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A wall footing has the following conditions. Determine the critical one-way shear, Vu, at a distance of d from the face of the wall. Assume the footing is 6 ft wide, the pressure that acts on the bottom of the footing is 4,733 psf, and the reinforcement is a #8 bar spaced every 12 inches.The bottom of the footing is at a depth of 2 ft below grade.The service dead load is 13 kips/ft, and the service live load is 8 kips/ft.The wall is 16 in. thick.The footing is 10 in. thick.The allowable soil pressure, qa, is 4,000 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 = 3,500 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 3 ft wide and the pressure that acts on the bottom of the footing is 6,133 psf.The bottom of the footing is at a depth of 2 ft below grade.The service dead load is 6 kips/ft, and the service live load is 7 kips/ft.The wall is 16 in. thick.The footing is 11 in. thick.The allowable soil pressure, qa, is 4,700 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 = 3,000 psi and fy = 60,000 psi.

Strength of concrete tends to decrease as the maximum aggregate size decreases.

Subfreezing temperatures can significantly decrease the compressive and tensile strengths and the modulus of elasticity of moist concrete.

The strength of concrete under biaxial compression is less than the uniaxial compressive strength.

Drying shrinkage occurs in carbon-dioxide rich atmospheres.

A wall footing has the following conditions. Determine the moment capacity, Mn, of the footing. Assume the footing is 3 ft wide, the pressure that acts on the bottom of the footing is 6,533 psf, and the reinforcement is a #5 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 7 kips/ft.The wall is 10 in. thick.The footing is 16 in. thick.The allowable soil pressure, qa, is 5,700 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.

In fcr = f’c + 2.33s – 500, what does the s represent?

Although concrete is made up of essentially elastic, brittle materials, its stress-strain curve is nonlinear and it appears to be somewhat _______.

There is a permanent reduction in strength when concrete is exposed to sustained high loads.