A concrete cube is subjected to biaxial loading. Estimate the compressive strength σ1 if σ2 = 0.8 times the tensile strength, in tension.

Prolonged moist curing leads to the lowest concrete strength.

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 2 ft below grade.The service dead load is 9.7 kips/ft, and the service live load is 6.9 kips/ft.The wall is 12 in. thick.The footing is 12 in. thick.The allowable soil pressure, qa, is 4,900 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 = 3,200 psi and fy = 60,000 psi.

The increase in the volume of concrete during hardening and drying under constant temperature is called shrinkage.

Although concrete is made up of essentially elastic, brittle materials, its stress-strain curve is nonlinear.

Which symbol is used to represent concrete’s compressive strength?

The specified compressive strength, fc’, is _______ the average strength?

High strength concrete usually has a higher paste content.

A concrete cube is subjected to biaxial loading. Estimate the compressive strength σ2 if σ1 = 0.5 times the tensile strength, in tension.

Prolonged moist curing leads to the highest concrete strength.