A rectangular beam has a cross section of b = 16 in., h = 28 in., and d = 25.5 in. It is reinforced with three No. 7 Grade 60 bars. The concrete strength is 4,300 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the gross moment of inertia, Ig, for the beam.

Determine the transverse reinforcement index, Ktr, for a rectangular beam with b = 18 in. and d = 23 in., three galvanized No. 8 Grade 60 tension-reinforcement bars placed in the top of the beam, and No. 3 Grade 60 stirrups located every 8 in. along the span. Assume 8,000-psi normal-weight concrete and a clear cover of 2 in.

The hardest way to test the bond strength of bars in a laboratory is by the pull-out test.

Concrete cover may be decreased to increase a member’s fire resistance.

A bar will pull out of concrete if the distance from a point where the stress is equal to fy to the end of the bar is greater than the developmental length.

In deformed reinforcing bars, adhesion and lateral friction are insignificant sources of bond strength.

Compute the maximum bar spacing, s, to control for cracks in a one-way slab with 2.2 in. of clear cover and f​y​ = 62 ksi.

There are universally accepted rules for maximum crack widths.

A rectangular beam has a cross section of b = 18 in., h = 24 in., and d = 21.5 in. It is reinforced with two No. 8 Grade 60 bars. The concrete strength is 8,200 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the cracking moment, Mcr.

A rectangular beam has a cross section of b = 14 in., h = 22 in., and d = 19.5 in. It is reinforced with five No. 5 Grade 60 bars. The concrete strength is 9,100 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the transformed cross-sectional area of the bars, Ast.