Design a R. C beam of size 230 mm x 550 mm overall depth supported between an effective span of 6 m. It is subjected to a service load of 30 KN/m. Use $M_{20}$ concrete and $F_{e415}$ steel. - | $\frac{dc}{d}$ | 0.05 | 0.1 | 0.15 | 0.2 | |----------------|-------|-------|-------|-------| | $f_{sc}$ | 355.1 | 351.9 | 342.4 | 329.2 |

b = 230 mm

D = 550mm

d = 50mm (assumed)

d = 500 mm

l = 6m.

Service load = 30KN/m

$M_{20} \ \ \& \ \ F_{e415} \\ \frac{dc}{d}=\frac{50}{500}=0.1 \\ f_{sc} \ from \ \ table =351.9N/mm^2 \\ f_{cc}=0.446{\times}20=8.92N/mm^2$

$BM_{\max}=\frac{wl^2}{8}=\frac{30{\times}6^2}{8}=135KNm$

$M_d$ $=1.5{\times}BM \\ =1.5{\times}135 \\ =202.5KNm$

$M_{\max}$ $=0.138f_ckbd^2 …