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

Abstract

A 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.

Experimental Study of the Mechanical Properties of Full-Scale Rubber Bearings at 23 °C, 0 °C, and −20 °C

“…The results indicated that low temperatures have a notable impact on both the vertical compression stiffness and the horizontal stiffness of the rubber bearings. The study conducted by Cheng et al [10] investigated the influence of bearing temperature on the seismic response of isolated structures. The researchers observed that the effectiveness of isolation was improved when the temperature of the bearings increased within the typical operational limits.…”

Risk‐targeted seismic design: Prospects, applications, and open issues, for the next generation of building codes

“…The topic of design methods alone occupies one-third of the papers, which is not surprising given the scope of the SI. The papers by Ahmadie Amiri and Estekanci, 11 Chen et al, 12 and the two by Dolsek and co-workers, 13,14 deal with the risk-targeted design of specific structural types, while those of Fox and O'Reilly, 15 Kourehpaz et al, 16 Clemett et al, 17 and Hulsey et al, 18 with the role of seismic vulnerability (i.e., fragility) in risk-targeted design. A few papers deal with more specific issues, such as non-structural elements (i.e., Merino et al), 19 or go beyond targeting risk, that is, considering seismic resilience (i.e., Blowes et al).…”