Surrogate models for endplate beam-column connections with shape memory alloy bolts

Abstract

This paper presents the development and validation of moment-rotation backbone curve parameters for self-centering steel endplate connections with superelastic SMA bolts. In terms of influential design factors, surrogate models of response parameters are proposed using detailed finite element models of self-centering beam-column connections and statistical analysis of response parameters. The predictive surrogate models are useful for characterizing the connection backbone and self-centering response, which is essential for the performance-based design and assessment of extended endplate connections equipped with SMA bolts. Through a verification study, the accuracy of predictions using the proposed models is confirmed. The proposed surrogate models are used to assess the fragility of SMA-based beam-column connections. The results demonstrate that endplate beam-column connections with SMA bolts can provide an acceptable level of deformation capacity. Furthermore, it is found that larger diameter SMA bolts and smaller depth beam sections can reduce the probability of experiencing SMA bolt fracture by 31% and 77%, respectively.