalized and should obstructions be anticipated, the most appropriate method of treatment is planned.
8.1.5 Diaphragm Wall Excavation
8.1.5.1 General
Excavation utilizes rectangular grabs cable-operated by crane. During the excavation process, the bentonite slurry is kept to within 0.4m of the level of the top of the guide wall. The vertically of the trench is monitored by visual inspection of the crane cables during successive lowering of the grab into the trench.
The excavation crane would be maintained at a minimum distance of 4.5m from the edge of opened trench. Any movement of excavation crane will be supervised by the foreman to enforce this requirement.
Various types of panel are used, primary, successive and secondary (closing) panel.
The general arrangement of panels will be submitted separately later as shopdrawings.
8.1.5.2 Removal of Earth During Excavation
Excavated earth from the trench will be temporary stockpile on the platform and will be removed by using hydraulic excavator load into truck and dump into the approved dump yard.
8.1.5.3 Primary Panels
The design length of the primary panels (with two WSI joint formers) is consistent with either the minimum length possible of the size of grab necessary to excavate or full bites at each end of the panel with a small remaining to complete the excavation at the center of the panel.
8.1.5.4 Successive Panels
The panels that are equipped with only one WSI joint former are successive panels.
8.1.5.5 Secondary Panels
The panels that are to be constructed in the last stage upon completion of the previous primary and successive panels. No WSI joint former needs to be installed.
8.1.5.6 Overcoming Obstacles
Dependent on the nature and size of the obstruction, several alternative methods can be adopted for removal of obstacles :-
a) By grabbing where the size of the obstructions is compatible with the size of the grab;
b) By using rock boring tools or down the hole hammer noting that chiseling is not allowed.
Rock boring tools or down the hole hammer shall be utilized to cut the boulder/rock into size that compatible with the jaw of grab before being grab out.
8.1.5.7 Verticality Monitoring
During excavation, the operator can have an easy visual way to monitor possible deviations. The simple watch of the position of the suspension cable of the clamshell in relation to the guide walls is a clear and relatively accurate way to estimate any possible deviation.
8.1.6 Cleaning of Base and Recycling of Bentonite
Upon completion of excavation, the bottom of the trench is thoroughly cleaned with the clamshell prior to recycling of the bentonite. A submersible turbine pump attached to a tremie tube is lowered to the bottom of the panel. The bentonite, loaded with soil particles in suspension, is drawn off from the bottom of the trench and re-cycled through a Caviem or equivalent recycling unit. The process is continued until the bentonite arriving from the trench base satisfies the specification given in Appendix 15.5.
8.1.7 WSI Joint System
“WSI” Joint System in the past decade was developed for allowing the the execution of watertight joints between diaphragm wall panels.
8.1.7.1 WSI Joint principle
The WSI Joint is a stop end extracted sideways when excavating the adjacent panels, thus bringing a positive answer to the problems encountered when extracting sliding forms.
8.1.7.2 Installation
During the recycling of the bentonite after excavation is completed, WSI joints are installed at the end of the excavated panels, primary panels having a joint at both ends and successive panels at one end. The stop ends consist of separate sections bolted together and lowered successively into the trench until the WSI joint reaches the design depth, which is few meters below the future bulk excavation level or into the low permeability soil layer.
The WSI joint is a stop end form extracted laterally. A rubber water stop is incorporated into the joint prior to placing the WSI joint into the diaphragm wall panel. The WSI joint left in place at the end of the panel while the adjacent panel is being excavated. The excavation equipment is then guided by and removes the WSI during excavation of the subsequent panel.
A typical section of the joint is attached.(Appendix 15.6)
8.1.7.3 WSI Joint System and clamshell
Due to their suspension by cables and their rectangular shape, the clamshells are very well suited for use in conjunction with the WSI system. The excavation tool is locked on the WSI at regular intervals throughout the excavation operation, bringing an immediate correction to any tendency to deviate.
8.1.7.4 Advantage in using the WSI Joint
The use of the WSI Joint system brings four main advantages to the construction of better quality diaphragm walls.
8.1.7.5 Stop end removal is totally independent from concrete placement operations, this allows better site efficiency organization and planning. This also alleviates the need for extending working hours beyond the end of the concrete pour.
