Method statement

Company Name
Method Statement of Concreting for Zone 1&3,(+) 9.0m level RC decking Slab @ bridge  GL 6-8/F-H	Doc. No: ##############  (R0 dtd.1.12.2018)
	Issue No: 1	Total No. of Sheets: 6

  

Project:	############Towers -TA (B2+B1+G+M+34+Roof) TB (B2+B1+G+M+38+Roof) Plot no : ######3Dubai
Consultant	############

ISSUE HISTORY
Issue No.	Revision Status with date	Description of Change

APPROVALS
Prepared by:	Reviewed by:	Approved by:
(QAQC Engineer)	(Construction Manager)	QA/QC Manager

CONTENTS                                                                                                                                   PAGE NO.
1.    PURPOSE	2
2.    SCOPE OF WORKS	2
3.    RESPONSIBILITY OF SITE STAFF	2
4.    MATERIAL REQUIREMENTS	2
5.    LABOUR REQUIREMENTS	3
6.   MATERIAL CERTIFICATES  &  APPROVALS	3
7.    REFERENCE CODES	3
8.    CASTING OF CONCRETE CUBES & TESTING	3
9.    ROUTINE  TESTING  OF CONCRETE	3
10. EXECUTION PROCEDURE  OF CONCRETING WORKS	4- 6
11. HOUSE-KEEPING	6
12. SAFETY	6

1.     PURPOSE

The method statement defines the step-by-step procedure of execution of concreting for Zone 1&3, (+) 9.0m level RC decking Slab @ bridge GL 6-8/F-H in Dubai ##############Towers

2.     SCOPE OF WORKS

·         Details of Materials, Approved Mix Design by Consultant Fcyl 50/20 (OPC +MS).

·         Procedure for Concreting of Zone 1 & 3, (+)9.0m level

·         Details for Transportation, Placing & Compaction

·         Frequency of Sampling & Testing

·         Details of Curing

3.     RESPONSIBILITY OF SITE STAFF

The Construction Manager/ Senior Project Engineer/ QA/QC Engineer, MEP Engineers and Safety Engineer will ensure the following:

• Reading and thorough understanding of the Approved latest Drawings & Specifications
• Familiarizing the Approved Project Specific Quality Plan Method statement, Approved Project Specific Safety Plan and Inspection and Test Report
• Organizing the required Men, Materials and Machinery at Site
• Ensuring that the Safety procedures are followed at the construction project site including analyzing the safety risks and hazards and precautions/prevention to be taken to avoid any accidents at the site.
• Supervision of the concreting works and ensuring that the work is done in accordance with the Drawings/details and Specifications, Project Specific Quality Plan, Method Statements
• Following the approved MEP – Shop drawing  for all services in the RC slab
• Engineers have to make sure that the all works executed at site is as per consultant approved drawing
• Make sure that Laboratory Technician will be present throughout the pour
• Following the Inspection and Test Plan and completion of the required Quality Checklists
• Ensuring that a high quality material is used and good workmanship is maintained throughout the works. Will visually inspect, analyze and reject any poor quality of concrete supplied by the supplier
• Works to be inspected by the consultant for final Approval prior to casting.

4.     MATERIAL REQUIREMENTS

List of Material

·         Concrete quantity of specified grade and mix for the concreting for Zone 1&3,(+) 9.0m level RC decking Slab @ bridge  GL 6-8/F-H concreting - ###### 50/20 (OPC +MS)

·         Slump Cone with tamping rod                                 -1 set

·         Thermometer                                                       -1 no.

·         Cylinder moulds, Scoop & Tamping rod                   -12 no’s, 1 no. & 1 no.

·         Water requirement                                                - as required

·         Lighting Arrangements                                           - as required

Standard Tools

·         String Line

·         Gum boots

·         Vibrator

·         Leveling Instrument

·         Spirit levels 1-2m

·         Measuring tape

·         Power Float (1 no.)

