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Bars of longitudinal reinforcement often do not have to extend the full length of a beam.

A beam has dimensions of b = 14 in., h = 28 in., d’ = 2.5 in., and d = 25.5 in. It is reinforced with 2 No. 5 bars on the compression side and 5 No. 8 bars on the tension side. The concrete strength is 4,000 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the neutral axis is c = 5.216 in., determine the strain in the compression reinforcement, ε’s.

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 vertical directions.

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 2,500 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the neutral axis is c = 6.268 in., determine the strain in the compression reinforcement, ε’s.

Where there are several layers of reinforcement, a continuous vertical opening large enough for the concrete vibrator to pass through should be provided.

In high-strength concrete, cracks tend to go around pieces of the aggregate rather than penetrating them.

For a beam with stirrup hooks, the free end of the bar must extend at least _____ from the hook. Assume b = 12 in., d = 23 in., and that there are four No. 6 longitudinal tension bars and No. 5 stirrups at 12 in. o.c. The stirrup hooks are 135°.

A beam has dimensions of b = 14 in., h = 30 in., d’ = 2.5 in., and d = 27.5 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)

A continuous beam’s flexural reinforcement must extend at least _____ from the point where it is no longer needed to resist tension. Assume f’c = 4,000 psi, fyt = 40,000 psi, b1 = 29 in., b2 = 14 in., d1 = 4 in., d2 = 15 in., and that there are three No. 9 longitudinal tension bars and No. 3 stirrups at 11 in. o.c. The stirrup hooks are 90°.

Shrinkage cracks perpendicular to the span of the one-way design strips will be crossed by flexural reinforcement, which will limit the width of the cracks.