Question

Q4 (50 pts Extra Credit): Design the doubly reinforced concrete beam shown below if it is subjected to a bending moment of 900 k.ft f. = 4,800 psi fy= 60 ksi 27" 15"

Answer 1

MO=0.0181*60*25*29CI - 0:59x6.0121*60 D=15" d = 27" Mu = 900 koft fe's 4186 si fya boksi ballan ced beans capacity of sungly rinforced Assuming $20.90 yor balanceel fection . p=0.0181 . ) Mo- Px fy xibel? (in 0059x Ixty fo 2 Uos 8570.52 7033*60 0.25 +4.84 is = 7.17 7.77 8:45: C. 685 79165€ = 2*57*1819.0=ste hos para of auf home MI 0.9 Engon compression 3 steel ceket compression Steel 909_857,53 = 142:48 $ress is comprission steel shain dis mbuhón Es=0.003 x 7.17-205 1.954610 7.17 ts' = ĐạệceX (14k to 3 56.68 ksi Compression Shuel As'a 142.48 0.1 in 2 s6:1627 -2.8) of tensive reinforceusen 56.66 to 118 As = 7: 3.3 7.44 inz. rotal arca

for tension steel use 5 # 11 bars -7.8 in?' As = 5x1.5G for fompression steel . use 2 # 3r bars' As - 2x0'11 = 0.22 m2. 2 #3 2059 27" ?? 6ooool