From a steel manual, a 457x191x82 UB has (Z_x = 1660 , \textcm^3) > 1252. Check flange width-to-thickness ratio against (\lambda_p) (compact limit). If satisfied, (M_p = 0.9 \times 355 \times 1660 \times 10^-6 = 530 , \textkNm) > 400 – OK.
): We are more certain about the weight of the steel itself (Dead Load) than we are about the weight of a crowd or a snowstorm (Live Load). Consequently, live loads get a higher "penalty" factor. Resistance ( limit state design in structural steel