The channel shape cross-section and the rectangular cross-section shown in the Figure are made of materials with elastic-perfectly plastic behaviour. The yield stress of the material used for the channel shape cross-section is ay = 418 MPa, whereas that used for the rectangular cross- section is 0.70%. Compute the thickness of the web, t, of the channel shape section if the two cross sections have identical plastic bending moment about the z-axis. In Figure h=84 mm, b=46 mm, a=11 mm, H=84 mm, d= 46 mm Ele h b H Part a) 1. The numerical value of plastic section modulus of the solid rectangular section is mm 2. The numerical value of plastic moment of the solid rectangular section is N.mm Part b) calculate the value of t The numerical value of t can be calculated as mm