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For the first few years, the time required for a corrosion cell to be established in the reinforcement is a function of concrete crack width.

A rectangular beam has a cross section of b = 14 in., h = 24 in., and d = 21.5 in. It is reinforced with two No. 7 Grade 60 bars. The concrete strength is 7,900 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the gross moment of inertia, Ig, for the beam.

A simply supported beam with dimensions of b = 16 in., h = 28 in., d = 25.5 in., and L = 17 ft supports a uniform service (unfactored) dead load of 2.166667 kips/ft including its own self weight plus a uniform service (unfactored) live load of 0.8 kips/ft. The concrete is normal-weight concrete. The beam is reinforced with 3 No. 6 bars. The concrete strength is 5,800 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.      

Universally accepted rules for maximum crack widths can be found in _______.

A simply supported beam with dimensions of b = 18 in., h = 26 in., d = 23.5 in., and L = 19 ft supports a uniform service (unfactored) dead load of 1.5875 kips/ft including its own self weight plus a uniform service (unfactored) live load of 1.1 kips/ft. The beam is reinforced with five No. 6 Grade 60 bars. The concrete strength is 7,300 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the effective moment of inertia, Ie.The cracked moment Mcr = 108.3 kip-ft, and the maximum applied bending moment due to the combined service loads (dead plus live) Ma = 121.3 kip-ft. The neutral axis location of the cracked beam (measured from the top of the beam) is 5.1659 in.

A rectangular beam has a cross section of b = 16 in., h = 30 in., and d = 27.5 in. It is reinforced with three No. 8 Grade 60 bars. The concrete strength is 7,900 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 6.0334 in.

A simply supported beam with dimensions of b = 18 in., h = 24 in., d = 21.5 in., and L = 21 ft supports a uniform service (unfactored) dead load of 1.45 kips/ft including its own self weight plus a uniform service (unfactored) live load of 1.2 kips/ft. The concrete is normal-weight concrete. The beam is reinforced with 3 No. 8 bars. The concrete strength is 6,400 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.      

Reinforced concrete members usually crack under service loads.

A rectangular beam has a cross section of b = 14 in., h = 30 in., and d = 27.5 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.

The major strength limit states in reinforced concrete are caused by excessive deflections, excessive crack widths, and undesirable vibrations.