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A rectangular beam has a cross section of b = 14 in., h = 24 in., and d = 21.5 in. It is reinforced with four No. 5 Grade 60 bars. The concrete strength is 8,500 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the gross moment of inertia, Ig, for the beam.

A wall footing has the following conditions. Determine the distance to the neutral axis, c, measured from the top of the footing. Assume the footing is 4 ft wide, the pressure that acts on the bottom of the footing is 6,100 psf, and the reinforcement is a #5 bar spaced every 12 inches.The bottom of the footing is at a depth of 3 ft below grade.The service dead load is 11 kips/ft, and the service live load is 7 kips/ft.The wall is 12 in. thick.The footing is 16 in. thick.The allowable soil pressure, qa, is 5,200 psf.The soil has a density of 110 lb/ft3.The concrete has a density of 150 lb/ft3.The concrete cover has a thickness of 3 in.f’c = 3,800 psi and fy = 60,000 psi.

A beam is singly reinforced with the reinforcement in two rows. The bottom row contains 6 No. 6 bars at a depth of 20 in. The top row contains 4 No. 5 bars at a depth of 17 in. Determine the effective (centroidal) depth, d, of the steel.

A beam is singly reinforced with the reinforcement in two rows. The bottom row contains 10 No. 6 bars at a depth of 14 in. The top row contains 8 No. 7 bars at a depth of 10 in. Determine the effective (centroidal) depth, d, of the steel.

Compute the maximum bar spacing, s, to control for cracks in a one-way slab with 1.8 in. of clear cover and f​y​ = 68 ksi.

A simply supported beam with dimensions of b = 18 in., h = 30 in., d = 27.5 in., and L = 24 ft supports a uniform service (unfactored) dead load of 2.1625 kips/ft including its own self weight plus a uniform service (unfactored) live load of 0.9 kips/ft. The beam is reinforced with two 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 = 144.2 kip-ft, and the maximum applied bending moment due to the combined service loads (dead plus live) Ma = 220.5 kip-ft. The neutral axis location of the cracked beam (measured from the top of the beam) is 3.7209 in.

A rectangular beam has a cross section of b = 18 in., h = 24 in., and d = 21.5 in. It is reinforced with five No. 6 Grade 60 bars. The concrete strength is 6,700 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the modulus of rupture of the concrete, fr.

A rectangular beam has a cross section of b = 16 in., h = 30 in., and d = 27.5 in. It is reinforced with two No. 5 Grade 60 bars. The concrete strength is 4,000 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the cracking moment, Mcr.

A rectangular beam has a cross section of b = 16 in., h = 22 in., and d = 19.5 in. It is reinforced with five No. 7 Grade 60 bars. The concrete strength is 6,700 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).

A wall footing has the following conditions. Determine the required cross-sectional area of shrinkage and temperature reinforcement. Assume the footing is 4 ft wide, the pressure that acts on the bottom of the footing is 6,200 psf, and the reinforcement is a #6 bar spaced every 12 inches.The bottom of the footing is at a depth of 3 ft below grade.The service dead load is 10 kips/ft, and the service live load is 8 kips/ft.The wall is 12 in. thick.The footing is 16 in. thick.The allowable soil pressure, qa, is 5,000 psf.The soil has a density of 110 lb/ft3.The concrete has a density of 150 lb/ft3.The concrete cover has a thickness of 3 in.f’c = 3,300 psi and fy = 60,000 psi.