Low-cycle fatigue performance assessment of current Japanese steel beam-to-column connections determined by ductile fracture

Abstract A methodology for low-cycle fatigue (LCF) performance assessment of beam-to-column connections commonly used in current Japanese steel moment-resisting frames, such as welded flange-bolted web connections and welded connections with rectangular hollow section columns, is presented in this paper. The proposed assessment methodology is based on an empirical relationship between the number of cycles to failure and beam rotation amplitude obtained from a database of cyclic loading test results. In the empirical relationship, the effects of decreasing the moment transfer efficiency at the beam web-to-column connection due to the slip behavior of the bolts, the out-of-plane deformation of the column flange and the loss of web section due to the weld access hole are considered. The proposed approach can be applied to evaluate the comprehensive fatigue performance of current Japanese beam-to-column connections, considering the moment transfer efficiency of the beam web-to-column connection details and the steel grade.