Time-dependent seismic reliability analysis of rocking cold-formed steel frame based on improved HOMM.

• The improved HOMM is introduce dintoreliability analysis by the combination of Latin hypercube sampling and the Maximum Entropy Model. The error in failure probability is controlled by iteratively increasing the number of samples. • The time-dependent seismic reliability analysis frame work of structural level is recommended based on the improved HOMM. It directly targets the objective reliability index of the global limit states of the structure in the life cycle. • For the cold-formed steel structures subjected to prolonged exposure to the corrosive environment, the investigation indicates that the differences between time-dependent and time-independent seismic reliability indexes are substantial. Cold-formed steel structures are particularly sensitive to seismic loads due to their relatively low ductility and limited energy dissipation capacity. Moreover, the small thickness of cold-formed steel structures makes them more susceptible to environmental influences, leading to corrosion and material degradation. Therefore, it is essential to quantitatively assess the seismic reliability of cold-formed steel structures from a lifecycle perspective. Current structural reliability design standards often focus on the ultimate strength at the component level while neglecting the global safety of structures. Additionally, it tends to neglect the time-variant characteristic of structural resistance due to the corrosion and degradation of materials. Therefore, the time-dependent seismic reliability analysis framework was proposed at the global structural level based on an improved high-order moment method (HOMM). It directly addresses the objective failure probabilities at the global structural level and takes into account the resistance degradation of structures in the design reference period. A comparative analysis of the time-dependent seismic reliability between rocking cold-formed steel frames and rigid cold-formed steel frames is conducted, focusing on load-bearing capacity limit states and deformation capacity limit states. The investigation indicates that the differences between time-dependent and time-independent seismic reliability indexes are substantial. For cold-formed steel structures subjected to prolonged exposure to the corrosive environment, it is recommended to consider the time-dependent degradation of structures. [Display omitted] [ABSTRACT FROM AUTHOR]