Performance Evaluation of Bridge Piers Reinforced with Shape Memory Alloys in Plastic Hinge Region: Part 2 – Optimization

Abstract

Shape Memory Alloy (SMA) rebars are emerging as a potential solution to mitigate the permanent/residual deformation of bridge piers in recent decades. The maximum damage of a bridge pier being concentrated in the plastic hinge region and SMA being the expensive material to be utilized in the large-scale structural elements, the bridge piers are reinforced with SMA in the plastic hinge regions only. The bridge piers are modeled with a non-linear finite element tool. Three variable material parameters are adopted for this study, such as the compressive strength of concrete, the yield strength of steel, and the type of SMA composition. The bridge pier models considering One-Factor-at-a-Time (OFAT) Method, and Full Factorial Design Method in the previous study (Part 1) are considered. In this paper, the results of full factorial design of the previous research are optimized using optimization techniques in order to determine the best suitable combination of these three material properties. The performance of SMA-reinforced bridge piers is evaluated based on the drift values at various performance criteria, i.e., cracking, spalling, yielding, and crushing. The results are presented in terms of the rank-wise significance for each possible combination of the considered material properties of bridge piers.