Question

B. Select the required reinforcing steel for the following beam section for Mo = 130 fl-k, ML = 275 fl-k, fy = 60,000 psi, fc = 3,000 psi, b = 15'. d = 24", and d' = 2.5". Verify the section using the actual bar selection. Determine the required number of layers for the top and bottom bars. Show a sketch of the cross section indicating bar sizes and bar layout. 2.5" 15'

Answer 1

0.90 Mu (12x 130 ) + 16x975) 596 ft- Ma: M. 546662.92 ft-k de = 3oos pai tig: 60.000 px $. : 085 smar= 0.0136 from Appendix A, table A7 Axi: 0.0136 x 15x 24 = 4.90 in For 920 0136 My 685 si from Appene sher: 685 Aifrem Appendix A, table A12 Mu: 685 685 0.9 < IS 34. 5326560 in-lb - 443-88 A-k 0.9 IS 34 Mai Mai > 443-38 - 493.2 JT-K Mag = Ma-Mn = 662.22 - 493.20 - 169.02 ft-k a= 4.90x60 7.69 in 085x 3 x 15 c= 7.69 9.04 in 085 9.04-9.5 ) x 0.003 = 0.06911 0.00207 9-04 steel has yielded Therefore, compression Theoretical Arreg = 2 - I box 24-25) Aids = Anty Are Auss' - 1.57×60 - 1.57 is 2 to Try 24 8 bars (122 1.58 is) As: Anit Ang= 4.90 +1.57 2 647 is Try 7H9 bars (As = 7 in) 4.04 6. &- x0003 - (24-904)0.003 = 0.0049 < 0.005 Ø: 065+(000496-002) 250 - 0.897 Ø Mn = 0-897(7-158) 66 (24-769 + 1586021:57 - 7713-675 ink : 642.80 $t* > 596 stk