Experimental study on seismic performance of new crimping PEC column-steel beam interior joint with post-tensioned friction damped connection
Fang Youzhen1 Zhao Kai1 Chen Yun2 Yang Yonglong1 Sun Guohua1
1. Jiangsu Key Laboratory of Structure Engineering, Suzhou University of Science and Technology, Suzhou 215011, China;
2. Suzhou Zhonggu Building Technology Co., Ltd., Suzhou 215009, China
Abstract：Two large-size interior joints of new crimping PEC column-steel beam with post-tensioned friction damped connection were tested under lateral low-cycle repeated loading, and the column layout as a design parameter was taken into consideration. From the tests, the load-rotation angle hysteretic curves were derived. Based on the test data and observation, the seismic behaviors of specimens, including the load-carrying capacity, energy-dissipation capacity, self-centering function and force transfer mechanism of joint, were studied. The results show that pretensioning bars provide restoring force and self-centering function that reduce the potential of residual drift and alleviate structural damage process, while energy dissipation elements can be used to dissipate earthquake energy and reduce the structural response; PEC column layout governs the stiffness distribution of column-beam joints and affects the mechanical process of partial self-centering connection and the damage pattern of specimens; due to the setting of pretensioning penetration bolts and pretensioning bars, the force transfer mechanism of concrete equivalent strut in the panel zone is formed, which correspondingly reduces the demand on shear resistance of steel web; before the storey drift angles for all specimens arrive at the limit of storey drift angle 0.02rad set for moderate earthquakes, the residual rotation angle basically satisfies the limit of storey drift angle 0.005rad set for small earthquakes, and when the storey drift angles exceed the limit of storey drift angle 0.035rad set for strong earthquakes, the load-carrying capacity of specimen still has the increasing tendency and the corresponding unloading residual drift angles don’t exceed 0.015rad, indicating that the connection type possesses good capacity of rotation, energy-dissipation capacity, self-centering function and collapse resistance.
