The beam may fail due to tension as well as compression force than permissible force. But It also fails due to shear.
After the experiment of the shear failure with main rods and without lateral reinforcement in the beam. We found the following result.
The different types of shear failure in beam are given below,
1) Diagonal tension failure

This types of failure occur at the support of the beam where shear force has a high value and moment has a low value as compared to the shear. The crack formed due to this failure makes 35 degrees with the horizontal.
2) Diagonal compression failure

This type of failure occurs at the span between support and mid-span. At this span shear force and moment show approximately equal importance and values. This type of failure makes 45 degrees to 90 degrees with horizontal.
3) Flexural tension failure.

This type of failure occurs at the mid of the beam span. Here, the value of the moment is considerably higher than shear force. This types of failure make exactly 90 degrees with horizontal.
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