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 = 20 in., three uncoated No. 8 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 3 Grade 60 stirrups located every 6 in. along the span. Assume 6,000-psi lightweight concrete and a clear cover of 1.5 in.