MS for Surcharge at Pre-Loading Area

Penta-Ocean Construction Co., Ltd.Ref.: MS/FND/038

Shatin to Central Link Contract 1102 Hin Keng Station and Approach StructuresRevision : -Date: 10-2-2014

Method Statement for Demolition & Modification Works at Existing Retaining Wall RW5Page: 28 of 30

Method Statement for Demolition &

Modification Works at

Existing Retaining Wall RW5

For

Hin Keng Station & Approach Structures, Contract No. 1102

This document contains confidential information of Penta-Ocean Construction Co., Ltd. and shall not be copied or amended without approval of the Project Manager

RevIssue DateStatusPrepared by Reviewed by Reviewed by

Engineer / Construction ManagerQA ManagerSafety Manager

-10-2-20141st Submission

Thomas Tiu

Helen Tong

Alex Lam

Date: 10-2-2014Date: Date:

Reviewed by Approved by

Senior Construction ManagerProject Manager

Colbert Cheung

Wilson Chu

Date: Date:

ContentPage

1. The Scope of Works 32. Method and Sequences of Construction ..103. Plants and Labour Resources 234. Safety and Environmental Mitigation Measures ..235. Fire Protection Measures .23

Appendices: Appendix 1 Catalogue of Remote Robot BROKK 90 Appendix 2 Catalogue of Wire Cutting Machine Appendix 3 Catalogue of Coring Machine Appendix 5 Catalogue of Excavator Backhoe Appendix 6 Catalogue of 30Ton Mobile Crane Appendix 7 Rick Assessment Appendix 8 Inspection and testing Plan

1. The Scope of Works

This method statement outlines the procedure for demolition works and modification works at existing retaining wall RW5 for mini-pile construction, RC platform Construction and Modification Works of RW5.

Figure 1 Location Plan of Demolition Work at Existing Retaining Wall RW5

Figure 2 Demolition Work at RW 5 (Bay 1 to 4 Plan View)

Figure 3 Demolition Work at RW 5 (Bay 1 to 4 Wall Elevation)

Figure 4 Demolition Work at RW 5 (Bay 1 to 4 Wall Section)

Figure 5 Modification Work at RW 5 (Bay 5 to 7 Plan View)

Figure 6 Demolition Work & Modification at RW 5 (Bay 4 to 7 Wall Elevation)

Figure 7 Demolition Work & Modification at RW 5 (Bay 4 to 7 Wall Elevation)2. Method and Sequences of Demolition Works

The working sequences will be as follows:1. Demolish the wall stem (Bay 4 to Bay 7)2. Extend the wall toe (Bay 5 to Bay 7)3. Demolish the wall stem (Bay 1 to 4) and made god the top of wall for RC Platform Construction.4. Demolish 3 nos of re-bays at the toe for mini-pile construction (Bay 2 to 4)

2.1. Demolition of Wall Stem (Bay 4 to Bay 7)i) Clear off the ballast and sub-ballast to formation level.ii) Saw cut a 50m depth groove on concrete surface along the cut line as per the Figure 8.iii) The upper portion will be hacked / broken by a mini-breaker from top down to approx. 0.6m above the groove as per the Figure 9.iv) Hack / Break the lower 600mm height portion with handheld breaker as per the Figure 10.v) Cleaning of concrete debrisvi) Cut and remove abandoned reinforcement except the starters

2.2. Extension of Wall Toe (Bay 5 to Bay 7)i) Expose the existing wall toe by excavator/backhoeii) Place blinding concreteiii) Drill in holes for anchor reinforcement (Dia. 48mm holes, 1135mm depth @150c/c at top row and Dia. 32mm holes, 710mm depth @150c/c at bottom row as per the Figure 11.)iv) Insert T25 anchor reinforcement and grout with HILTI HY-150 at bottom rowv) Insert T40 anchor reinforcement and grout with HILTI HY-150 at top rowvi) Roughen the concrete surface for preparing the construction joint.vii) Fix reinforcements as per working drawing.viii) Fixing the side formwork for extension of wall toe,ix) Place concrete

2.3. Demolition of Wall Stem (Bay 1 to 4)i) Demolition of upper portion by wire cutting method or saw cutting method. The wall will be divided into number panels, each panel max weight of 8ton (approx. size 2m(L) x 0.7m(W) x 2.4m(H) as per the Figure 12ii) Core 2 numbers of 100mm diameter holes on each panel for lifting and core a 50mm diameter hole at the intersection of vertical cut-line and horizontal line as per the Figure 13.