8.1.7.6 An excellent guide is provided for the excavation of the adjacent panel.
8.1.7.7 It allows the installation of rubber water stop.
8.1.7.8 As the WSI form is left in place at the end of the panel while the next panel is being excavate, it protects the concrete of the previous panel. Therefore the geometry, the cleanliness and the quality of the joint are excellent.
8.1.8 Placing of Reinforcement
Reinforcement cages are pre-fabricated on site and upon completion of recycling the bentonite and installation of WSI joint(s), the cage is lowered into the slurry trench by crawler crane. The cage is equipped with concrete spacer “skids” to ensure that the specified minimum concrete cover to the reinforcement is maintained.
The steel cages are generally composed of 12m long sub-cage elements connected by welding the designed lap length during lowering into the excavation trench. Once all the sub-cages are lowered, they are suspended to the required level from the guide walls by measured suspension bars connected with the calculated lengths in preparation for concreting.
Reservation for box-outs shall be fixed in the sub-cage and positioned by tape measurement from the top fo the corresponding sub-cage.
Where an inclinometer is required in a diaphragm wall panel, reservation in the form of welding connected steel pipe for inclinometer shall be provided into the reinforcement cage. Installation of the inclinometer access tubing can be carried out at a later stage after concreting of the diaphragm wall panel.
8.1.9 Placing of Concrete
Concrete is poured into the trench through tremie pipes. The tremie pipes are 270mm and are made up of coupled sections 0.5m, 1m, 2m, and 3m in length. As the level of concrete in the trench rises, the tremie pipe column is raised whilst always ensuring a minimum 2m embedment into the concrete in order to avoid bentonite inclusions.
During concreting, a log is kept of delivery times, volumes and concrete levels. Concrete cubes are taken to assess the concrete strength.
8.1.10 Diaphragm Wall Equipment
A list of equipment type necessary to carry out the works is given below:-
• Excavation crawler crane : model Liedherr 852 or equivalent;
• Excavating clamshell : in sufficient numbers;
• Bentonite mixing unit : digestor mixer withmission pump 3x4R;
• Bentonite recycling unit “ Caviem 100m2/hr;
• Bentonite storage : 1 to 2 Nos. pools each of about 200m3
• Service crawler cranes : cranes with capacity between 50-100 Tonnes.
• Various pumps and tremie pipes for recycling;
• WSI joints;
• Offices, workshops and changing rooms;
• Mud laboratory
The number of excavation rigs will be adjusted depending on the construction period and the soil condition.
8.1.11 Report Form
Various report forms used for diaphragm walling are enclosed in Appendix 15.7.
8.1.12 Pre-cautions
A number of pre-cautions will be undertaken prior to commencement of work and during the construction of diaphragm wall as follows :-
a. Trench Stability Analysis shall be carried out to determine the following:-
i. Maximum panel length
ii. Minimum bentonite density
iii. Minimum height of bentonite level in trench
b. Ensuring that the bentonite is not below the minimum level as required for stability. As a precaution against the unlikely event of collapse, bentonite level is always maintain at 0.4m below guide walls. As a good practice, the guide walls shall be constructed at least 1m above the ground water table and the bentonite level is kept near to the top of guide walls.
c. Maintaining density of bentonite so that it is above the minimum density required for stability.
d. Handling and treatment of bentonite so that its stabilizing properties is not affected.
e. Detracting of panel sizes so that is does not exceed the maximum panel size for such stability.
f. Stockpile of soil will be maintained on site as a contingent measured in case of backfilling is require due to some reasons.
g. In the event of a collapse, excavated trench will be backfilled with stockpile material until the situation is under control.
h. In the unlikely event of the sudden loss of bentonite slurry, the excavation will be immediately stopped and back-filled with stockpile material until the excavated trench is stable.
i. During desanding of bentonite while the bentonite is pumped from the bottom of trench to the desander, precaution has to be taken to ensure that the supply of treated fo fresh bentonite to the trench is regulated to ensure that the supply of treated or fresh bentonite to the trench is regulated to ensure that the level of bentonite does not fall below the required level for trench stability.
9.0 CONSTRUCTION PHASING AND WORKFLOW
Please refer appendix 15.3
10.0 TRAFFIC MANAGEMENT AND MONITORING
10.1 Maintenance of Existing Roads, Footpaths and Service Drains, Etc.
The construction team shall maintain all existing site access, roads, footpath, service drain, etc. and reinstate any damage caused by any reason whatsoever during the progress of the works.