·         Masons trowels

·         Masons brushes and buckets

5.     LABOUR REQUIREMENTS

Listing of the Workers:

For RC deck slab concrete = 6 m3 total and manpower required.

a)     Mason           :02

b)     Helper           :2

c)      Carpenter      :02

d)     Steel fitter     :01

6.     MATERIAL CERTIFICATES  &  APPROVALS

• Approved mix design ####### 50/20 (OPC +MS) by############ Architects consultant and authorities.
• Approval of shop drawing for all trades
• Approval from ############ Architects consultant for all MEP trades
• Pouring approval from MEP –######## Architects consultant

7.     REFERENCE CODES

As per ############ Architects Technical Specification 03 30 00 Cast In Place Concrete.

• BS 1811    -  for concrete design and materials
• BS 812      -  for testing aggregate
• BS 5328    -  Ready Mix Concrete
• BS 1881 Standard practice for curing concrete
• Approved General specification/ BOQ
• Regulation by the authorities
•  

8.     CASTING OF CONCRETE CUBES & TESTING

• 1 set (6 nos.) test of cylinder moulds (dimension 300 X 150mm) are to be cast in 3 layers compacted with 35 blows in each layer.
• After 24 hours, the concrete cylinder has to be removed from molds and stored in curing tanks.
• The cylinder is to be tested for compressive strength at 7^th & 28^th days in accordance with ASTM C39/C39M:1 “Methods of testing concrete”.
•  

9.     ROUTINE  TESTING  OF CONCRETE

As per #############  Architect Specification in Volume – III

3.03 ROUTINE CONCRETE TESTING

Test Mix Design	Minimum Frequency RC Slab ####### 50/20 (OPC+MS)
Temperatures		As directed by the Consultant Every truck
Concrete Slump		As directed by the Consultant Every Truck
Concrete  Compressive Strength		6 cylinder per 50m³

10.  EXECUTION PROCEDURE  OF CONCRETING WORKS

10.1 CHECKS PRIOR TO START OF WORK (CONCRETE)

The CM/ PE/ SE /QC, Safety Officer and MEP Engineer or his representatives should organize and ensure the following:

• MEP – Service sleeves, conduits and box outs to be checked final for all in the RC deck slab and make sure again that it is in the correct position and places.
• Engineers have to make sure that the all works executed at site is as per consultant approved drawing
• Engineer should make sure that Laboratory Technician is present throughout the pour
• Engineer should make sure for sufficient labors, machineries, tools ,water and  lighting in the site

• That the RMC concrete supplier issues a RMC Data/Concrete Batch Sheet for each load of concrete delivery along with the following details:
• Grade of concrete for RC Slab- ######  50/20 (OPC+MS)
• Aggregate size 05-20 mm
• Admixtures (Retarder, Plasticizer)
• Minimum cement content
• Maximum water/cement ratio
• Workability
• Cumulative content details
• That the concrete mix design with the RMC data sheet is compared
• That the RMC vehicle drum rotation is of the lowest agitating speed
• That the concrete for the required slump and temperature is as per the approved mix design
• That the visual examination of concrete (like type of aggregates, color of concrete, segregation if any, etc.).
• That recording of dispatch time of concrete from the RMC plant in the delivery site is properly done
• That the distance of batching plant should be such that the concrete reaches the site within an hour for unloading the concrete.
• That for easy identification and traceability of concrete supplied and poured, a site register has to be maintained to record the D.O. no., concrete grade received, quantity, time received, pour location (floor, structural element)
• That one set of cylinder is cast from the sample taken from the same vehicle and frequency of testing concrete is as per frequency of testing concrete
• That  the gauge of water in the RMC vehicle shows water content as “full load”
• That for increasing the workability of concrete, the approval of Consultant is to be sought and the same carried out in the site only in the presence of CM/PE in charge.
• That washing is not allowed inside the site for cleaning the RMC vehicle after pouring the concrete.
• Will follow the procedure of concreting of slab subject to the consultant approval and instructions on site.
•  

10.2 CHECK FOR MANPOWER AND MACHINERY

·         Should ensure that the deployment of manpower is properly done

·         Should ensure that the pumps located reach the required destination of concrete

·         Should check the lighting arrangement

 10.3 CONCRETING OF Zone 1& 3,(+) 9.0m level RC decking Slab @ bridge  GL 6-8/F-H

The concrete deck slab consists of approximately 5 m3 of concrete to be placed in a single Pour.