iii) Wire cut along horizontal cut line to divide the panel from lower wall stem as per the Figure 14.iv) Attach Lifting slings go through the cored holes and hold the panel before vertical cutting as per the Figure 15v) Wire cut or saw cutting along the vertical cut-line. The panel will be lifted and laid inside the dump truck for disposal.vi) Excavate the sub-ballast to expose the wall back at lower 1000mvii) Hack / break the lower 1m height portion with handheld breaker as per the Figure 16.viii) Cut and remove abandoned reinforcement except the starters. Bend-in the top of start into the wall and make-good the wall head with concrete or non-shrink grout as per the Figure 17.2.4. Demolition at part of wall tow to form 3 nos of re-bays for mini-pile construction (Bay 2 to 4)2. i) Expose the existing wall toe at mini-pile cap locations as per the Figure 18.ii) Hack / break the wall toe at mini-pile location with handheld pneumatic breakeriii) Cut and remove the abandoned reinforcements.iv) Make good the concrete edge to form the re-bay to suit the pile cap size.

Figure 8 Demolition of Wall Stem at RW 5 (Bay 4 to 7)

Figure 9 Demolition of upper Wall Stem at RW 5 (Bay 4 to 7)

Figure 10 Demolition of Lower Wall Stem at RW 5 (Bay 4 to 7)

Figure 11 Extension of Wall Toe at RW 5 (Bay 5 to 7)

Figure 12 Paneling of Wire Cutting (Max. 8 ton in weight) (Approx. 2m (L) x 2.1m (H) x 0.7m (W))

Figure 13 Coring Holes for Wire Cutting at RW5 (Bay 1 to Bay 4)

Figure 14 Cutting and Divide a Panel from Wall along Horizontal Cut-line

Figure 15 Removing the Wall panel by Cutting along the Horizontal Cut-Line

Figure 16 Demolish the Lower Wall Stem at RW5 (Bay 1 to Bay 4)

Figure 17 Make Good Wall Top to Suit RC Platform Construction

Figure 18 Hack-off the Wall Top and Forming a Re-bay for Mini-pile Construction3. Plants and Equipments

i) Plants and Equipments1. Cherry Picker 1 no.2. Mini-breaker1 nos3. Remote Robot1 nos4. Excavator 1 nos.5. 110V Hand held breakers2-3 nos.6. Wire Cutting Machine / Saw Cutting machine 1 set7. Pneumatic breakers with Air Compressor1 set.8. 300Ton Mobile Crane1 no.

4. Safety and Environmental Mitigation Measures

i) All workers are required to wear safety helmet, safety shoe and reflective safety vestii) Pre-work briefing, safety induction course and safety tool box training shall be provided to the workers prior commencement of the work. iii) Crane lorry should be equipped with safe load indicator. Examination of crane in accordance with F&IU Regulationiv) All lifting gears should be certified by RPE before use.v) Rigger should select the suitable lifting gear, i.e. Chain sling, wire/nylon rope according to the safe working load.vi) Lifting operation will be aborted in case of Typhoon Signal No. 3 or above, Amber / Red Black Rainstorm and Thunderstorm Warning is/are hoisted.;vii) Person-in charge and Banksman will use walky-talky to ensure good communication with rigger and crane lorry operator.viii) Competent operator shall be employed and he shall check crane conditionix) Provide proper access and supervisionx) Regularly check the generator & electrical tools by registered electrician; Provide proper earth-rod; provide emergency stop bottom; provide fire extinguisher; Stop the generator when refuelling.

5. Fire Protection Measures

i) Smoking is prohibited on siteii) Provide sufficient fire extinguishers in good conditions at welding works.iii) The generator and MCB box will be setup in construction site.

Appendix 1 Catalogue of Remote Robot BROKK 90

Appendix 2 Catalogue of Wire Cutting Machine

Appendix 3 Catalogue of Coring Machine

Appendix 4 Catalogue of 30Ton Mobile Crane

Appendix 5 Catalogue of Excavator

Appendix 6 Rick Assessment

Appendix 7

Inspection and testing Plan