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The strength-reduction factor is multiplied by the factored design moment to account for possible variations in dimensions and material strengths and possible inaccuracies in the strength equations.

A beam has dimensions of b = 14 in., h = 26 in., d’ = 2.5 in., and d = 23.5 in. It is reinforced with 2 No. 5 bars on the compression side and 5 No. 8 bars on the tension side. The concrete strength is 3,700 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the neutral axis is c = 5.588 in., determine the force in the compression reinforcement, Cs.

A classmate has suggested a beam design that has dimensions of b = 16 in., h = 24 in., and d = 21.5 in. and is reinforced with 4 No. 14 bars. Assuming a cover of 1.5 in. and a stirrup diameter of 0.5 in., does the reinforcement fit within a single row as suggested?

You are considering a beam design that has dimensions of b = 16 in., h = 22 in., and d = 19.5 in. The beam is singly reinforced with all of the reinforcement in a single row. The concrete strength is 2,500 psi, and the yield strength of the reinforcement is 60,000 psi. What cross-sectional area of reinforcement is needed to achieve a strain in the reinforcement of 0.0075?

A simply supported beam with dimensions of b = 16 in., h = 30 in., d = 27.5 in., and L = 17 ft supports a uniform service (unfactored) dead load consisting of its own weight plus 1.1 kips/ft and a uniform service (unfactored) live load of 1.1 kips/ft. The concrete is normal-weight concrete. Determine the moment due to the factored loads, Mu.      

A beam is singly reinforced with the reinforcement in two rows. The bottom row contains 8 No. 6 bars at a depth of 18 in. The top row contains 6 No. 7 bars at a depth of 14 in. Determine the effective (centroidal) depth, d, of the steel.

According to the theory of flexure for reinforced concrete, the strain in the reinforcement is _______ the strain in the concrete at the same level.

The elastic beam theory is used in the design of reinforced concrete beams.

A tension-controlled section has a tension-reinforcement area such that when the beam reaches its nominal flexural strength, the net tensile strain in the extreme layer of tensile steel is greater than or equal to 0.005.

Cantilever beams loaded with only gravity loads develop positive bending moments throughout the span.