DanHalen
Well-known member
First let me state that I'm using the All-In-One Civil Engineering PE Breadth & Depth Exam Guide, 2nd Ed. I am reviewing the end of chapter problems and run across a little snag on Prob. 105-001. The problem states:
A system of parallel T-shaped reinforced concrete beams support a floor with the following service loads: DL = 0.085 ksf, LL = 0.15 ksf. The beams are simply supported by girders 32 ft apart and the lateral spacing between beams is 8 ft. Twenty-eight day compression strength of the concrete = 4000 psi and reinforcement is grade-60 deformed bars.
My question is how did they get d = 21.5"? Looks to me that d = 18+6/2 = 21".
A system of parallel T-shaped reinforced concrete beams support a floor with the following service loads: DL = 0.085 ksf, LL = 0.15 ksf. The beams are simply supported by girders 32 ft apart and the lateral spacing between beams is 8 ft. Twenty-eight day compression strength of the concrete = 4000 psi and reinforcement is grade-60 deformed bars.
My question is how did they get d = 21.5"? Looks to me that d = 18+6/2 = 21".
