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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.

In analysis, there is one unique answer. One determines the beam strength given several factors such as concrete strength, cross section, reinforcement size, location, and yield strength.

Assuming Vs does not exceed 4sqrt(f’c)bwd, the maximum spacing for vertical stirrups in the following beam is _____. Let d = 57 in., w = 47.5 in., and t = 6 in. There are five No. 8 longitudinal tension bars and No. 4 stirrups at 12 in. o.c.

A beam has dimensions of b = 16 in., h = 28 in., and d = 25.5 in. and is reinforced with 2 No. 8 bars. The concrete strength is 5,200 psi, and the yield strength of the reinforcement is 60,000 psi. Determine the strength Mn for this beam.

What causes vertical cracks to occur first?

For a beam with stirrup hooks, the free end of the bar must extend at least _____ from the hook. Assume b1 = 39 in., b2 = 11 in., d1 = 4 in., d2 = 23 in., and that there are three No. 7 longitudinal tension bars and No. 4 stirrups at 6 in. o.c. The stirrup hooks are 90°.

Flexural tension cracking will occur when the stress in the extreme tension fiber equals the modulus of rupture.

A 115-mm-long beam supports a load of P = 30 N at midspan. The cross section is rectangular with width b = 26 mm and height h = 55 mm. Determine the magnitude of the horizontal shear stress at the centroid of the cross section.

Assuming Vs exceeds 4sqrt(f’c)bwd, the maximum spacing for vertical stirrups in the following beam is _____. Let b1 = 30 in., b2 = 10 in., d = 59 in., h1 = 6 in., h2 = 49 in., h3 = 9 in., and t = 8 in. There are sixNo. 8 longitudinal tension bars and No. 4 stirrups at 12 in. o.c.

Generally, No. 4 and smaller bars are used for flexural reinforcement in slabs, because larger wires tend to be bent out of position by workers walking on the reinforcement during construction.