METHOD STATEMENT FOR TRENCHING/EXCAVTION FOR CONSTRUCTION OF

Transcription

1 METHOD STATEMENT FOR TRENCHING/EXCAVTION FOR CONSTRUCTION OF Rev. No. Date REVISION HISTORY SUB-CONTRACTOR-DELCO Prepared Reviewed Approved Revision History MANAGER Status of Approval

2 CONTENTS 1.0 Purpose 2.0 Scope of Work 3.0 Definitions 4.0 References 5.0 Materials 6.0 Plant & Equipment 7.0 Safety 8.0 Prior Activities 9.0 Procedure 10.0 Responsibilities 11.0 Attachments 1.0 Purpose 1.1 To ensure that Trenching/excavation and related activities in rocky areas 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.

3 2.0 Scope of Work 2.1 This procedure is applicable to the following works associated with the project titled,. 2.2 This method statement outlines the procedures to be followed in the Trenching/Excavation for the construction of. Pipe line in rocky areas at locations shown on Contract Drawings and as directed by Client / Consultant. 3.0 Definitions 3.1 SPM Senior Projects Manager 3.2 PM Project Manager 3.3 SE Site Engineer 3.4 SU Surveyor 3.5 ESHO Environmental, Safety, and Heath Officer 4.0 References 4.1 Specifications:.. SPECS & Contract Doc. Volume 3 Section Drawings: Contract Drawings 4.3 B.O.Q Bill of Quantities. 5.0 Materials 5.1 Sheet Piles 5.2 Box Frames (as per site condition if required) 6.0 Tools, Plant & Equipment 6.1 Excavator with rock breaker. 6.2 JCB with rock breaker. 6.3 Crane 6.4 Shovel & Trucks 6.5 Surveying equipments to check level and alignments. 7.0 Safety 7.1 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. 7.2 Where possible hazards may arise from Trenching/Excavation related activities in rocky areas, the necessary safety measures will be taken to prevent accident or

4 injury at all times. This may include barriers, warning tape/ Net, signage, watchman, and proper lighting. 7.3 ESHO will enforce that Personal Protective Equipment be worn by site personnel at all times during construction activities. 7.4 Heat Stress Training will be provided. 7.5 Provisions of adequate cool drinking water, shade, and salt water tablets will be in place. 7.6 Plant & Equipment will be provided back-up alarms, lights, and all other applicable safety Devices. 8.0 Prior Activities 8.1 Trial holes shall be made to verify clearance of other service. 8.2 Obtain existing service drawings from concerned departments. 8.3 Obtain approval of Service Reservation. 8.4 Survey work, approval drawings. 9.0 Procedure First of all decide the area is rocky or not for that follow the following statements: Geotechnical strata of volcanic origin or those of volcanic origin but containing 65 % silica. Sedimentary / aqueous rocks formed by sediments chiefly deposited by water/wind/ice. Metamorphic rocks formed by metamorphic action of heat and pressure on igneous/sedimentary rocks. Soft rocks like mudstone, clay stones, soft limestone, and soft sandstone shall be classified as Rock. The opinion of ENGINEER shall be final in this regard. Excavation in rock shall be made to provide the minimum trench width as indicated on drawings. Blasting shall not be permitted under any circumstances. Hard excavation shall be carried out by ripping, drilling, wedging, chiseling using jack hammers, or by other recognized methods approved by ENGINEER. Survey work (route marking) will start after notice made to the consultant as per approved Method Statement. De-watering (if required) will start after verification of the clearance of utilities. Excavation status and level should be controlled by surveyor strictly; in case of extra excavation a procedure of backfilling will be carried as per specification. Excavation will be kept free from water. The width of trench shall be as per specification. The excavation shall continue to the formation level and compacted properly.

5 After compacting the pipe laying will start. Engineer will check the progress at intervals. Excavation in rock shall be made to provide a minimum of 150 mm clearance on each side and below all pipes & fittings. The bottom of trench shall be cushioned with well compacted soft bedding material to a minimum thickness of 150 mm below the barrel of the pipes and extending for the full width of the trench. Any soft spots shall be excavated and refilled with lean mix concrete or selected fill materials Responsibilities Site Engineer: To co-ordinate with consultant, supervise the site works and ensure quality and safety procedures are implemented as required. Foreman: To supervise the site works, Control of Manpower and ensures quality and safety procedures are implemented as required. Chief Surveyor: To supervise survey team and ensure that shop drawings are properly followed. Surveyor: To check the limits of excavation, to check the levels and alignments and to locate existing services ahead of pipe laying Chainman: To assist surveyor Operators: To operate the machineries on site and follow safety procedures as required Attachments None