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A wall footing has the following conditions. Determine the critical bending moment, Mu, at the face of the wall. Assume the footing is 4 ft wide and the pressure that acts on the bottom of the footing is 6,600 psf.The bottom of the footing is at a depth of 3 ft below grade.The service dead load is 14 kips/ft, and the service live load is 6 kips/ft.The wall is 10 in. thick.The footing is 14 in. thick.The allowable soil pressure, qa, is 6,000 psf.The soil has a density of 130 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 wall footing has the following conditions. Determine how much greater the factored load is than the unfactored load.The bottom of the footing is at a depth of 2 ft below grade.The service dead load is 7.5 kips/ft, and the service live load is 7 kips/ft.The wall is 10 in. thick.The footing is 15 in. thick.The allowable soil pressure, qa, is 4,900 psf.The soil has a density of 120 lb/ft3.The concrete has a density of 150 lb/ft3.The concrete cover has a thickness of 3 in.f’c = 3,100 psi and fy = 60,000 psi.

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 6 ft wide, the pressure that acts on the bottom of the footing is 5,133 psf, and the reinforcement is a #9 bar spaced every 12 inches.The bottom of the footing is at a depth of 5 ft below grade.The service dead load is 15 kips/ft, and the service live load is 8 kips/ft.The wall is 10 in. thick.The footing is 12 in. thick.The allowable soil pressure, qa, is 5,000 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 = 3,500 psi and fy = 60,000 psi.

Determine the maximum pitch, s, for the spirals in the following circular column.Column diameter, h = 20 in.Clear cover to spirals = 1.5 in.Number of longitudinal bars = 18Size of longitudinal bars = No. 10Size of spiral = No. 3Concrete strength = 8,500 psiYield strength of longitudinal bars = 60,000 psiYield strength of spiral = 60,000 psi

A wall footing has the following conditions. Determine the pressure that acts on the soil. Assume the footing is 3 ft wide.The bottom of the footing is at a depth of 5 ft below grade.The service dead load is 6 kips/ft, and the service live load is 6 kips/ft.The wall is 14 in. thick.The footing is 12 in. thick.The allowable soil pressure, qa, is 5,400 psf.The soil has a density of 130 lb/ft3.The concrete has a density of 150 lb/ft3.The concrete cover has a thickness of 3 in.f’c = 3,000 psi and fy = 60,000 psi.

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 3 ft wide, the pressure that acts on the bottom of the footing is 7,066 psf, and the reinforcement is a #9 bar spaced every 12 inches.The bottom of the footing is at a depth of 4 ft below grade.The service dead load is 7 kips/ft, and the service live load is 8 kips/ft.The wall is 12 in. thick.The footing is 11 in. thick.The allowable soil pressure, qa, is 6,000 psf.The soil has a density of 130 lb/ft3.The concrete has a density of 150 lb/ft3.The concrete cover has a thickness of 3 in.f’c = 3,600 psi and fy = 60,000 psi.

Compute the axial compressive strength Pn and moment capacity Mn of the following tied column when the largest strain in the concrete is 0.003 and the strain in the tension reinforcement is 0.003. Note that you should not include φ in the answer and that you should not consider Pn,max.b = 14 in.h = 20 in.Clear cover to ties = 1.5 in.Number of longitudinal bars = 6Size of longitudinal bars = No. 8Size of ties = No. 4Concrete strength = 5,000 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 60,000 psi

Determine the required splice length for the longitudinal bars in the following tied column. Assume that all of the longitudinal bars are in compression and that you will use a contact lap splice. Do not incorporate a reduction in length due to ACI 318-14 Section 10.7.5.2.1.Column width, b = 20 in.Column thickness, h = 26 in.Clear cover to ties = 1.5 in.Number of longitudinal bars = 10Size of longitudinal bars = No. 7Size of ties = No. 3Concrete strength = 3,000 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 40,000 psi

Determine the maximum axial strength φPn,max for the following circular tie column.Column diameter, h = 22 in.Number of longitudinal bars = 15Size of longitudinal bars = No. 8Size of ties = No. 3Concrete strength = 5,000 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 60,000 psi

A wall footing has the following conditions. Determine the depth, d, of the reinforcement. Assume the footing is 3 ft wide, the pressure that acts on the bottom of the footing is 6,400 psf, and the reinforcement is a #7 bar spaced every 12 inches.The bottom of the footing is at a depth of 3 ft below grade.The service dead load is 8 kips/ft, and the service live load is 6 kips/ft.The wall is 12 in. thick.The footing is 14 in. thick.The allowable soil pressure, qa, is 5,700 psf.The soil has a density of 120 lb/ft3.The concrete has a density of 150 lb/ft3.The concrete cover has a thickness of 3 in.f’c = 3,100 psi and fy = 60,000 psi.