道路交通改道综合项目施工专项方案英文.doc

Method Statement

Document Title:

Construction of Traffic Diversion Roads

Document No.:

EXW-P011-0000-CM-CHE-MT-00068 -Rev.CD

Name & Signature
Position
Date
Prepared By:

Technical Engineer

Reviewed By:

Technical Manager

Approved By:

Project Manager

Revision History

Revision
Date
Details of revision
CA
27-Apr-
Submit for approval.
CB
28-May-
Comply with the comments from Halcrow dated on 6-May-
CC
12-Oct-
Comply with the comments from Halcrow dated on 23-Aug-
CD
20-Nov-
Comply with the comments from Halcrow dated on 18-Oct-

Section

CONTENTS

Page

1.0
Purpose
3

2.0
Scope of Work
3

3.0
Responsibilities
3

4.0
Permits and Licences
3

5.0
Sequence of Construction of Traffic Diversion Roads
4

6.0
Resources to be used for Construction of Traffic Diversion Roads
4

6.1 Reference
4

6.2 Control，Storage & Protection of Specific Materials
5

7.0
Detailed method of Carrying Out this Method Statement
5

8.0
Quality Control and Requirements
10

9.0
Health & Safety Considerations
10

9.1 General safety issues
10

9.2 Emergency Arrangement
11

9.3 Consents and Permits
11

10.0
Environmental Considerations
12

10.1 Environmental Aspects
12

10.2 Housekeeping
12

11.0
Appendices
12

Appendix A
-
Risk Assessment

Appendix B
-
Tool Box Talk

Appendix C
-
Inspection and Test Plan

Appendix D
-
Checklist Form

Section 1.0：Purpose
This method statement is to describe the procedure and techniques of construction of traffic diversion roads in a safe manner that will satisfy all the requirements.
Section 2.0： Scope of Work
This method statement describes the activities related to traffic diversion roads，including site clearance(REF:EXW-P011-0000-CM-CHE-MT-00002)，embankment(REF:EXW-P011-0000-CM-CHE-MT-00011、EXW-P011-0000-CM-CHE-MT-00006)，sub-grade(REFEXW-P011-0000-CM-CHE-MT-00011、EXW-P011-0000-CM-CHE-MT-00006)，road base(REF:EXW-P011-0000-CM-CHE-MT-00025)，asphalt work，installation of pole light(REF:EXW-P011-0000-CM-CHE-MT-00085)，traffic signal(REF:EXW-P011-0000-CM-CHE-MT-00096)，installation of sign board，safety barriers and road marking etc. These activities are covered in separated method statement.
Section 3.0：Responsibilities
The work will be carried out by CHEC，headed by the Construction Manager.
Ÿ Construction Manager – Partially responsible for the construction and arrangement of civil works，in charge of site engineer.
Ÿ HSE Engineer & HSE Officer – Responsible for HSE on site during construction，coordinate with Site Engineer，infrastructure superintendent.
Ÿ QC Engineer – Responsible for quality of structure on site during construction，coordinate with Site Engineer，request for Inspection and Testing processes and coordination with the Engineer’s Inspectors representative.
Ÿ Surveyor – Responsible for survey work and settlement monitoring work on site，coordinate with Site Engineer，the survey request process and coordination with the Engineer’s surveyor representative.
Ÿ Site Engineer –Site engineer responsible for construction of work，coordinate with HSE Engineer，QA/QC engineer，surveyor，will in charge of foremen，operators，drivers，labours，reports directly to construction manager，request for Inspection and Testing processes and coordination with the Engineer’s Inspectors representative，as well as supervisor.
Ÿ Foreman-Directly supervises the work activity on the site and has full control over the use of the labour，plant and equipment. He ensures that the work is carried out in full compliance with the specification，and in a manner that conforms to the safety requirements. He reports to the Site Engineer when the work is complete and ready for inspection.
Ÿ All personnel (operators) should be qualified and the relevant certificate should be available.
Section 4.0：Permits and Licences
Where required as per project contract specification，permits & licences shall be obtained from relevant authorities prior to start with the related works or activities.
Section 5.0：Sequence of Construction of Traffic Diversion Roads
The sequence of traffic diversion roads as shown in the following chart:

