Probabilistic Evaluation of Self-Centering Birocking Walls Subjected to Far-Field and Near-Field Ground Motions

Abstract

This paper aims to investigate the seismic behavior of buildings equipped with self-centering birocking walls to find out the optimum location of the rocking section in the height. For this purpose, several two-dimensional nonlinear time-history analyses were carried out on different birocking structures of 4, 8, 12, 16, and 20 stories subjected to three sets of ground motions. The ground motions comprised 22 far-field (FF), 14 near-field pulse (NF-pulse), and 14 near-field nonpulse (NF-nonpulse) ground motions. The simulations have been performed utilizing the open source finite-element framework OpenSees. In this study, the first rocking section of a birocking wall was at the base and the second was considered at three different locations: one-quarter (R2-J1), half (R2-J2), and three-quarters (R2-J3) of the wall height. The seismic vulnerability of the models were statistically assessed. To determine the optimum design, a utility coefficient was defined as the average of shear and moment reduction coefficients. The results showed that R2-J2 walls are effective under FF and NF-nonpulse records, while R2-J1 walls show their best performance under NF-pulse records.