Procedure Of Re-bar fixing

Hi,

some facors which are affecting the productivity of rebar fixing :-

condition of the working area

nubmer of available steel fixers

effecitncy of the steel fixers

number of the assistants

number and condition of the requered equepments and tooles for lifing, cuttig , bending.......the rebar

complexity of the reinforcement

the diameter of the steel bar

Regards

Dear Arman

I am a Quantity Surveyor , in estimation dept and i want to cross check the quantities which i have calculated

Like concrete, Rebar, Formwork based on Builtup area or any thumb rule.

I just want to check that i am not making a major mistake in Calculations...

Thankyou

Dear Arman

Can you share "Productivity Rate" with me also , It will help me too...

My email Add - [email protected]

regards

Abhishek

Jim,



What’s your email ad?





Arman

Hi Jim,



I’m not really one of those experienced professionals that you expected to reply. But like you, I am also interested to improve further my knowledge regarding the world of productivities and the factors affecting those productivities.



I would like to share my experience as follows:



>Foundation Type: Building Mat Foudation

>Slabs/Foundations Steel Fixing Productivity: 20 manhour/ton (High) and 30mh/ton (low)

>Equipment Used: 25t Mobile Crane but only 1/3 of the area is within working radius of the crane (NO TOWER CRANE).

>Tools Used: Chain pullers for alignment of installed rebars and air compressor for cleaning prior to pouring.



Works Inclusive: Unloading of rebars from delivery truck using mobile crane then sorting, installation of spacers & chairs, clean-up prior to conrete pouring using compressed air, alignment of installed rebars.



Works Exclusive: Fabrication, loading of rebar from fabrication to delivery truck.



Working Hours/day: 8 productive hours exclusive of breaktimes.





IMPORTANT NOTES:



1. If you try to look at the productivity of the same activity published here PP Production-Rates,you will notice that it is way very different. It is because I don’t know how it is being derived or where it is coming from.I have no idea why is it so, rather, that is what I wanted to find out actually. The factors that affect that specific productivity;

2. You will also notice that I specified the number of productive hours/day. It is because I have records in one of our previous projects that steel fixing during overtime hours their productivity was faster than the figure I specified above; and

3. Lastly, the fast production rate is what I believe was my perfect and ideal condition rate. The labour effectiveness factors that I gathered for my low rate are still inconclusive being subject to further data gathering, comparissons and evaluations.



PROCEDURE OF REBAR FIXING:



1. Survey set-out (Coordinates and elevation);

2. Set-up temporary scaffolding systems (Beam height above 1m);

3. Fix beam bars;

4. Fix mat bottom bars;

5. Install steel chairs;

6. Fix mat top bars;

7. Fix column rebar stumps;

8. Alignment using chain pullers;

9. Survey final check;

10. Concrete pour bottom slab of mat foundation;

11. Form and pour beams;

12. Water proofing;

13. Backfilling and compaction; and

14. Slab on Grade Works.

10. Quality check and sign off







Regards,





Arman