A steel rod of 15-mm diameter is held snugly (but without any initial stresses) between rigid walls by the arrangement shown in the figure part a. (For the steel rod, use  = 12 10 -6 / 0 C and E = 200...

A steel rod of 15-mm diameter is held snugly (but without any initial stresses) between rigid walls by the arrangement shown in the figure part a. (For the steel rod, use
 = 1210^-6
/⁰C and E = 200 GPa.)

(a) Calculate the temperature drop
T (degrees Celsius) at which the average shear stress in the 12-mm diameter bolt becomes 45 MPa. Also, what is the normal stress in the rod?

(b) What are the average bearing stresses in the bolt and clevis at A and between the washer (d
_w
=20 mm) and wall (t =18 mm) at B?

(c) If the connection to the wall at B is changed to an end plate with two bolts (see figure part b), what is the required diameter d_b
of each bolt if the temperature drop is
T = 38⁰
C and the allowable bolt stress is 90 MPa?