Determine the required diameter of the pins at a and b if the allowable shear stress for the material is tallow = 100 mpa. both pins are subjected to double shear. a b c 2 kn/m 3 m prob. 1–81 1–82. the steel pipe is supported on the circular base plate and concrete pedestal. if the thickness of the pipe is t = 5 mm and the base plate has a radius of 150 mm, determine the factors of safety against failure of the steel and concrete. the applied force is 500 kn, and the normal failure stresses for steel and concrete are (sfail)st = 350 mpa and (sfail)con = 25 mpa, respectively. r t 100 mm 500 kn prob. 1–