Cyclic testing of replaceable damper: Earthquake-resilient prefabricated column-flange beam-column joint

Abstract

Based on the idea of damage control, a new type of replaceable damper, namely earthquake-resilient prefabricated column-flange beam-column joint (PCFBCJ), is proposed in this paper. In order to study its seismic behaviour and post-earthquake resilience performance, five specimens were designed and six low frequency cyclic loading tests were conducted. Through these series of tests, several seismic behaviour indicators such as hysteresis curve, strain curve, skeleton curve, and energy dissipation of the joint could be obtained. Finally, the test results were verified by finite element method. This study mainly investigated the influence of several factors, such as the thickness of the flange cover plates, the number of flange bolts, the gap between the beams, and some other parameters on seismic behaviour and post-earthquake resilience performance of this joint. The results of the tests showed that this new PCFBCJ had excellent load resisting capacity, ductility and post-earthquake resilience performance, and the repaired joint could still meet the requirements of seismic behaviour; the thickness of the flange cover plates directly determined the yield load of the joint, and the reasonable gap between the beams could effectively avoid premature compression between the beams and plasticity of main components; the number of flange bolts directly affected the slippage of flange cover plates; the PCFBCJ had a stable hysteretic behaviour during loading with constant amplitude, therefore it can also be used as a damper. The refined finite element results matched the test results well, therefore, the refined finite element model could be used as an effective tool to study the performance of such joint.