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A rectangular beam has a cross section of b = 14 in., h = 26 in., and d = 23.5 in. It is reinforced with five No. 5 Grade 60 bars. The concrete strength is 8,800 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the transformed cross-sectional area of the bars, Ast.

A rectangular beam has a cross section of b = 14 in., h = 24 in., and d = 21.5 in. It is reinforced with three No. 5 Grade 60 bars. The concrete strength is 3,400 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the cracking moment, Mcr.

Strengthening of concrete near the top of a column is due to upward migration of water in the fresh concrete.

In a tied column in a seismic region, the ties are spaced approximately the width of the column apart.

Determine the location of the neutral axis, c, for the following tied column when the largest strain in the concrete is 0.003 and the strain in the tension reinforcement is 0.003.b = 14 in.h = 20 in.Clear cover to ties = 1.5 in.Number of longitudinal bars = 6Size of longitudinal bars = No. 9Size of ties = No. 4Concrete strength = 5,000 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 60,000 psi

Misalignment of columns from floor to floor cannot cause eccentricities in columns.

Use the interaction diagrams found in Appendix A of the textbook to determine whether the following rectangular tied column with bars in 2 faces can safely support a load of Pu = 660 kip and Mu = 264.0 kip-ft.b = 22 in.h = 12 in.fc’ = 4 ksify = 60 ksiγ = 0.6ρg = 0.05

The strength reduction factor for tension controlled spiral columns is _____.

Spiral columns have lower ductility giving more warning before a failure.

A rectangular beam has a cross section of b = 16 in., h = 28 in., and d = 25.5 in. It is reinforced with three No. 7 Grade 60 bars. The concrete strength is 5,200 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the assumed modulus of elasticity of the concrete, Ec.