Compute φVn for the cross section shown. Assume f’c = 3,000 psi, fyt = 40,000 psi, d = 24 in., w = 18.5 in., t = 4 in., and that there are four No. 9 longitudinal tension bars and No. 4 stirrups at 8 in. o.c.

A beam has dimensions of b = 14 in., h = 26 in., d’ = 2.5 in., and d = 23.5 in. It is reinforced with 2 No. 5 bars on the compression side and 4 No. 8 bars on the tension side. The concrete strength is 2,800 psi, and the yield strength of the reinforcement is 60,000 psi. For the results given below, determine the strength Mn for this beam.a = 4.828 in. (depth of concrete stress block)Cc = 159.4 kips (compressive force in concrete)Cs = 30.2 kips (compressive force in steel)T = 189.6 kips (tensile force in steel)

If a designer wants to increase the moment capacity of a beam, he/she could reduce the amount of tension reinforcement and add compression reinforcement to keep the section compression-controlled.

Compute φVn for the cross section shown. Assume f’c = 7,500 psi, fyt = 40,000 psi, b = 12 in., d = 25 in., and that there are four No. 8 longitudinal tension bars and No. 3 stirrups at 9 in. o.c.

In a singly-reinforced concrete beam, the compressive load C can be calculated by _______.

The determination of whether a reinforced concrete floor system is classified as a one-way or two-way system is based on the ratio of the span lengths for the floor slab in the two principal horizontal directions.

If φVc = 66 kip and Vu = 26 kip, are stirrups required?

What causes vertical cracks to occur first?

Compute φVn for the cross section shown. Assume f’c = 4,000 psi, fyt = 60,000 psi, b = 10 in., d = 26 in., and that there are four No. 7 longitudinal tension bars and No. 4 stirrups at 8 in. o.c.

For a beam with stirrup hooks, the free end of the bar must extend at least _____ from the hook. Assume b = 15 in., d = 29 in., and that there are four No. 6 longitudinal tension bars and No. 5 stirrups at 8 in. o.c. The stirrup hooks are 135°.