The upside-down steel A frame shown in the figure is to be bolted to steel beams on the ceiling of a machine room using ISO grade 8.8 bolts. This frame is to support the 40-kN radial load as illustrated. The total bolt grip is 48 mm, which includes the thickness of the steel beam, the A-frame feet, and the steel washers used. The bolts are size M20 X 2.5.
(a) What tightening torque should be used if the connection is permanent and the fasteners are lubricated?
(b) What portion of the external load is taken by the bolts? By the members?