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Determine the transverse reinforcement index, Ktr, for a rectangular beam with b = 18 in. and d = 21 in., four epoxy-coated No. 6 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 3 Grade 40 stirrups located every 6 in. along the span. Assume 8,000-psi lightweight concrete and a clear cover of 1.75 in.

Vertical cracks that extend almost to the zero-strain axis of a member are likely _______ cracks.

For economy, some of the bars can be cutoff where they are no longer needed.

A rectangular beam has a cross section of b = 16 in., h = 22 in., and d = 19.5 in. It is reinforced with two No. 6 Grade 60 bars. The concrete strength is 2,500 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 = 16 in., h = 22 in., and d = 19.5 in. It is reinforced with three No. 6 Grade 60 bars. The concrete strength is 5,200 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the cracked moment of inertia, Icr. The neutral axis location of the cracked beam (measured from the top of the beam) is 4.2179 in.

Development lengths are different in compression and tension.

The three main reasons for controlling crack widths are appearance, creep, and leakage.

A simply supported beam with dimensions of b = 16 in., h = 22 in., d = 19.5 in., and L = 25 ft supports a uniform service (unfactored) dead load of 1.366667 kips/ft including its own self weight plus a uniform service (unfactored) live load of 1.5 kips/ft. The concrete is normal-weight concrete. The beam is reinforced with 3 No. 6 bars. The concrete strength is 3,100 psi, and the yield strength of the reinforcement is 60,000 psi. Determine the maximum applied bending moment due to the combined service loads (dead plus live), Ma.      

A rectangular beam has a cross section of b = 14 in., h = 22 in., and d = 19.5 in. It is reinforced with two No. 7 Grade 60 bars. The concrete strength is 4,300 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the gross moment of inertia, Ig, for the beam.

A rectangular beam has a cross section of b = 18 in., h = 24 in., and d = 21.5 in. It is reinforced with four No. 6 Grade 60 bars. The concrete strength is 7,000 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the neutral axis location of the cracked beam (measured from the top of the beam).