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Use the interaction diagrams found in Appendix A of the textbook to determine whether the following circular spiral column can safely support a load of Pu = 704 kip and Mu = 241.3 kip-ft.h = 16 in.fc’ = 4 ksify = 60 ksiγ = 0.9ρg = 0.02

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 = 26 in.Column thickness, h = 28 in.Clear cover to ties = 1.5 in.Number of longitudinal bars = 12Size of longitudinal bars = No. 10Size of ties = No. 4Concrete strength = 4,500 psiYield strength of longitudinal bars = 60,000 psiYield strength of ties = 40,000 psi

A wall footing has the following conditions. Determine the shear capacity, φVn, of the footing. Assume the footing is 4 ft wide, the pressure that acts on the bottom of the footing is 5,200 psf, and the reinforcement is a #5 bar spaced every 12 inches.The bottom of the footing is at a depth of 2 ft below grade.The service dead load is 8 kips/ft, and the service live load is 7 kips/ft.The wall is 16 in. thick.The footing is 12 in. thick.The allowable soil pressure, qa, is 4,400 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 = 3,400 psi and fy = 60,000 psi.

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 5,200 psf.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 7 kips/ft.The wall is 16 in. thick.The footing is 15 in. thick.The allowable soil pressure, qa, is 4,800 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 = 3,600 psi and fy = 60,000 psi.

A wall footing has the following conditions. Determine the depth, d, of the reinforcement. Assume the footing is 4 ft wide, the pressure that acts on the bottom of the footing is 6,000 psf, and the reinforcement is a #8 bar spaced every 12 inches.The bottom of the footing is at a depth of 3 ft below grade.The service dead load is 12 kips/ft, and the service live load is 6 kips/ft.The wall is 16 in. thick.The footing is 12 in. thick.The allowable soil pressure, qa, is 5,400 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.

It is unusual for columns to support axial forces and bending about two perpendicular axes.

The minimum number of longitudinal bars in a circular column is six.

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 wall footing has the following conditions. Determine the critical bending moment, Mu, at the face of the wall. Assume the footing is 5 ft wide and the pressure that acts on the bottom of the footing is 4,640 psf.The bottom of the footing is at a depth of 2 ft below grade.The service dead load is 10 kips/ft, and the service live load is 7 kips/ft.The wall is 16 in. thick.The footing is 15 in. thick.The allowable soil pressure, qa, is 4,200 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.

Columns with only two layers of steel and a high steel ratio typically have interaction diagrams composed of relatively straight lines.