The determination of whether a reinforced concrete floor system is classified as a one-way or two-way system is based on the ratio of the span lengths for the floor slab in the two principal vertical directions.

In two-way floor systems, there is a relatively short span length in one horizontal direction compared to the span length in the perpendicular direction.

The largest moments in a continuous beam or a frame occur when some spans are loaded with live load and others are not. Influence lines are often used to determine which span should and should not be loaded.

A classmate has suggested a beam design that has dimensions of b = 14 in., h = 24 in., and d = 21.5 in. and is reinforced with 4 No. 9 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?

A beam has dimensions of b = 18 in., h = 12 in., and d = 9.5 in. and is reinforced with 5 No. 8 bars. The concrete strength is 3,500 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the neutral axis is c = 5.207 in., does the reinforcement yield?

Determine As,min for the following beam given that f’c = 7,750 psi and fy = 60,000 psi.

A beam is singly reinforced with the reinforcement in two rows. The bottom row contains 9 No. 6 bars at a depth of 22 in. The top row contains 5 No. 8 bars at a depth of 17.5 in. Determine the effective (centroidal) depth, d, of the steel.

A beam has dimensions of b = 14 in., h = 26 in., and d = 23.5 in. and is reinforced with 3 No. 8 bars. The concrete strength is 9,100 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.

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 2,500 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the neutral axis is c = 7.961 in., determine the force in the compression reinforcement, Cs.

Alternate span loading is the common loading pattern for determining maximum negative moments at supports due to live load.