3. (20 points) A concrete floor system consists of parallel T beams spaced 10 feet on center (see sketch below)and span 32 feet between center points of columns. L-beams are

used at the edges of the slabs. The 6 inch thick slab was poured monolithically with the beams that have a web width of 14 inches and a total depth (measured from the top of the slab to the bottom of the web) of 28 inches. Assume the effective depth "d" to be H - 3inches. In addition to it's own weight, each beam must carry an unfactored superimposed dead load of 50pounds per square foot and a live load of 225 pounds per square foot. The concrete compressive strength is 3ksi and the yield strength of steel is 60 ksi. Calculate As for the T-beams and the edge L-beams, select bars and check spacing, minimum steel requirements, equilibrium and if tension control.

Fig: 1

Fig: 2