Abstract: Key requirements of GB 51249-2017, Code for Fire Safety of Steel Structures in Buildings was interpreted, and comparative study on calculation of fire resistance of steel structure based on code and numerical simulation was conducted. The results showed that: code has good feasibility to steel members under fire with three or four sides in statically determinate structures; for steel members under fire with three or four sides in statically indeterminate structures, the applicability needs further study.

Key words: steel structure; fire prevention; numerical; temperature field; fire resistance rating