Strength of Materials

3.4 STRAIN ENERGY DUE TO SHEAR FORCE

A rectangular block of length l, height h and breadth b is being fixed at the bottom face DC and subjected to a shear force P_f(Figure 3.5).

 

 

Fig. 3.5 Rectangular block under shear force.

 

The face AB moves through a distance δl relative to the face DC as the shear force increased gradually from zero to its final value P_f Let q be the shear stress produced and ϕ be the shear strain.

 

Shear stress,
Shear strain,
∴	BB1 = δl = ϕ BC = hθ
Then,            Shear force,