Guidance for the treatment of high-temperature creep in the fire resistance analysis of steel structures

High-temperature creep poses a significant risk to the stability of steel structures, particularly when steel sectional temperatures rise beyond 400°C. It is crucial to address this phenomenon in fire resistance analyses of steel structures appropriately. This paper offers various design approaches to accommodate high-temperature creep in the analysis of steelframed structures. The first approach, termed the 'creep-marginal' scenario, suggests disregarding the high-temperature creep strain in steel members experiencing low stress levels and sectional temperatures. In the 'creep-moderate' scenario, where the high-temperature creep strain is considerable, it can be implicitly integrated into the analysis. For situations with substantial creep strains, such as high stress levels and high temperatures, it is essential to explicitly incorporate creep into the fire resistance analysis ('creep-significant' scenario). The feasibility of these approaches in addressing creep in fire resistance analyses is demonstrated through three case studies involving steel-framed structures at various complexity levels.