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A beam is singly reinforced with the reinforcement in two rows. The bottom row contains 6 No. 6 bars at a depth of 22 in. The top row contains 4 No. 7 bars at a depth of 17 in. Determine the effective (centroidal) depth, d, of the steel.

An elastic calculation gives a good estimate of the concrete and steel stresses at service loads.

Cracks that extend upward as high as the neutral axis and sometimes into the compression zone are likely _______ cracks.

A simply supported beam with dimensions of b = 16 in., h = 28 in., d = 25.5 in., and L = 24 ft supports a uniform service (unfactored) dead load of 2.266667 kips/ft including its own self weight plus a uniform service (unfactored) live load of 1.0 kips/ft. The beam is reinforced with three No. 7 Grade 60 bars. The concrete strength is 4,900 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the effective moment of inertia, Ie.The cracked moment Mcr = 91.47 kip-ft, and the maximum applied bending moment due to the combined service loads (dead plus live) Ma = 235.2 kip-ft. The neutral axis location of the cracked beam (measured from the top of the beam) is 5.6915 in.

A simply supported beam with dimensions of b = 14 in., h = 24 in., d = 21.5 in., and L = 15 ft supports a uniform service (unfactored) dead load of 1.85 kips/ft including its own self weight plus a uniform service (unfactored) live load of 0.8 kips/ft. The beam is reinforced with two No. 8 Grade 60 bars. The concrete strength is 5,800 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the effective moment of inertia, Ie.The cracked moment Mcr = 63.97 kip-ft, and the maximum applied bending moment due to the combined service loads (dead plus live) Ma = 74.53 kip-ft. The neutral axis location of the cracked beam (measured from the top of the beam) is 4.9896 in.

A rectangular beam has a cross section of b = 18 in., h = 30 in., and d = 27.5 in. It is reinforced with two No. 5 Grade 60 bars. The concrete strength is 9,700 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 2.9554 in.

A rectangular beam has a cross section of b = 18 in., h = 24 in., and d = 21.5 in. It is reinforced with two No. 6 Grade 60 bars. The concrete strength is 6,400 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 3.3587 in.

Determine the bar-spacing factor, cb, for a simply supported rectangular beam with b = 24 in. and No. 3 stirrups. This beam has three No. 7 bars as longitudinal reinforcement. The clear cover is 1.9 in.

Cracks due to shear are unable to cross into the compression zone of the member.

Universally accepted crack widths are specified in ACI 318.