Sequence of Traffic Diversion Roads

Section 6.0： Resources to be Used for Construction of Traffic Diversion Roads
6.1 References
Ÿ QCS
Ÿ HSE plan & Project quality plan approved by SC.
Ÿ Method statements which have been approved by Engineer:
Method statement of engineering survey：EXW-P011-0000-CM-CHE-MT-00001.
Method statement of site demolition and clearance：EXW-P011-0000-CM-CHE-MT-
00002
Method statement of soil filling and compaction for road works：EXW-P011-0000-CM-CHE-MT-00011
Method statement of aggregate road base and sub-base：EXW-P011-0000-CM-CHE-MT-00025
Ÿ Approved BC Type-1 and SC Type-1 design mixes.
6.2 Control，Storage & Protection of Specific Materials
Ÿ Materials shall be stored and handled as to assure the preservation of their quality and fitness for use in the works. Even after source approval has been given materials may again be inspected and tested before used in the work.
Ÿ Each shipment of materials is loaded，should be blocked and securely fasten to avoid damages during transportation.
Ÿ The important materials should be kept clean away from oil，grease，excessive heat and out of the direct rays of the sun.
Ÿ CHEC shall take all necessary protection measures in the storage，handling and stockpiling of materials to prevent contamination of material by test.
Section 7.0： Detailed Method of Carrying Out this Method Statement
7.1 Preparation prior to work
Ÿ All equipments are tested and suitable for the current work.
Ÿ All the equipment，material，and personnel staff have been prepared in situ.
Ÿ All the equipments are functioning all time.
Ÿ Electrical power will be mainly supplied by generators. The generators will be available and placed close to the working area.
7.2 Permit shall be obtained before commence of work
Ÿ All materials and mix designs shall be approved by Engineer prior to use in construction.
Ÿ All necessary Work permits shall be obtained prior to the commencement of any activity on the site. Personnel responsible for supervising the Works on site (Engineers/Forman) shall be aware of the permit to work system and permit shall be valid throughout the entire duration of the operation.
Ÿ All equipment to be utilized on site shall have a valid Third Party Certificate.
Ÿ Competent personnel shall be responsible for lifting activities.
7.3 Checking of underground utilities
Ÿ Prior to commence of works，underground utilities shall be checking according to as-built，underground detecting reports etc.
Ÿ If there is any underground utility in designed area，proper method shall be implemented to protect the utility.
Ÿ Work permit shall be given by specific authority prior to work if any underground utility could have been found on work site.
7.4 Site Demolition and Clearance
Ÿ Refer to the latest method statement of site demolition and clearance (document no.：EXW-P011-0000-CM-CHE-MT-00002).
7.5 Soil Filling and Compaction for Road Works
Ÿ Refer to the latest method statement of soil filling and compaction for road works (document no.：EXW-P011-0000-CM-CHE-MT-00011).
7.6 Aggregate road base
Ÿ Refer to the latest method statement of aggregate road base and sub-base (document no.：EXW-P011-0000-CM-CHE-MT-00025).
7.7 Asphalt work
7.7.1 Supply and Spray of Prime Coat:
Prior to lay of the asphalt mix，prime coat of MC-70 medium curing cutback asphalt will be applied to an absorbent road base surface which will prepare a treated base as per QCS,Clause 5.12 in section 6. The Prime coat penetrates into the base and plugs the voids and hardens the top and helps hind it to lay it to the over laying asphalt course. Application of prime coat will be as follows:
Ÿ Prime coat will be sprayed over the prepared road base.
Ÿ The application rate will be between 0.75 and 1.00 lit/Sqm. and the application temperature will be between 60oC degree and 85oC degree.
Ÿ The prime coat will be cutback bitumen consisting of a 60/70 penetration grade bitumen and kerosene. The residue from the distillation test，carried out to 360oC，shall be a minimum of 55 % (by volume)，as determined by the difference method.
Ÿ If the surface is covered in wind-blown dust or fine aggregate then a power broom will be provided to remove the materials and clean the area before application of prime coat.
Ÿ The prime coat will be sprayed by well-equipped mechanical pump and mechanical distributor fixed with a tanker (truck). Blotter material will be spread from trucks operated backward so that the wheels will not travel in uncovered wet asphaltic material. When applying blotter material to an asphalt treated lane that adjoins a lane that has not been treated，a strip at least 200 mm wide along the adjoining edge will be left.
Ÿ The prime coat will be applied to 1/2 of the road width at a time and get a slight overlap of asphalt material along adjoining edges of the lanes. Thick paper will be used to protect the previous application joints and other appurtenances.
Ÿ Traffic will not be permitted on the primed surface soon than 48 hours after spray of prime coat.
Ÿ Asphalt mix will be not permitted sooner than 2 hours after application of prime coat material. If there is any excessive blotter material，dirt or other objectionable materials，the surface irregularities will be corrected before the application of the asphalt mix.
