Risk‐targeted seismic design for collapse safety of SMA‐based structures considering temperature effect

Abstract

AbstractA risk‐targeted seismic design method for shape memory alloy (SMA)‐based structures is proposed in this study, taking account of temperature effect and the uncertainty of regional temperature distribution. To facilitate discussion of the overall performance of SMA‐based structures, the thermo‐mechanical behaviors of both SMA material and SMA‐based self‐centering braces (SMA‐SCB) are first introduced, where an advanced simulation method is developed. Aided by an extensive parametric study, the collapse capacity of SMA‐based structural systems is comprehensively investigated, where the predominant factors controlling the seismic performance are revealed. Based on the results, the concepts of collapse capacity‐temperature function and temperature‐modified collapse capacity are introduced in this study. The temperature‐modified collapse capacity combines the information of regional temperature distribution and temperature‐dependent behavior of the SMA‐based structures. The temperature‐modified collapse capacity is developed to determine the risk‐targeted design spectral acceleration for satisfying the specific risk‐targeted performance objective. The procedure of the proposed design method is then demonstrated by examining a three‐story SMA‐based self‐centering braced frame (SMA‐SCBF) building in a selected seismic‐active region, followed by a probabilistic method to evaluate the collapse risk. The results manifest that by using the proposed design method, the SMA‐based structures can successfully achieve acceptable performance during the design service life, and the influence of temperature should be carefully taken into consideration in both assessment and design phases.