Method Statement for Placing of Surface Protection Material

CONTENTS

1. Purpose

• Scope of Work

• Definitions

• References

• Materials

• Tools, Plant  & Equipment

• Safety

• Prior Activities

• Procedure

1. Responsibilities

1. Attachments

1.0       Purpose

1. To ensure that placing of surface protection material and related activities are executed safely and in accordance with the contract requirements and that all quality assurance/control activities are conducted in a systematic manner, works are inspected and conformance is verified and documented.

2.0       Scope of Work

• This procedure is applicable to the following works associated with the Project titled, “New 2K Runway – Main Runway Works” – Contract Number NRTW-1008-CN.

• This method statement outlines the procedures to be followed in the placing of Surface Protection Material at locations shown in the contract drawings and as directed by the Engineer.

3.0       Definitions

• CM                  Construction Manager
  • SE                   Site Engineer
  • CS                   Chief Surveyor
  • ME                   Material Engineer
  • ESHO              Environmental, Safety, and Health Officer
  • ITP                  Inspection and Testing Plan
  • AHA                 Activity Hazard Analysis
  • JHA                 Job Hazard Analysis

• References

• Specifications:             Volume 3 – Section 9 – Part A – General, Civil and Mechanical Infrastructure

• Drawings:                    Volume 2 – Section 8 – Part B – Civil, Mechanical and Navaids

• BOQ:                           Bill No. 3

• Materials

• Surface Protection Material
  • Bituminous Prime Coat
  • Water
  • Warning Tapes
  • Temporary Signs
  • Traffic Cones
  • Traffic Lights
  • Safety Barriers
  • Grade Stakes

• Tools, Plant & Equipment

• Mixing Plant for Surface Protection Material
  • Wheel Loaders
  • Dumper Trucks
  • Graders
  • Vibrating Rollers
  • Pneumatic-Tyred Rollers
  • Water Tankers
  • Air Compressors
  • Personal Protective Equipment

7.0       Safety

• Prior to the commencement of any activities, the workforce will receive an induction talk on the project site safety requirements. This induction talk will include both activity safety issues, as well as general safety requirements.

• Where possible hazards may arise from filling activities, the necessary safety measures will be taken to prevent accident or injury at all times. This may include barriers, warning tape/ net, signage, watchman, and proper lighting.

• Where work upon existing services may be required, the necessary work permits and safety equipment should be obtained prior to the activity commencement.

• Front line supervisor will ensure that Personal Protective Equipment is worn by site personnel at all times during construction activities.

• Heat Stress Training will be provided.
  • Provisions of adequate cool drinking water, shade, and salt water tablets will be in place.

• Plant & Equipment will be provided back-up alarms, lights, and all other applicable safety devices.

• For AOA work, safety requirements as defined per Section 107 will be implemented. Specific safety training will be provided to personnel for AOA work.

8.0       Prior Activities

• The surveyor will locate and mark all live services that are present in the site (This includes above ground services as well as buried services). These services (electric, telephone, gas, oil, chemical, water, etc) will be clearly marked using stakes and warning tapes. Near these services, special precautions will be undertaken and coordination with the Engineer will be carried out to avoid any damages during the filling and compaction process. Any existing service if exposed during previous excavation will be clearly marked, protected, and properly supported during all activities.

• The surveyor will verify that the OAJ prepared formation level is within +/-25mm tolerance as required by Clause 201.2.7 and Table 331.12.1 of the Project Specifications.  The surveyor will prepare plans and sections accordingly and submit to the Engineer for verification.

• Procedure

Surface Protection Material placing operations will be carried out to comply with the requirements of the latest and approved OAJ-JV Inspection Test Plan 1008-OAJ-ITP-1042, which in turn reflects the testing requirements of the contract specifications.

9.1       Placing of Surface Protection Material

• The Surface Protection Material shall comply with Clause 200.13 of the Project Specifications and the ME will inspect and test the material accordingly and periodically as per the requirements of the approved ITP.

• Prior to the commencement of any Surface Protection Material placing operations, the grade checkers will check the formation levels and will mark fill levels as required per project specifications.  The existing formation will be prepared and proof rolled in accordance with Clause 331.7 of the Project Specifications.  Afterwards, just prior to placing the Surface Protection Material, the existing formation level layer will be pre-wetted to increase bonding with the new one.

• The Surface Protection Material will be mixed with water at a designated approved stockpile area.  The water used for mixing the material will comply with Clause 200.12A of the Project Specifications, and moisture will be kept within the range of -0% to +2% of the optimum moisture content.

• The Surface Protection Material will then be transported, via dump trucks, to designated areas where it will be spread and levelled by graders and compacted initially by steel drum rollers.

• Should the need arise to adjust the moisture content again, water will be sprayed uniformly using water tanker equipped with sprinkler bars.

• The grader will have a second and third run (if required) accompanied by the steel roller until levels are reached.  Thickness of the layer will conform to the contract drawing “Typical Section Details” and if needed, will be adjusted according to field testing and related results.  The finished surface will be moistened (within the required optimum moisture content), not dampened, and compacted with a pneumatic tyred roller to have a better cohesive layer and achieve the required compaction of laboratory Maximum Dry Density of not less than 95%.

• Preliminary trials will be conducted at the start of the works to determine the optimum number of passes of compaction and control the pre-wetting and water spraying for optimum moisture content.

• Maximum Dry Density and in-situ CBR testing will be performed in accordance with Clause 200.13 of the Project Specifications, at a specified frequency of one test each per 500 m² and 25,000 m² respectively.

• The surveyor will verify that the top of design surface of the Surface Protection Material is of such smoothness that, when tested with a 4.8 m straightedge applied parallel and at right angles to the centreline, it shall not show any deviation in excess of 25 mm, or shall not be more than +50/-0 mm from true grade as established by grade pins, in accordance with Clause 200.13 of the Project Specifications, prior to the submission to the Engineer for approval.

• In all areas of fill, the SE will verify that no visible voids are formed within the fill.  If necessary, materials will be mixed to ensure an overall grading which will not result in visible voids being present in the fill.  The SE will ensure that all surfaces are well-closed and free from cracks and loose material.

• Where indicated on the contract drawings the Surface Protection Material layer shall be applied with a prime coat of MC 30 petroleum bitumen as described in Clause 331.31 of the Project Specifications, except that the application shall be up to 1.60 litres per square meter.

Note:   Trials of the proposed Surface Protection Material shall be undertaken within six months of commencing the works.  The trials shall demonstrate the approved method of placement, compaction and finishing.

1. Responsibilities

1. The CM will coordinate with SE and ensure that the necessary resources to implement the approved method statement, JHA, and AHA have been allocated to the task.

1. The SE will ensure that the site preparation activities are conducted according to the approved method statement, JHA and AHA.  The SE will also ensure that all in-situ tests, as required by the ITP, are implemented.

1. The ME will ensure that the materials being used are in accordance with the project specifications and the approved material submittals.

1. It is the Front Line Supervisor’s responsibility to organize the work in a safe manner to ensure the safety and that protective equipment are being properly utilized.  He must also ensure that the AHA and JHA are implemented and the approved method statement procedure is followed and the ITP is applied.