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Determine the casting-position modification factor, ψt, for a rectangular beam with b = 18 in. and d = 21 in., five uncoated No. 6 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 3 Grade 60 stirrups located every 8 in. along the span. Assume 8,000-psi lightweight concrete and a clear cover of 2 in.

Assuming Vs does not exceed 4sqrt(f’c)bwd, the maximum spacing for vertical stirrups in the following beam is _____. Let d = 47 in., w = 37.5 in., and t = 6 in. There are five No. 8 longitudinal tension bars and No. 3 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 b1 = 35 in., b2 = 15 in., d1 = 6 in., d2 = 27 in., and that there are three No. 6 longitudinal tension bars and No. 4 stirrups at 9 in. o.c. The stirrup hooks are 90°.

Mis hermanos van a [q10] al fútbol americano.

A simply-supported beam has a 5 kip/ft uniformly-distributed load over the entire 12-ft span. What is the magnitude of the maximum shear force in the beam?

Compute φVn for the cross section shown. Assume f’c = 3,500 psi, fyt = 40,000 psi, b1 = 24 in., b2 = 12 in., d = 28 in., h1 = 5 in., h2 = 19 in., h3 = 9 in., t = 8 in., and that there are six No. 8 longitudinal tension bars and No. 3 stirrups at 9 in. o.c.

Actual bond stresses remain constant between cracks.

In regards to shear cracks, larger aggregate _______.

Use ACI 318-14 Table 25.4.2.2 to determine the development length for the straight tension bars (no hooks) in a rectangular beam with b = 17 in. and d = 22 in., three uncoated No. 7 Grade 60 bars placed in the top of the beam, and No. 3 Grade 60 stirrups located every 10 in. along the span. Assume 6,000-psi lightweight concrete and a clear cover of 2 in.

Which symbol represents the lightweight-concrete-aggregate factor?