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Compute the maximum bar spacing, s, to control for cracks in a one-way slab with 1.9 in. of clear cover and f​y​ = 60 ksi.

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 7,300 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the modulus of rupture of the concrete, fr.

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 5,900 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 9 kips/ft, and the service live load is 8 kips/ft.The wall is 12 in. thick.The footing is 15 in. thick.The allowable soil pressure, qa, is 5,600 psf.The soil has a density of 115 lb/ft3.The concrete has a density of 150 lb/ft3.The concrete cover has a thickness of 3 in.f’c = 3,700 psi and fy = 60,000 psi.

A rectangular beam has a cross section of b = 18 in., h = 26 in., and d = 23.5 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 cracked moment of inertia, Icr. The neutral axis location of the cracked beam (measured from the top of the beam) is 6.0183 in.

A simply supported beam with dimensions of b = 14 in., h = 22 in., d = 19.5 in., and L = 25 ft supports a uniform service (unfactored) dead load of 2.020833 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 4 No. 6 bars. The concrete strength is 4,300 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 simply supported beam with dimensions of b = 14 in., h = 22 in., d = 19.5 in., and L = 22 ft supports a uniform service (unfactored) dead load of 1.320833 kips/ft including its own self weight plus a uniform service (unfactored) live load of 1.3 kips/ft. The beam is reinforced with four No. 7 Grade 60 bars. The concrete strength is 9,400 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Using the effective moment of inertia, determine the immediate mid-span deflection of the beam due to the combined service loads (dead plus live).The effective moment of inertia Ie = 3,969.5 in.4.

A rectangular beam has a cross section of b = 18 in., h = 26 in., and d = 23.5 in. It is reinforced with two No. 6 Grade 60 bars. The concrete strength is 8,200 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the modulus of rupture of the concrete, fr.

A simply supported beam with dimensions of b = 18 in., h = 30 in., d = 27.5 in., and L = 16 ft supports a uniform service (unfactored) dead load of 1.6625 kips/ft including its own self weight plus a uniform service (unfactored) live load of 0.8 kips/ft. The beam is reinforced with five No. 7 Grade 60 bars. The concrete strength is 3,700 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the effective moment of inertia, Ie.The cracked moment Mcr = 102.6 kip-ft, and the maximum applied bending moment due to the combined service loads (dead plus live) Ma = 78.8 kip-ft. The neutral axis location of the cracked beam (measured from the top of the beam) is 7.4725 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. 8 Grade 60 bars. The concrete strength is 5,500 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 = 14 in., h = 28 in., d = 25.5 in., and L = 20 ft supports a uniform service (unfactored) dead load of 2.108333 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 5 No. 8 bars. The concrete strength is 7,300 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.