Learn to calculate the cutting length of stirrups in bean & column

If there is sufficient depth for beam, the shear strength is increased significantly. When the depth is insufficient, steel stirrups should be added to enhance the shear strength of the beam.

The stirrup stands for one piece of steel that is bent into a rectangular shape. The stirrup generally wraps around the bottom and top bars of the beams.

In the following civil engineering tutorial, you will learn how to work out the cutting length of stirrups in beam and column.

To perform the calculation, initially, it is required to get the dimensions of beam or column. These dimensions involve width and height of beam. After that, measure all the four sides of the beam. Then, work out the width and height of stirrups (c/c distance). It can be obtained by deducting clear cover from total length and width. At the end, provide these values in a formula to measure the cutting length of stirrups.

Given below, the details of steel alongation :-

a. 1d for 45 degree bend in stirrups.
b. 2d for 90 degree bend in stirrups.
c. 3d for 135 degree bend in stirrups.

The calculation is done on the following example :-

Also Read: The steps involved in producing stirrup in column

There is a beam with width 500 mm and height 400 mm. The diameter of the stirrups bar is 10 mm. The clear cover in the beam is provided as 35 mm.

Solution:

Initially, find out the length of x and y as follow :-

Length of X = Width – 2 (half the diameter of the bar) – 2 (clear cover) = 500 – 2(5) – 2(35) = 420 mm

Length of Y = Height – 2(Half the diameter of the bar) – 2(Clear Cover) = 400 – 2(5) – 2(35) = 320 mm

To determine the cutting length of stirrup, the following formula is used :-

Formula = (2 x X) + (2 x Y) + 2(10d) – 3(2d) – 2(3d)
= 2(420) + 2(320) + 2(10x10) – 3(2x10) – 2(3x10)
= 840 + 640 + 200 – 60 – 60
= 1680 – 120 = 1560 mm or 1.56 m

Video Source: Civil Engineering