Shear Stresses:

(a) The maximum shear stress within a member having regard to the distribution of stresses in conformity with the elastic behaviour of the member in flexure shall not exceed the value of τ_vm given below:

τ_vm = 0.45 f_y

An average shear stress in a member calculated on the cross section of the web shall not exceed τ_va as obtained below:

τ_va = 0.4  f _y                                                                                                                                      

[Note:  A values for stiffened webs are not reproduced here as such cases are not dealt along with in this unit.

(c) The last one is cross section of the web shall be taken as follows:

(i)  For Rolled I-beams and Channels: A depth of the beam multiplied through the web thickness.

(ii) For Plate Girders: A depth of the web plate multiplied by its thickness.