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A beam has dimensions of b = 18 in., h = 24 in., and d = 21.5 in. and is reinforced with 3 No. 6 bars. The concrete strength is 7,900 psi, and the yield strength of the reinforcement is 60,000 psi. Assuming the reinforcement has yielded, determine the depth to the neutral axis, c.

Which symbol represents the specified yield strength of steel reinforcement?

A beam has dimensions of b = 16 in., h = 24 in., and d = 21.5 in. and is reinforced with 2 No. 6 bars. The concrete strength is 9,100 psi, and the yield strength of the reinforcement is 60,000 psi. Determine the strength Mn for this beam.

It is important to overestimate d, because normal construction practices may lead to smaller values of d than are shown on the drawings.

What is the symbol for nominal flexural strength?

A beam has dimensions of b = 18 in., h = 22 in., and d = 19.5 in. and is reinforced with 3 No. 8 bars. The concrete strength is 4,600 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the compressive stress block is a = 2.02046 in. and the strain in the reinforcement is εs = 0.020742, determine the strength φMn for this beam. Assume the transverse reinforcement is not spirals.

A beam has dimensions of b = 14 in., h = 30 in., d’ = 2.5 in., and d = 27.5 in. It is reinforced with 2 No. 5 bars on the compression side and 4 No. 8 bars on the tension side. The concrete strength is 2,500 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the neutral axis is c = 6.268 in., determine the strain in the compression reinforcement, ε’s.

Simply supported beams loaded with only gravity loads require longitudinal reinforcement along the bottom of the beam.

One of the four primary reasons for using compression reinforcement in beams is increased ductility.

A simply supported beam with dimensions of b = 10 in., h = 24 in., d = 21.5 in., and L = 20 ft supports a uniform service (unfactored) dead load consisting of its own weight plus 1.2 kips/ft and a uniform service (unfactored) live load of 1.0 kips/ft. The concrete is normal-weight concrete. Determine the moment due to the factored loads, Mu.