Beer & Johnston — Introduction—Concept of Stress: Problem 1.52

1.51 Link AC is made of a steel with a 65-ksi ultimate normal stress and has a 1/4 x 1/2-in. uniform rectangular cross section. It is connected to a support at A and to member BCD at C by 3/8-in.-diameter pins, while member BCD is connected to its support at B by a 5/16-in.-diameter pin. All of the pins are made of a steel with a 25-ksi ultimate shearing stress and are in single shear. Knowing that a factor of safety of 3.25 is desired, determine the largest load P that can be applied at D. Note that link AC is not reinforced around the pin holes. 1.52 Solve Prob. 1.51, assuming that the structure has been redesigned to use 5/16-in.-diameter pins at A and C as well as at B and that no other changes have been made.