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Determine the epoxy modification factor, ψe, for a rectangular beam with b = 16 in. and d = 22 in., five uncoated No. 6 Grade 60 tension-reinforcement bars placed in the top of the beam, and No. 3 Grade 40 stirrups located every 12 in. along the span. Assume 5,000-psi lightweight concrete and a clear cover of 2 in.

Determine the epoxy modification factor, ψe, for a rectangular beam with b = 16 in. and d = 22 in., three galvanized No. 7 Grade 60 tension-reinforcement bars placed in the top of the beam, and No. 3 Grade 60 stirrups located every 6 in. along the span. Assume 7,000-psi lightweight concrete and a clear cover of 1.5 in.

Determine the size modification factor, ψs, for a rectangular beam with b = 18 in. and d = 22 in., five epoxy-coated No. 8 Grade 60 tension-reinforcement bars placed in the top of the beam, and No. 4 Grade 60 stirrups located every 12 in. along the span. Assume 5,000-psi lightweight concrete and a clear cover of 1.75 in.

Determine the transverse reinforcement index, Ktr, for a rectangular beam with b = 16 in. and d = 22 in., four epoxy-coated No. 9 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 4 Grade 60 stirrups located every 12 in. along the span. Assume 7,000-psi lightweight concrete and a clear cover of 1.75 in.

Determine the size modification factor, ψs, for a rectangular beam with b = 16 in. and d = 23 in., three uncoated No. 8 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 4 Grade 40 stirrups located every 10 in. along the span. Assume 4,000-psi normal-weight concrete and a clear cover of 1.5 in.

The stress in the reinforcement is minimum at a crack.

Determine the casting-position modification factor, ψt, for a rectangular beam with b = 17 in. and d = 23 in., four galvanized No. 7 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 4 Grade 60 stirrups located every 8 in. along the span. Assume 8,000-psi normal-weight concrete and a clear cover of 1.75 in.

Once a splitting crack develops, bond strength rapidly increases unless there is reinforcement designed to restrain opening of the crack.

Unlike exact bond stresses, the average bond stresses vary from point to point between cracks.

Use ACI 318-14 Table 25.4.2.2 to determine the development length for the straight tension bars (no hooks) in a rectangular beam with b = 17 in. and d = 23 in., three galvanized No. 8 Grade 60 bars placed in the top of the beam, and No. 4 Grade 60 stirrups located every 6 in. along the span. Assume 5,000-psi normal-weight concrete and a clear cover of 2 in.