外露式钢柱脚抗震性能试验研究  

Experimental study on seismic behavior of exposed steel column base

作　　者：崔瑶[1] 刘浩[1] 李浩[1] 王晶秋 CUI Yao;LIU Hao;LI Hao;WANG Jingqiu(State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China)

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室

出　　处：《建筑结构学报》2018年第7期115-122,共8页Journal of Building Structures

基　　金：国家自然科学基金项目(51208076,51678106)

摘　　要：为研究外露式钢柱脚的抗震性能,对其进行了水平往复加载试验。试验中以锚栓的材料、数量和排列方式以及柱脚承受轴力等为变化参数,分析了不同参数对柱脚抗震性能的影响,研究了柱脚的承载力、刚度、延性及耗能能力等。结果表明：当钢柱受轴拉力作用时,外露式柱脚底板与基础分离,两侧锚栓同时承受拉力和剪力,柱脚产生明显的滑移变形,当柱转角为2%时锚栓断裂,受弯承载力为相同轴压试件的17.7%。当钢柱受轴压力作用时,外露式柱脚产生转动变形,底板绕某一点转动,翘起处锚栓受拉,另一侧底板与混凝土基础接触产生压应力。采用热轧锚栓的外露式柱脚在大变形下表现出良好的耗能能力,而采用冷拔锚栓的外露式柱脚在柱转角为4%时破坏,转角延性系数降低了约60%。当轴压比为0.2时,在不同位置增加2个锚栓后,外露式钢柱脚受弯承载力较基本试件的分别提高了10%和16%,耗能能力分别提高了19%和9%。锚栓的布置方式对柱脚的初始刚度及耗能能力影响较大。To study the seismic behavior of the exposed steel column base, a series of quasi-static experiments were conducted. The test parameters were the material of anchor rod, number and arrangement of anchor rods and axial load. The bearing capacity, initial stiffness, ductility and dissipated energy were discussed. The results show that under tensile axial load, the base plate is separated from foundation. The anchor bolts resist axial and shear forces. The specimen shows slip behavior. The specimen fails by anchor rods fracture at very early loading stage with 2% inter-story drift ratio and the bearing capacity is 17.7% of the same specimen under compressive axial load. Under compressive axial load, the specimen shows rotational behavior and the base plate rotates around a point. Therefore, the anchor rods resist tensile axial load in another side to balance the bearing resistance between base plate and foundation. The specimen with hot-rolled anchor rod shows good ductility and energy dissipation under large deformation. On the opposite, the specimen with cold-formed anchor rod shows brittle behavior and fails at very early stage when the inter-story drift ratio is 4%. The ductility is decreased by about 60% compared with the specimen with hot-rolled anchor rod. When the axial force ratio is 0.2, with two extra anchor rods in different layouts, the bearing capacity of the specimen is increased by 10% and 16%. Besides, the energy dissipation is increased by 19% and 9%. Moreover, the arrangement of anchor rods has more effects on the stiffness and energy dissipation of specimen.

关 键 词：外露式钢柱脚 锚栓 拟静力试验 抗震性能 传力机制 

分 类 号：TU391[建筑科学—结构工程] TU317.1