It will be the Logistic Manager’s responsibility to ensure that ingress and egress to the site are kept free from obstruction brought about by the work on this site and in no way shall cause hindrance to traffic or ancillary works either by his own vehicles or by his work people, material, etc.
11.0 SAFETY PROGRAMME
11.1 Safety Hoarding, Temporary Works and Public Safety
The Logistic Manager shall be responsible for submission of plans and drawings to the relevant Authorities for the construction of all the necessary temporary fencing and protection hoardings, temporary drains and desilting pits, safety nettings, screens, etc. for the works.
The Logistic Manager shall provide adequate signboards at all strategic positions warning the public to keep away from the work site and erect temporary fencing and barriers where necessary around the site to prevent unauthorized trespassing during works.
11.2 Pollution and Disturbance
The HSSE Manager shall be responsible to take necessary measures to ensure that noise and air pollutions are orderly controlled to satisfy the full requirements of the relevant authorities.
He shall also ensure that disturbance due to noise and air pollutions caused by the works to the neighbourhoods and public are kept to an absolute minimum.
In particular, the HSSE Manager shall ensure that the existing driveway areas are constantly wet to prevent excessive dust / air pollution during the demolition work.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.1 for Inspection Test Plan and Appendix 15.2 for the Diaphragm wall checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable.
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan.
15.0 APPENDICES
Appendix 15.1 Inspection Test Plan
Appendix 15.2 Inspection Checklist
Appendix 15.3 Construction Flow (Step 1 to Step 8)
Appendix 15.4 Guide Wall Design Calculations & Typical Details
Appendix 15.5 Bentonite Slurry Testing Frequency
Appendix 15.6 WSI Joint Technical Data
Appendix 15.7 Reporting Form
Appendix 15.8 Job Safety Analysis
DIAPHRAGM WALL
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This submission explains the method of construction to be adopted for the diaphragm walling at the project site.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not applicable.
3.0 CONTRACTING METHOD
The conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-PCSBs. The conditions are bespoke for this project and therefore be required to be reflected in any form of subcontract utilized on this project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHOD
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower / Labour
The number of manpower / labour to be used during the activities have been identified in the Manpower Record (Weekly Progress Report).
5.2 Plant Equipment
~ Excavation Crane Liebherr 853
~ Service Crane Link Belt LS 108-BS Crawler Crane
~ 25T Mobile Crane
~ Miller Welding Machine
~ Hydraulic Excavator
~ 600mm diameter coring tools
~ 600mm Clamshell
~ Chisel TD600
~ Office / store container
~ Generator set 300kVA and 125kVA
~ Tremie pipes c/w Hopper
~ Tremie brake
~ Caviem Desander
~ Desilter
~ Desanding pump
~ 1m3 Digestuer
~ Tsurumi GPN3 Submersible pump
~ Silo
~ Mission pump
~ WSI Joint x 12m length
6.0 LOGISTICS PROVISIONS
The logistic control shall be in accordance with the approved Site Logistic Plan.
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Details of the construction method are considered according to the following matters:
1. Outline Method
2. Guide Wall
3. Bentonite
4. Soil Investigation
5. Diaphragm Wall Excavation
6. Recycling of Bentonite
7. WSI Joints (Construction Joints)
8. Placement of Reinforcement
9. Placing of Concrete
10. Diaphragm Wall Equipment
11. Report Form
12. Precautions
8.1.1 Outline Method
The Diaphragm Wall technique consist of constructing reinforced concrete walls from existing ground level by first excavation a trench by grab. During excavation, the sides of the trench are supported by bentonite slurry.
Upon completion of excavation, a steel reinforcement cage is lowered into the slurry and concrete is then poured into the trench by the tremie method.
As the concrete level rises, excess bentonite is drawn off for re-use. WSI Joints are used to form the joints between adjacent panels.
8.1.2 Guide Wall
In order to guide the grab during initial excavation for each panel and plus ensure the position and verticality of the diaphragm wall, a guide wall is constructed at around 0.5m from ground level prior to commencement of diaphragm walling. The guide wall also provides support during suspension of the reinforcement cage.(Ref. Appendix 15.4)
8.1.3 Bentonite
The bentonite GTC4 is delivered to site in 50kg per bags, which are stored under cover. The bentonite is mixed by high turbulence mixers and the slurry is stored in storage reservoirs until used in the trench.
