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Simply supported beams loaded with only gravity loads develop tension cracks along the bottom of the beam.

The textbook author recommends using As’ ≤ 0.5As in doubly reinforced beam sections.

The thickness of concrete cover should be decreased for highly corrosive environments.

A beam has dimensions of b = 14 in., h = 28 in., and d = 25.5 in. and is reinforced with 2 No. 6 bars. The concrete strength is 3,700 psi, and the yield strength of the reinforcement is 60,000 psi. Assuming the reinforcement has yielded, determine the tensile force T in the reinforcement.

If a beam is supported by a girder of essentially the same depth, the compression fans that form in the supporting girder tend to tie the beam and girder together.

If a designer wants to reduce the size and weight of a beam, he/she could use additional tension reinforcement and add compression reinforcement to keep the section tension-controlled.

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.

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.

At a point subjected to plane stress, the stresses are σx = 50 MPa, σy = –90 MPa, and τxy = 70 MPa. Determine the angle θp corresponding to the orientation of the principal planes at the point.

A concrete floor system with a ratio of the longer to the shorter span length that is greater than or equal to 2 is usually considered a one-way system.