7.7.2 Supply and Laying of Base Course:
Ÿ The Asphalt BC Type -1 will be used as Base-course which will be mix according to QCS in a fully computerized Asphalt Mix plant. Asphalt Mix plant shall be approved by SC.
Ÿ The Delivery will be taken in a dumper truck and all the precautions shall be taken to protect the mix from the weather during transit.
Ÿ Top of Asphalt will be covered during delivery.
Ÿ The material delivered to site at delivery to the paver shall be not more than 163oC and less than 140oC.
Ÿ The absolute minimum temperature will not be less than 140oC.
Ÿ Then the Asphalt will be laid with auto level Asphalt Paver in designed grade and level.
Ÿ The laid material will be compacted as soon as rolling can be effected without causing undue displacement，while the temperature does not fall below 135oC.
Ÿ The asphalt course will be constructed to design levels and shall be homogeneous and even surface free from undulations，rises or depressions within the tolerances.
7.7.3 Supply and Spray of Tack Coat:
Ÿ Before laying of wearing course the surface of base course mix will be swept clean of loose material and tack coat will be applied as per QCS specification as mentioned in section 6 part 5.13.
Ÿ Tack Coat (slow setting emulsified asphalt，grade SS-1h or CSS-1h) will be applied to a previously prepared base course，to provide bond for the wearing course to the full-designated width.
Ÿ The full width of the surface to be treated will be cleaned with a power broom to remove dust，dirt or other objectionable materials.
Ÿ Immediately after cleaning the surface，the Tack Coat will be sprayed by well-equipped mechanical pump and mechanical distributor fixed with a tanker (truck).
Ÿ Application rate of Tack Coat will be applied between 0.3 to 0.5lit/Sqm and the application temperature will be between 10oC and 60oC as specified and the excessive application of tack coat will be avoided. Besides，the material will not be applied when the ambient temperature is less than 13 °C or during rain，fog，dust storms or other unsuitable weather.
Ÿ After application，the surface will be allowed to dry until it is in a proper condition of tackiness to receive the asphalt for wearing course. Until the wearing course is placed，the tack coat will be protected from damage. If the tack coat is unavoidably damaged by rain or dust，it will be dry and cleaned again by a power broom，and get inspected by the Engineer again to instruct any further actions.
7.7.4 Supply and Laying of Asphalt Wearing Course
Ÿ The Asphalt SC Type -1 will be used as wearing course which will be mix according to Part5，Section 6 QCS in a fully computerized Asphalt Mix plant.
Ÿ The plant is designed，coordinated and operated so as to continuously produce asphalt according to required design mix and requirement of site.
Ÿ The Delivery will be taken in a dumper truck and all the precautions shall be taken to protect the mix from the weather during transit.
Ÿ Top of Asphalt will be covered during delivery.
Ÿ The material will be delivered to site at delivery to the paver shall be not more than 163oC and less than 140oC.
Ÿ The absolute minimum temperature will not be less than 140oC.
Ÿ The Asphalt Mix material SC-Type 1 will be laid by asphalt finisher as per design grade and level.
Ÿ The laid material will be compacted as soon as rolling can be effected without causing undue displacement，while the temperature does not fall below 135oC.
Ÿ The asphalt course will be constructed to design levels and shall be homogeneous and even surface free from undulations，rises or depressions within the tolerances.
Ÿ The material shall not be applied when the ambient temperature is less than 13oC or during rain，frog dust storm or other unsuitable weather.
7.7.5 Spreading and Rolling:
Ÿ The bitumen mix will be feed to pavers by end tipping of truck the equipment of spreading and finishing of mixture the sand bitumen will be of an approved mechanical，self-powered electronic controlled floating screed type capable of spreading and finishing to mixture true to line and grade as required.
Ÿ Break down rolling will immediately follow the rolling of the longitudinal joints and edges rollers will be operated as close to the paver as possible to obtain adequate density without causing un-due displacement.
Ÿ After Break down rolling the intermediate rolling will be started while the paving mix is still hot. Pneumatic rollers will be used continuously until all of the mix places have been thoroughly compacted.
Ÿ Final rolling will be performed by tandem rollers while the material is still warm to remove the roller marks by obtaining permission from Engineer. After compaction of final rolling the smoothness density and thickness will be checked and any irregularity in density and thickness will be corrected as directed by Engineer.
7.8 Road marking and sign boards：
Ÿ Road marking shall be done after finishing the asphalt work to divide the roads into several lanes for traffic use.
Ÿ The materials used for road markings shall be approved by Engineer.
Ÿ Before painting the markings，surveyors will set out the direction of the marking lines and areas.
Ÿ Road marking materials will be heated and melted on site and then