A laboratory is provided on site for regular testing of the slurry. The minimum frequency of testing and the acceptable range of physical characteristics of the bentonite slurry are given in Appendix 15.5. Laboratory reports are kept during the construction period.
Apparatus available in the site laboratory includes the following:-
1 mud balance (density test)
1 marsh cone (viscosity test)
1 sand screen set (sand content test)
1 shearometer of Fann viscometer (shear strength test)
Paper of measuring pH
Contaminated bentonite slurry will be discarded to an acceptable dump area.
8.1.4 Soil Investigation
Prior to commencement of diaphragm walling, soil investigation holes to assess the geological conditions will be drilled/provided.
From the site investigation information, the excavation techniques are finalized and should obstructions be anticipated, the most appropriate method of treatment is planned.
8.1.5 Diaphragm Wall Excavation
8.1.5.1 General
Excavation utilizes rectangular grabs cable-operated by crane. During the excavation process, the bentonite slurry is kept to within 0.4m of the level of the top of the guide wall. The vertically of the trench is monitored by visual inspection of the crane cables during successive lowering of the grab into the trench.
The excavation crane would be maintained at a minimum distance of 4.5m from the edge of opened trench. Any movement of excavation crane will be supervised by the foreman to enforce this requirement.
Various types of panel are used, primary, successive and secondary (closing) panel.
The general arrangement of panels will be submitted separately later as shopdrawings.
8.1.5.2 Removal of Earth During Excavation
Excavated earth from the trench will be temporary stockpile on the platform and will be removed by using hydraulic excavator load into truck and dump into the approved dump yard.
8.1.5.3 Primary Panels
The design length of the primary panels (with two WSI joint formers) is consistent with either the minimum length possible of the size of grab necessary to excavate or full bites at each end of the panel with a small remaining to complete the excavation at the center of the panel.
8.1.5.4 Successive Panels
The panels that are equipped with only one WSI joint former are successive panels.
8.1.5.5 Secondary Panels
The panels that are to be constructed in the last stage upon completion of the previous primary and successive panels. No WSI joint former needs to be installed.
8.1.5.6 Overcoming Obstacles
Dependent on the nature and size of the obstruction, several alternative methods can be adopted for removal of obstacles :-
a) By grabbing where the size of the obstructions is compatible with the size of the grab;
b) By using rock boring tools or down the hole hammer noting that chiseling is not allowed.
Rock boring tools or down the hole hammer shall be utilized to cut the boulder/rock into size that compatible with the jaw of grab before being grab out.
8.1.5.7 Verticality Monitoring
During excavation, the operator can have an easy visual way to monitor possible deviations. The simple watch of the position of the suspension cable of the clamshell in relation to the guide walls is a clear and relatively accurate way to estimate any possible deviation.
8.1.6 Cleaning of Base and Recycling of Bentonite
Upon completion of excavation, the bottom of the trench is thoroughly cleaned with the clamshell prior to recycling of the bentonite. A submersible turbine pump attached to a tremie tube is lowered to the bottom of the panel. The bentonite, loaded with soil particles in suspension, is drawn off from the bottom of the trench and re-cycled through a Caviem or equivalent recycling unit. The process is continued until the bentonite arriving from the trench base satisfies the specification given in Appendix 15.5.
8.1.7 WSI Joint System
“WSI” Joint System in the past decade was developed for allowing the the execution of watertight joints between diaphragm wall panels.
8.1.7.1 WSI Joint principle
The WSI Joint is a stop end extracted sideways when excavating the adjacent panels, thus bringing a positive answer to the problems encountered when extracting sliding forms.
8.1.7.2 Installation
During the recycling of the bentonite after excavation is completed, WSI joints are installed at the end of the excavated panels, primary panels having a joint at both ends and successive panels at one end. The stop ends consist of separate sections bolted together and lowered successively into the trench until the WSI joint reaches the design depth, which is few meters below the future bulk excavation level or into the low permeability soil layer.
