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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.

Under sustained loads, concrete undergoes creep strains and the curvature of a cross section _______. Because the lever arm is reduced, there is a small _______ in the steel force, but for normally reinforced sections, this will be minimal.

The fatigue strength of concrete is not sensitive to stress concentrations.

Compute the maximum bar spacing, s, to control for cracks in a one-way slab with 1.5 in. of clear cover and f​y​ = 52 ksi.

In order for a reinforced concrete beam to function properly (concrete resisting compression, steel resisting tension), a bond must not exist between the concrete and the reinforcement.