Development and validation test of a novel Self-centering Energy-absorbing Dual Rocking Core (SEDRC) system for seismic resilience

Abstract

This research focuses on the development and validation tests of a novel seismic force-resisting system named as the Self-centering Energy-absorbing Dual Rocking Core (SEDRC) system for improving seismic resilience in steel building frames. An innovative Shear Friction Spring Damper (SFSD) was developed to provide seismic energy dissipation capacity and self-centering characteristic to the SEDRC system. Two Rocking Cores (RCs), pinned to the ground, are introduced in the SEDRC system for obtaining uniform energy absorption and evenly uniform distribution of the inter-story drift. The components, working principle, and mechanical performance of the proposed SEDRC system are first described, where its notable perceived advantages compared to the existing rocking system are highlighted. A physical test on the hysteretic behavior of individual friction ring springs used in SFSDs is subsequently introduced. Then, the validation test of the SEDRC system is presented, where the key properties including the strength, stiffness, deformability, re-centering capability and energy-absorption capacity are discussed in detail. The experimental test results of the SEDRC specimen show positive and stable flag-shaped hysteretic behavior. Nearly no residual drift was observed after removing the applied lateral forces up to 6% roof drift, indicating that the SEDRC system has excellent deformability and self-centering capability. The two RCs could remain elastic during the entire cyclic loading process and promote uniform distribution of inter-story drift in the SEDRC specimen. Moreover, the computational model of the SEDRC specimen was developed and verified. Twenty-one ground motions were utilized to investigate the dynamic behavior of the SEDRC system. Numerical results further confirm the expected seismic behavior of the SEDRC system.