The WSI joint is a stop end form extracted laterally. A rubber water stop is incorporated into the joint prior to placing the WSI joint into the diaphragm wall panel. The WSI joint left in place at the end of the panel while the adjacent panel is being excavated. The excavation equipment is then guided by and removes the WSI during excavation of the subsequent panel.
A typical section of the joint is attached.(Appendix 15.6)
8.1.7.3 WSI Joint System and clamshell
Due to their suspension by cables and their rectangular shape, the clamshells are very well suited for use in conjunction with the WSI system. The excavation tool is locked on the WSI at regular intervals throughout the excavation operation, bringing an immediate correction to any tendency to deviate.
8.1.7.4 Advantage in using the WSI Joint
The use of the WSI Joint system brings four main advantages to the construction of better quality diaphragm walls.
8.1.7.5 Stop end removal is totally independent from concrete placement operations, this allows better site efficiency organization and planning. This also alleviates the need for extending working hours beyond the end of the concrete pour.
8.1.7.6 An excellent guide is provided for the excavation of the adjacent panel.
8.1.7.7 It allows the installation of rubber water stop.
8.1.7.8 As the WSI form is left in place at the end of the panel while the next panel is being excavate, it protects the concrete of the previous panel. Therefore the geometry, the cleanliness and the quality of the joint are excellent.
8.1.8 Placing of Reinforcement
Reinforcement cages are pre-fabricated on site and upon completion of recycling the bentonite and installation of WSI joint(s), the cage is lowered into the slurry trench by crawler crane. The cage is equipped with concrete spacer “skids” to ensure that the specified minimum concrete cover to the reinforcement is maintained.
The steel cages are generally composed of 12m long sub-cage elements connected by welding the designed lap length during lowering into the excavation trench. Once all the sub-cages are lowered, they are suspended to the required level from the guide walls by measured suspension bars connected with the calculated lengths in preparation for concreting.
Reservation for box-outs shall be fixed in the sub-cage and positioned by tape measurement from the top fo the corresponding sub-cage.
Where an inclinometer is required in a diaphragm wall panel, reservation in the form of welding connected steel pipe for inclinometer shall be provided into the reinforcement cage. Installation of the inclinometer access tubing can be carried out at a later stage after concreting of the diaphragm wall panel.
8.1.9 Placing of Concrete
Concrete is poured into the trench through tremie pipes. The tremie pipes are 270mm and are made up of coupled sections 0.5m, 1m, 2m, and 3m in length. As the level of concrete in the trench rises, the tremie pipe column is raised whilst always ensuring a minimum 2m embedment into the concrete in order to avoid bentonite inclusions.
During concreting, a log is kept of delivery times, volumes and concrete levels. Concrete cubes are taken to assess the concrete strength.
8.1.10 Diaphragm Wall Equipment
A list of equipment type necessary to carry out the works is given below:-
• Excavation crawler crane : model Liedherr 852 or equivalent;
• Excavating clamshell : in sufficient numbers;
• Bentonite mixing unit : digestor mixer withmission pump 3x4R;
• Bentonite recycling unit “ Caviem 100m2/hr;
• Bentonite storage : 1 to 2 Nos. pools each of about 200m3
• Service crawler cranes : cranes with capacity between 50-100 Tonnes.
• Various pumps and tremie pipes for recycling;
• WSI joints;
• Offices, workshops and changing rooms;
• Mud laboratory
The number of excavation rigs will be adjusted depending on the construction period and the soil condition.
8.1.11 Report Form
Various report forms used for diaphragm walling are enclosed in Appendix 15.7.
8.1.12 Pre-cautions
A number of pre-cautions will be undertaken prior to commencement of work and during the construction of diaphragm wall as follows :-
a. Trench Stability Analysis shall be carried out to determine the following:-
i. Maximum panel length
ii. Minimum bentonite density
iii. Minimum height of bentonite level in trench
b. Ensuring that the bentonite is not below the minimum level as required for stability. As a precaution against the unlikely event of collapse, bentonite level is always maintain at 0.4m below guide walls. As a good practice, the guide walls shall be constructed at least 1m above the ground water table and the bentonite level is kept near to the top of guide walls.
c. Maintaining density of bentonite so that it is above the minimum density required for stability.
d. Handling and treatment of bentonite so that its stabilizing properties is not affected.
e. Detracting of panel sizes so that is does not exceed the maximum panel size for such stability.
