Seismic Performance of Beam-to-Column Connections Affected by Modified Details of ESWs and Elevation Deviation of Beam Flanges [?骨箱形柱??隔板采用改良型??熔渣焊?部 及梁翼板高程差?梁柱接合抗震性能的影? ?骨箱形柱??隔板采用改良型??熔渣焊?部 及梁翼板高程差?梁柱接合抗震性能的影? ?骨箱形柱??隔板采用改良型??熔渣焊?部 及梁翼板高程差?梁柱接合抗震性能的影? ?骨箱形柱??隔板采用改良型??熔渣焊?部及梁翼板高程差?梁柱接合抗震性能的影?]

Abstract

Electro-slag welding (ESW) is one of most efficient welding methods for fabricating a diaphragm of box column.Hence ESW is widely used to connect inner diaphragms to column plates for box columns in Taiwan steel structure industry.Many previous research on full scale beam-to-column connection test indicates that seismic performance of beam-to-column connections with ESW between box column plate and diaphragm does not have good reliability.A higher probability of damage prior to sufficient nonlinear deformation is found.Some previous research also shows that fabrications and inspections of the ESW joints still have large space of improvement,and a modified weld pool details of ESW is proposed.In this study,there are four full scale beam-to-column connection tests to be carried out.Study parameters include eccentricity of beam flange and inner diaphragm in elevation,weld pool shape of ESW and protocol of loading history.The test results show the specimens with no eccentricity between beam flange and diaphragm and well ESW quality can provide 5% radian deformation capacity of inter-story drift angle.However,when an eccentricity of one beam flange thickness between beam flange and diaphragm is used,one specimen using traditional rectangular-shape weld pool details of the ESW decreases deformation capacity to 3% radian,and the other specimens using modified flared-shape weld pool details of ESW have more than 5% radian capacity of inter-story drift angle,even up to 8% radian without fracture. ? 2018, Progress in Steel Buiding Structures All right reserved.