One of the three basic assumptions in the theory of flexure for reinforce concrete is that sections perpendicular to the axis of bending that are plane before bending remains plane after bending.

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 7,000 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the compressive stress block is a = 0.554622 in. and the strain in the reinforcement is εs = 0.078407, 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 5 No. 8 bars on the tension side. The concrete strength is 3,100 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the neutral axis is c = 6.547 in., determine the strain in the compression reinforcement, ε’s.

A beam is singly reinforced with the reinforcement in two rows. The bottom row contains 8 No. 7 bars at a depth of 18 in. The top row contains 5 No. 7 bars at a depth of 13 in. Determine the effective (centroidal) depth, d, of the steel.

Of the following foods, which would most likely have no protein in it? 

A beam has dimensions of b = 14 in., h = 30 in., and d = 27.5 in. and is reinforced with 5 No. 5 bars. The concrete strength is 6,100 psi, and the yield strength of the reinforcement is 60,000 psi. Determine the nominal moment capacity, Mn, of the beam.

(06.06 MC)  Monthly grocery cost based on the average number of shopping trips is predicted using the least-square regression line, ŷ = 275.3 + 90.7x, where ŷ represents the predicted monthly expense and x represents the average number of trips. A shopper visits the grocery store an average of 3.2 times and has a monthly cost of $520. What is the residual for the shopper? (3 points)

A beam has dimensions of b = 16 in., h = 26 in., and d = 23.5 in. and is reinforced with 4 No. 8 bars. The concrete strength is 8,200 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.

(04.02 MC)  The probability of tails of a weighted coin is 0.65. The number of tails is noted each of the 15 times the coin is tossed. If this procedure is repeated 100 times, what type of distribution is simulated? (3 points)

A beam has dimensions of b = 16 in., h = 28 in., and d = 25.5 in. and is reinforced with 3 No. 8 bars. The concrete strength is 6,400 psi, and the yield strength of the reinforcement is 60,000 psi. Determine the strength Mn for this beam.