Critical Specifications.

· The designed mix with approval as per the specification is Fcyl 50/20 (OPC+MS) for the RC Slab.

Brief Methodology

Activity is planned as a continuous pouring operation by bucket     

a) Minimum number of cylinder moulds

· The number of sets of cylinders to be taken is based on 1 set of cylinders for every 50 m3  of concrete poured 1 set = 6 cylinder moulds.                                                                                                                                                                                                                                                                                                                                                                                                                                                              

· These are for Compressive Strength Testing for 7 days and 28 days of curing.

b) Number of vibrators - 1 No.

c ) Precautionary Measures

·   An additional 1 no. of vibrator to be kept as a stand bye.

·   A team of mechanics and electricians will also be on stand - by duty throughout the pouring activity as a precaution against equipment or power failure. 

d) Initial Preparation and inspection prior to commencement of pour

 ·   Clean the deck surfaces with compressed air to remove all loose debris.

 ·   Ensure all MEP services are in place and secure undertaking from MEP Sub contractor

 •   Ensure all the clearances from internal facade from clad tech , ID work from Leader LLC.

·   Arrange for inspections by consultants and local authorities for final approvals.    

                                                                                 

e) Placing of concrete and compaction

By crane bucket

Quality Concerns & Control

a)  The area to be poured will be cleaned with compressed air. Concrete should be approved mix and that will be poured in compact with applying vibrators and the top surface will be finished manually with aluminum long edge trowel finish.

b)  M/S Unibeton Ready Mix technician will be available on site to test fresh concrete and to monitor cylinder making and slump test as per specification requirements.  Site quality control documentation will be prepared prior to the pour including schedules and cylinder labels etc.

c) Surface leveling will be controlled by surveyor with auto level.

d) All Supervisory staffs will be keen and alert throughout the pouring time up to the finish for quality control as well as to control all pouring related activities.     

e) Finishing of Surfaces

Hand Trowels (long aluminum) shall be used to finish the top surfaces of the RC deck slab.                                                                                           

10.3.1 Pre-concreting activities of deck Slab

The CM/PE will organize with Site Engineer, QA/QC Engineer and Safety Engineer to supervise the concreting works and ensure the following:

• Should ensure that all  required machinery (in good working condition) are placed  near the pour of concrete
• Should check and confirm the shear stud and deck sheet before the concrete.
• Should also check before concreting whether there are any gaps in deck sheet which will allow cement slurry to leak out.
• MEP – Service sleeves, conduits and box outs to be checked final for all in the slab and make sure again that it is in the correct position and places.

·       Engineers have to make sure that the all works executed at site is as per Consultant approved     drawing

·       Engineer should make sure that Laboratory Technician is present throughout the pour.

10.3.2 During Concreting of RC deck slab

• The concrete which is passed in the site checkpoint only will be poured.

10.3.3.1 Need for Compaction:

• Removal of air voids in concrete and achieve maximum density
• Ensuring intimate contact of concrete with reinforcing steel and other embedded parts

Post-concreting

• Subsequently, after the required setting time, the curing operations should be commenced as per the procedure mentioned.

Curing (Curing of exposed concrete surfaces)

Concrete is to be protected during the first stage of hardening from the harmful effects of sunshine, drying, winds, cold, rain or running water. The protection is to be applied as soon as practicable after completion of placing by covering the concrete surface with one or more of the following:

Approved curing with cold water should be sprayed on the top surface of concrete beam immediately after the initial setting of concrete. Protection will be provided by covering with Hessian cloth and Polythene sheet to avoid evaporation while curing. Curing should be continues at least up to 7 days.

11.0 HOUSE-KEEPING

The storage of materials in the work-place has to be planned properly and neatly stacked.

On a day-to-day basis, the concrete waste has to be removed from the work-place.

12.0 SAFETY ISSUES

Please refer Project Specific Safety Plan

Please refer the attached Risk Assessment documents.