Test study on seismic performance of large-size interior joint between innovative PEC column-steel beam with frictional energy-dissipation t-stub connection
FANG Youzhen;GU Qiang;WAN Caizhi;SHEN Xiaoming;SUN Guohua;Jiangsu Key Laboratory of Structure Engineering,University of Science and Technology of Suzhou;Wuzhong Construction drawing Inspection Center of Suzhou;
Primary design parameters as axial compression,column layout and thin-walled built-up section were taken into consideration,4 large-size interior joints of innovative PEC column-steel beam with frictional energy-dissipation T-stub connection were fabricated and investigated by pseudo-static tests. Based on the test data and observation,the specimens global behaviors were studied,including the load-carrying capacity,the mechanical performance of connection,force-transferring mechanism of the panel zone and the failure mode. The results showed that the crimping of flange can well confine the concrete to achieve the seismic design principle of "strong column weak beam"; axial compression increase its initial flexural stiffness but lower the load-carrying capacity and accelerate the yield process of beam section due to its second-order effect; the force-transfer mechanism of concrete equivalentstrut in the panel zone alleviates its shear demand attribute to through-out bolts,and all specimens exhibited various degrees of self-centering functions; the failure mode formed primary induced by yielding in the cross-section of beam nearby the end of T-stub and the connection rotation surpassed the limit( 1 /30) of maximum considered earthquake for structure,correspondingly the connection achieves the design target as energy is dissipated by friction at frequently occurring earthquake level and by yielding of beam at design basis earthquake level or maximum considered earthquake level.