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If φVc = 77 kip and Vu = 37 kip, are stirrups required?

Compute φVn for the cross section shown. Assume f’c = 6,000 psi, fyt = 60,000 psi, b1 = 31 in., b2 = 10 in., d1 = 5 in., d2 = 15 in., and that there are three No. 9 longitudinal tension bars and No. 3 stirrups at 7 in. o.c.

If the beam is supported by a girder of the same _______, the compression fans that form in the supported beam will tend to push the bottom off the supporting beam.

Compute φVn for the cross section shown. Assume f’c = 3,000 psi, fyt = 40,000 psi, d = 29 in., w = 19.5 in., t = 6 in., and that there are four No. 8 longitudinal tension bars and No. 5 stirrups at 6 in. o.c.

A classmate has suggested a beam design that has dimensions of b = 12 in., h = 30 in., and d = 27.5 in. and is reinforced with 4 No. 11 bars. Assuming a cover of 1.5 in. and a stirrup diameter of 0.5 in., does the reinforcement fit within a single row as suggested?

A beam has dimensions of b = 20 in., h = 10 in., and d = 7.5 in. and is reinforced with 4 No. 9 bars. The concrete strength is 4,700 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the neutral axis is c = 3.686 in., does the reinforcement yield?

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 = 27 in., b2 = 11 in., d1 = 6 in., d2 = 17 in., and that there are three No. 6 longitudinal tension bars and No. 3 stirrups at 7 in. o.c. The stirrup hooks are 90°.

It is rare to design beams where the b and h values are already known.

For a beam with stirrup hooks, the free end of the bar must extend at least _____ from the hook. Assume b1 = 39 in., b2 = 15 in., d1 = 8 in., d2 = 19 in., and that there are three No. 6 longitudinal tension bars and No. 3 stirrups at 12 in. o.c. The stirrup hooks are 90°.

For a beam with stirrup hooks, the free end of the bar must extend at least _____ from the hook. Assume b = 16 in., d = 28 in., and that there are four No. 8 longitudinal tension bars and No. 4 stirrups at 12 in. o.c. The stirrup hooks are 135°.