# Guide to Design of Shear Reinforcement in a beam

#### Design of Shear Reinforcement in a beam

The beam is failed by the diagonal tension in which the cracks start from support and extend upto a distance equal to effective depth and making an angle more or less than 45 degrees.

#### Step one

Nominal shear stress

Tv = Vu/bd

Where, Vu = shear force due to design load

b = width of the beam

d = depth of the beam

#### Step two

Percentage of steel

Percent steel = Ast/bd x 100

#### Step three

Find the shear stress in concrete (Tc) for the above percentage of steel as per IS:456:2000

#### Step four

If, Tv < Tc

No shear reinforcement is required. However, nominal stirrups are provided and their spacing is determined by,

Asv/b.Sv= 0.4/(0.87fy)

Where, Sv = spacing of stirrups

Asv = Area of stirrups

In any case, the spacing should not be more than  0.75d

#### Step five

If, Tv > Tc

Sv = 0.87fy. Asv. d/(Vus)

Where, Vus = strength of shear reinforcement

#### Here’s an example of the design of Shear reinforcement of a beam:

Example of shear reinforcement of a beam

### 6 thoughts on “Guide to Design of Shear Reinforcement in a beam”

1. How to design a beam by knowing its end moments?

2. i saw a building been constructed and it has been divided into 3 different sections with the provision of expansion joints .Why the expansion joint?