f. Stockpile of soil will be maintained on site as a contingent measured in case of backfilling is require due to some reasons.
g. In the event of a collapse, excavated trench will be backfilled with stockpile material until the situation is under control.
h. In the unlikely event of the sudden loss of bentonite slurry, the excavation will be immediately stopped and back-filled with stockpile material until the excavated trench is stable.
i. During desanding of bentonite while the bentonite is pumped from the bottom of trench to the desander, precaution has to be taken to ensure that the supply of treated fo fresh bentonite to the trench is regulated to ensure that the supply of treated or fresh bentonite to the trench is regulated to ensure that the level of bentonite does not fall below the required level for trench stability.
9.0 CONSTRUCTION PHASING AND WORKFLOW
Please refer appendix 15.3
10.0 TRAFFIC MANAGEMENT AND MONITORING
10.1 Maintenance of Existing Roads, Footpaths and Service Drains, Etc.
The construction team shall maintain all existing site access, roads, footpath, service drain, etc. and reinstate any damage caused by any reason whatsoever during the progress of the works.
It will be the Logistic Manager’s responsibility to ensure that ingress and egress to the site are kept free from obstruction brought about by the work on this site and in no way shall cause hindrance to traffic or ancillary works either by his own vehicles or by his work people, material, etc.
11.0 SAFETY PROGRAMME
11.1 Safety Hoarding, Temporary Works and Public Safety
The Logistic Manager shall be responsible for submission of plans and drawings to the relevant Authorities for the construction of all the necessary temporary fencing and protection hoardings, temporary drains and desilting pits, safety nettings, screens, etc. for the works.
The Logistic Manager shall provide adequate signboards at all strategic positions warning the public to keep away from the work site and erect temporary fencing and barriers where necessary around the site to prevent unauthorized trespassing during works.
11.2 Pollution and Disturbance
The HSSE Manager shall be responsible to take necessary measures to ensure that noise and air pollutions are orderly controlled to satisfy the full requirements of the relevant authorities.
He shall also ensure that disturbance due to noise and air pollutions caused by the works to the neighbourhoods and public are kept to an absolute minimum.
In particular, the HSSE Manager shall ensure that the existing driveway areas are constantly wet to prevent excessive dust / air pollution during the demolition work.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.1 for Inspection Test Plan and Appendix 15.2 for the Diaphragm wall checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable.
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan.
15.0 APPENDICES
Appendix 15.1 Inspection Test Plan
Appendix 15.2 Inspection Checklist
Appendix 15.3 Construction Flow (Step 1 to Step 8)
Appendix 15.4 Guide Wall Design Calculations & Typical Details
Appendix 15.5 Bentonite Slurry Testing Frequency
Appendix 15.6 WSI Joint Technical Data
Appendix 15.7 Reporting Form
Appendix 15.8 Job Safety Analysis
Work Method Statement for Ceramic Wall Tile
WORKS METHOD STATEMENT
CERAMIC/HOMOGENEOUS TILING
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This Work Method Statement is to describe the materials and procedures for the installation of tiling works This method statement also describes the technical method of application and the sequence of works to be carried out for Private Hospital Project at Jalan Tun Razak.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not Applicable.
3.0 CONTRACTING METHODS
Since PCSB is liable for the performance of any Sub-contractor, it is vital that only companies with proven track records in the relevant activity will be engaged as Sub -contractors.
It is acknowledged that before any part of the works can be sublet, the approval of the Employer’s Representative is required.
The Conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-contractors. The conditions are bespoke for this project and therefore be required to be reflected in any form of Sub-contract utilized on the project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHODS
Please refer to PHOS-PR-010 to PHOS-PR-030 for the procurement procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower/Labour
The number of manpower/labour to be used during the earthworks activities have been identified in the Manpower Histogram.
5.2 Plant Equipment
Typical plant equipment to be used shall consist of:
~ Grease
~ Duct Tape
~ Levelling spirit
~ Welded holding down bolt template
~ 45 T mobile crane
6.0 LOGISTICS PROVISIONS
The logistic control shall be in accordance with the approved Site Logistic Plan and includes wheel wash facilities and traffic management.
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Surface Preparation
• To check and survey site, layout marking and setting.
