A single bolted double cover butt joint is used to connect two plates which are 8 mm thick. Assuming 16 mm
diameter bolts of grade 4.6 and cover plates to be 6 mm thick. Calculate the efficiency of the joint, if four bolts are provided in the bolt line at a pitch of 45 mm. Assume grade of steel Fe410, kb = 0.55 & thread intercept shear plane.