钢框架焊接梁柱节点子结构抗倒塌性能试验研究  

Experimental study on collapse resistance of welded beam-column connection substructure of steel frame based on seismic design

作　　者：霍静思[1] 王宁[1] 陈英[1] 

机构地区：[1]湖南大学教育部建筑安全与节能重点实验室,湖南长沙410082

出　　处：《建筑结构学报》2014年第4期100-108,共9页Journal of Building Structures

基　　金：国家自然科学基金项目(51078139);教育部新世纪优秀人才计划项目(NCET-11-0123)

摘　　要：设计了2种过焊孔构造(扇形和扩大型过焊孔)的3个钢框架梁柱节点子结构试件,采用落锤冲击的加载试验方法模拟结构的动态倒塌过程。通过试验获得节点试件的破坏形态及其冲击荷载和变形时程曲线,分析试件冲击荷载和位移时程响应规律以及子结构动态转角和耗能变化趋势。结果表明:过焊孔构造对节点在冲击荷载作用下的破坏形态和力学性能有显著影响,补强焊缝可有效改善扩大过焊孔节点的上翼缘压曲;与扇形过焊孔相比,扩大型过焊孔节点试件具有更好的抗冲击转动能力,其极限转角满足FEMA 350中的转角限值(θ=0.064 rad)要求;通过分析冲击过程中试件截面内力发展规律可知,由于节点过早破坏限制悬链线效应的形成,该类型节点子结构由于节点转动能力不足不能充分发挥悬链线效应。Three welded beam-column connection substructures of steel frame with two kinds of weld access holes （ fan-shaped and enlarged weld access hole） were designed based on the Chinese seismic code and relevant references. The impact tests using drop-hammer were carried out to simulate the dynamic behavior of structural progressive collapse. The failure modes and time histories of impact load and deformation were obtained, and the response regularity of the impact load and deformation time histories were analyzed as well as the dynamic rotation and energy dissipation of the substructure. Test results show that the structural detailing of weld access hole has a significant effect on bearing capacity and deformation performance of the connections under impact loading. The reinforced weld can effectively improve the local buckling behavior of hole. Compared with the specimen with fan-shaped upper flange of the welded connections with enlarged weld access weld access hole, the specimen with enlarged weld access hole has better rotation capacity to resist impact loading, while its ultimate rotation reaches the seismic design limit （0 = 0. 064 rad） of FEMA 350. The internal force development of specimens during the impact loading was analyzed and it demonstrates that the premature failure of the welded beam-column connection degrades the formation of catenary action. Therefore, the steel frame with welded connection can not give full play to catenary action due to the deficiency in connection rotation.

关 键 词：梁柱节点 动态冲击试验 动力性能 悬链线效应 抗倒塌能力 

分 类 号：TU973.15[建筑科学—结构工程] TU317.1