• Screed shall be laid after concrete slab has been thoroughly roughened, cleaned, wetted and spread with a layer of neat cement slurry. Screed shall be 1:3 cement and sand mixture. The setting bed for floor tile shall be of neat cement grout of the right consistency.
• Edge restraint is normally necessary, it serve to restraint lateral movement of the tiles. All cutting of tiles by high – speed cutter is to be neatly carried out and suit site formation/edge.
8.2 Floor Tile Installation
• Unload of tiles by mechanical means and stored. Each tile shall be loaded into trolley and transported to area to be laid.
• To unload place and lay tiles by hand into position over neatly cement screed
• A control joint shall be established with regard to structure location and tiles are not to be set out symmetrically with each are and laid to regular line and pattern as required.
• To tap the files firmly with a rubber mallet to neatly level fresh cement screed.
• All joint in floor tiles shall be truly aligned and even. Grout shall be worked well into joints so that they are completely filled. All joints shall be used plastic spacer 2 – 3 mm.
• All floor tiling shall be laid to fall to avoid pounding. All tiles shall be laid by the tile layer
• To ensure not to allow water onto new tiling until bedding and jointing have completely set.
• To ensure no traffic on flooring within 48 hours after completion.
• Tiles with any chips, cracks or otherwise defective shall not be used for the work.
8.3 Wall Tile Installation
• Reconfirm the existing reference levels and position provided at site by surveyor.
• Ensure that the existing plaster wall are vertically straight and does not exceed the wall finishing level
• Identify and mark the wall file finishes level and setting out point with the reconfirmation from the Resident Architect.
• Shift the required tiles, ordinary Portland cement and adhesive cement to the designated work area. Mix the cement and adhesive cement thoroughly with clean water.
• Apply the mortar to the back of tile and tap in into place at the required level position to the wall.
• Affix the remaining tiles ensuring a 2-3 mm spacer is used between tiles and wipe away the excessive slurry mortar that seeps out from the joint.
• Proceed the finish working area and allow a few hours for the tiles to set.
• File the wall tile joints with approved colour grout.
• Site inspection of complete wall area shall be undertaken with Resident Architect and any defect rectified
9.0 CONSTRUCTION PHASING AND WORKFLOW
During secant wall and bored piling construction, excavation for ground anchor installation and basement formation will commence in available areas, generally moving from grids 27/H towards 1/A.
10.0 TRAFFIC MANAGEMENT AND MONITORING
The Logistic Manager and the traffic management contractor shall be responsible for the management and control of the traffic in and out from the construction site.
11.0 SAFETY PROGRAMME
Please refer to PHOS-HS-010 Health and Safety Plan.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.1 for the Inspection and Test Plan and Appendix 15.2 for the Checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan
15.0 APPENDICES
15.1 Inspection and Test Plan
15.2 Inspection Checklist Form
15.3 Job Safety Analysis
CERAMIC/HOMOGENEOUS TILING
TABLE OF CONTENTS
1.0 WORK ORGANISATION
2.0 DESIGN CONSTRAINTS AND COORDINATION
3.0 CONTRACTING METHODS
4.0 PROCUREMENT METHODS
5.0 RESOURCE PROVISIONS
6.0 LOGISTICS PROVISIONS
7.0 MATERIAL MANAGEMENT SYSTEMS
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
9.0 CONSTRUCTION PHASING AND WORKFLOW
10.0 TRAFFIC MANAGEMENT AND MONITORING
11.0 SAFETY PROGRAMME
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
13.0 INDUSTRIAL RELATIONS POLICIES
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
15.0 APPENDICES
1.0 INTRODUCTION
This Work Method Statement is to describe the materials and procedures for the installation of tiling works This method statement also describes the technical method of application and the sequence of works to be carried out for Private Hospital Project at Jalan Tun Razak.
2.0 DESIGN CONSTRAINTS AND COORDINATION
Not Applicable.
3.0 CONTRACTING METHODS
Since PCSB is liable for the performance of any Sub-contractor, it is vital that only companies with proven track records in the relevant activity will be engaged as Sub -contractors.
It is acknowledged that before any part of the works can be sublet, the approval of the Employer’s Representative is required.
The Conditions of Contract have been reviewed by PCSB and particularly those conditions in respect of Sub-contractors. The conditions are bespoke for this project and therefore be required to be reflected in any form of Sub-contract utilized on the project.
