How to minimize the wastage of steel through BBS
In this civil engineering article, one will get details about how to minimize wastage of steel based on drawing plan and BBS or bar bending schedule.
According to standard practice permissible wastage is 3% (1% accountable wastage/Scrap + 2% rod length not over 1.0m).
As per IS 1786 Code, the tolerances for mass of steel is provided below :-
For up to and including 10mm Dia bar – It permits +/- 7% deviation from standard weight.
For more than 10mm up to and including 16mm Dia Bar – It permits +/- 5% deviation from standard weight.
For in excess of 16mm Dia bar – it permits +/-3% deviation from standard weight.
Development of ''Bar bending'' schedule is very important prior to place the steel bars, since it facilitates to minimize the wastage up to 98%. So, traditionally, wastage of steel is 2% of which, 0.5 % is unrecoverable and 1.5% is scrap.
The wastage mainly caused when permissible wastage is 3% and provided steel is overweight over 3% then it is required to order more steel for completion of the work as wastage will be occurred throughout cutting of steel caused by standard length of bar from which the steel will be cut. It is inevitable until you purchase a precut length bar as per required length.
Wastage in Reinforcement steel may also occur because of the following factors :-
Rebar Cutting and Bending Gang.
Production of rings by the fitter without any proper and in this way excess stirrups are produced.
Cutting of bars by the fitter without considering wastage.
To get more details on steel wastage, go through the following exclusive youtube video.
Video Source: F&U-FORYOU