Determine the size modification factor, ψs, for a rectangula…
Determine the size modification factor, ψs, for a rectangular beam with b = 18 in. and d = 21 in., five epoxy-coated No. 7 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 4 Grade 60 stirrups located every 10 in. along the span. Assume 6,000-psi lightweight concrete and a clear cover of 1.5 in.