For a beam with stirrup hooks, the free end of the bar must extend at least _____ from the hook. Assume b = 14 in., d = 28 in., and that there are four No. 9 longitudinal tension bars and No. 4 stirrups at 7 in. o.c. The stirrup hooks are 135°.

Researchers studying reinforced concrete have considered a mechanical explanation of Vc to be the Holy Grail.

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

The use of compression reinforcement permits the use of more tension reinforcement to increase the strength of a given beam section while keeping the section tension-controlled.

Determine the transverse reinforcement index, Ktr, for a rectangular beam with b = 17 in. and d = 24 in., three uncoated No. 8 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 3 Grade 40 stirrups located every 6 in. along the span. Assume 4,000-psi normal-weight concrete and a clear cover of 1.75 in.

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, d = 23 in., w = 13.5 in., and t = 6 in. There are five No. 7 longitudinal tension bars and No. 5 stirrups at 6 in. o.c.

When a reinforcing bar is loaded in _______, the diameter of the bar decreases slightly, due to Poisson’s ratio.

If φVc = 34 kip and Vu = 68 kip, are stirrups required?

The shear failure of a slender beam without stirrups is sudden and dramatic.

A concrete floor system with a ratio of the longer to the shorter span length that is less than 2 is usually considered a two-way system.