Please refer to PHOS-CN-010 to PHOS-CN-030 for the Contract Procedures.
4.0 PROCUREMENT METHODS
Please refer to PHOS-PR-010 to PHOS-PR-030 for the procurement procedures.
5.0 RESOURCE PROVISIONS
5.1 Manpower/Labour
The number of manpower/labour to be used during the earthworks activities have been identified in the Manpower Histogram.
5.2 Plant Equipment
Typical plant equipment to be used shall consist of:
~ Grease
~ Duct Tape
~ Levelling spirit
~ Welded holding down bolt template
~ 45 T mobile crane
6.0 LOGISTICS PROVISIONS
The logistic control shall be in accordance with the approved Site Logistic Plan and includes wheel wash facilities and traffic management.
7.0 MATERIAL MANAGEMENT SYSTEMS
Please refer to PHOS-CP-040 for the Material Control Procedure.
8.0 CONSTRUCTION METHODS AND TECHNOLOGY
8.1 Surface Preparation
• To check and survey site, layout marking and setting.
• Screed shall be laid after concrete slab has been thoroughly roughened, cleaned, wetted and spread with a layer of neat cement slurry. Screed shall be 1:3 cement and sand mixture. The setting bed for floor tile shall be of neat cement grout of the right consistency.
• Edge restraint is normally necessary, it serve to restraint lateral movement of the tiles. All cutting of tiles by high – speed cutter is to be neatly carried out and suit site formation/edge.
8.2 Floor Tile Installation
• Unload of tiles by mechanical means and stored. Each tile shall be loaded into trolley and transported to area to be laid.
• To unload place and lay tiles by hand into position over neatly cement screed
• A control joint shall be established with regard to structure location and tiles are not to be set out symmetrically with each are and laid to regular line and pattern as required.
• To tap the files firmly with a rubber mallet to neatly level fresh cement screed.
• All joint in floor tiles shall be truly aligned and even. Grout shall be worked well into joints so that they are completely filled. All joints shall be used plastic spacer 2 – 3 mm.
• All floor tiling shall be laid to fall to avoid pounding. All tiles shall be laid by the tile layer
• To ensure not to allow water onto new tiling until bedding and jointing have completely set.
• To ensure no traffic on flooring within 48 hours after completion.
• Tiles with any chips, cracks or otherwise defective shall not be used for the work.
8.3 Wall Tile Installation
• Reconfirm the existing reference levels and position provided at site by surveyor.
• Ensure that the existing plaster wall are vertically straight and does not exceed the wall finishing level
• Identify and mark the wall file finishes level and setting out point with the reconfirmation from the Resident Architect.
• Shift the required tiles, ordinary Portland cement and adhesive cement to the designated work area. Mix the cement and adhesive cement thoroughly with clean water.
• Apply the mortar to the back of tile and tap in into place at the required level position to the wall.
• Affix the remaining tiles ensuring a 2-3 mm spacer is used between tiles and wipe away the excessive slurry mortar that seeps out from the joint.
• Proceed the finish working area and allow a few hours for the tiles to set.
• File the wall tile joints with approved colour grout.
• Site inspection of complete wall area shall be undertaken with Resident Architect and any defect rectified
9.0 CONSTRUCTION PHASING AND WORKFLOW
During secant wall and bored piling construction, excavation for ground anchor installation and basement formation will commence in available areas, generally moving from grids 27/H towards 1/A.
10.0 TRAFFIC MANAGEMENT AND MONITORING
The Logistic Manager and the traffic management contractor shall be responsible for the management and control of the traffic in and out from the construction site.
11.0 SAFETY PROGRAMME
Please refer to PHOS-HS-010 Health and Safety Plan.
12.0 QUALITY ASSURANCE AND CONTROL PROGRAMMES
Please refer to Appendix 15.1 for the Inspection and Test Plan and Appendix 15.2 for the Checklist.
13.0 INDUSTRIAL RELATIONS POLICIES
Not Applicable
14.0 ENVIRONMENTAL MONITORING PROGRAMMES
Please refer to PHOS-EMP-001 Environmental Management Plan
15.0 APPENDICES
15.1 Inspection and Test Plan
15.2 Inspection Checklist Form
15.3 Job Safety Analysis
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