Ans For C60 75 concrete -> = 0.8- (fx -50) 0.8-(60-50) = 0.778 = 450 450 > n = 1 - (Fck- 50) = 1-(60-50) = 0.96 250 250 x= + As.fy - A's fy (Ap. fpo, 1x/83) + As.fy 7.6.n.fed) = (1777 x 1530/1.15) + (500 x400) - (914400) 0.778 Soo x (0.96 x 60) = 108.83 mm M = Ap. Fro, 1k (dp - 2.x) + As. fy (d-2x) + (As fy) ( 2 -d) =1777X1530 x(750-0.778x108.83) +500x400! (850-0-778108.83) 1.15 + 314400 x (0.778 108.83 -25) 2 M: 1835.71 KN.M