In seismic regions, column ties are heavier and much more closely spaced than ties in nonseismic regions.

A wall footing has the following conditions. Determine the minimum width of the footing.The bottom of the footing is at a depth of 3 ft below grade.The service dead load is 13 kips/ft, and the service live load is 7 kips/ft.The wall is 14 in. thick.The footing is 16 in. thick.The allowable soil pressure, qa, is 6,000 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 = 3,900 psi and fy = 60,000 psi.

A wall footing has the following conditions. Determine the minimum cross-sectional area of the reinforcement. Assume the footing is 6 ft wide and the pressure that acts on the bottom of the footing is 4,200 psf.The bottom of the footing is at a depth of 3 ft below grade.The service dead load is 13 kips/ft, and the service live load is 6 kips/ft.The wall is 16 in. thick.The footing is 14 in. thick.The allowable soil pressure, qa, is 4,100 psf.The soil has a density of 125 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 9.7 kips/ft, and the service live load is 6.6 kips/ft.The wall is 16 in. thick.The footing is 12 in. thick.The allowable soil pressure, qa, is 5,100 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 = 3,500 psi and fy = 60,000 psi.

What is the strength-reduction factor, φ, for spiral columns?

A wall footing has the following conditions. Determine the pressure that acts on the bottom of the footing. Assume the footing is 4 ft wide.The bottom of the footing is at a depth of 4 ft below grade.The service dead load is 11.2 kips/ft, and the service live load is 6.8 kips/ft.The wall is 10 in. thick.The footing is 16 in. thick.The allowable soil pressure, qa, is 5,600 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 = 3,500 psi and fy = 60,000 psi.

A wall footing has the following conditions. Determine the minimum cross-sectional area of the reinforcement. Assume the footing is 5 ft wide and the pressure that acts on the bottom of the footing is 6,160 psf.The bottom of the footing is at a depth of 2 ft below grade.The service dead load is 15 kips/ft, and the service live load is 8 kips/ft.The wall is 14 in. thick.The footing is 16 in. thick.The allowable soil pressure, qa, is 4,900 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 = 3,000 psi and fy = 60,000 psi.

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 5,000 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 6 kips/ft, and the service live load is 8 kips/ft.The wall is 12 in. thick.The footing is 14 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 = 3,000 psi and fy = 60,000 psi.

A point outside an interaction diagram represents a combination of P and M that will not cause failure.

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 = 22 in.Column thickness, h = 20 in.Clear cover to ties = 1.5 in.Number of longitudinal bars = 10Size of longitudinal bars = No. 9Size of ties = No. 3Concrete strength = 6,000 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 40,000 psi