Method Statement for Construction of Cast-in-Situ Concrete for Building Structures

CONTENTS

1. Purpose

• Scope of Work

• Definitions

• References

• Materials

• Tools, Plant  & Equipment

• Safety

• Prior Activities

• Procedure

1. Responsibilities

1. Attachments

1. Purpose

1. To ensure that the Cast-In-Situ Concrete Building Structures 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.

• 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 construction of cast-in-situ concrete for building structures.

• Definitions

3.1       CM      Construction Manager

3.2       SE       Site Engineer

            3.3       CS       Chief Surveyor

            3.4       ME       Material Engineer

            3.5       ESHO  Environmental, Safety, and Health Officer

            3.6       ITP      Inspection Testing Plan

            3.7       AHA     Activity Hazard Analysis

            3.8       JHA     Job Hazard Analysis

• References

         4.1       Specifications:             Volume 3 – Section 9 – Part A – General, Civil and

                                                         Mechanical Infrastructure (Section 401)

            4.2       Drawings:                    Volume 2 – Section 8 – Part D – Architectural and Structural

            4.3       BOQ:                           Bill Nos. 12, 13, 14, 15, 16, & 17.

• Material         

• Concrete Grades 40/20/M
  • Curing Compound (resin based)
  • Polythene Sheet
  • Hessian Cloth
  • Formwork/Shuttering
  • Warning Tapes
  • Traffic Cones
  • Traffic Lights
  • Safety Barrier
  • Steel Reinforcement
  • PVC Spacers

• Tools, Plant & Equipments

• Crane
  • Concrete Mix Trucks
  • Concrete Pump
  • Concrete Vibrators
  • Surveying Instruments
  • Ladders
  • Concrete Temperature Gauge
  • Slump Cone and Cube Moulds
  • Drilling Machine
  • Electrical Saw
  • Hand Tools, Saws, Hammers, etc.
  • Power Bending Machine
  • Steel Cutter
  • Personal Protective Equipment (PPE)
  • Power Floater
  • Water Tanker
  • Measuring Tape
  • Spirit Level
  • Concrete Chisel
  • Carpenter Chisel
  • Plastic and Steel Trowels
  • Broom
  • Wire Nails
  • Air compressor
  • Generator
  • Galvanized Binding Wire
• 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.

• 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 tablets will be in place.

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

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

• Prior Activities

• Final approval for the construction of the cast-in-situ concrete structures should be obtained from the Engineer, through the shop drawings submittal process.

• Surveying instruments will be calibrated.

• Requests will be made for joint survey of element location, and checking of steel reinforcement and formwork.

• Procedure     

• Exact location of the concrete elements will be determined by the surveyor according to the approved shop drawings.

• The formwork for the concrete elements will be erected according to the sizes approved in the shop drawings and shall be fixed and supported properly.

• The steel reinforcement bars, cut and bent according to approved bar bending schedule, will be fixed as per approved shop drawings.

• Specified minimum cover shall be provided to steel reinforcement bars by using approved PVC spacer.

• Levels and alignments will be checked to confirm accuracy as per approved shop drawings.

• Before any concrete is placed the formwork shall be thoroughly cleaned and washed out with water and by air pressure using an air compressor.

• Once all pre-pour aspects are checked and found acceptable by the Engineer, concrete will be poured to the levels shown on the shop drawings.  The poured concrete will be finished smooth by using a steel trowel and/or power floater, as required.

• The concrete shall be protected by polythene sheet after finishing and wet hessian covered with polythene sheet after final set.

• Concrete surface shall be kept continuously and thoroughly wet for a curing period of seven days.

• The concrete shall be further cured by applying the approved resin based curing compound immediately after removing the polythene sheet and hessian cloth, in accordance with Clause 401.16.1 of the contract specifications.

• Testing of concrete (cubes) shall be carried out as detailed in Item 3.6 of the attached ITP.

• The formwork will be removed after the duration specified in the contract specifications and after receiving the approval from the Engineer.

1. Responsibilities

1. The CM will coordinate with SE to 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 approved material submittals.

1. It is the site supervisor’s responsibility to organize the work in a safe manner to ensure that safety and 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.