How to Calculate BBS for Beams: Step-by-Step Bar Bending Schedule Guide

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    In this article, I am going to teach you how to take the BBS of steel for the Beam Section. Let us take the Section for Example.

Section of a Beam

    In a Beam, there are 4 Types of Components. They are,

1. Main Bars - These bars run throughout the length of the beam from one end to another
2. Top Extra Bars - These bars were present at the End section( On both sides of the section)
3. Bottom Extra bars - These bars were present at the Bottom of the Beam in addition to the main bar to resist tension in the member.
4. Stirrups - This is the Steel that binds all the Main and Extra bars together.

Important Note: 

    Before taking out the Quantity, please read the details given in the drawing, like how much cover, development length, grade of steel, grade of concrete, specific hook length were provided, etc., because each project the design will be different, hence we should make sure that all these are carefully read out. Here, I just take a model for you to teach how to take the quantity.

Our Consideration ( As per IS 2502)

    Grade of Steel - Fe 500

    Grade of Concrete - M20,

    Development Length - 50D, D is the diameter of the Bar

    Lap Length - 24D in Compression and 45D in Tension

    Hook Length - 135' - 12D ,  90' - 10D

    Bend deduction - 90' -2d, 135' - 3d. 

Calculation of the length of the Main Bars of Beams,

    The Cutting length of the Main is calculated by,

Top Rod Cutting Length

    Inner to Inner Dimension of the beam + Development Length - Clear cover on both sides of the Beam end.

    

Will update, come back tomorrow...