盐雾环境下锈损钢框架梁柱节点抗震性能试验研究  

Experimental study on seismic performance of corroded steel frame beam-column connection under salt spray environment

作　　者：王皓[1,2] 徐善华 刘晓刚[2] 王友德[1] WANG Hao;XU Shanhua;LIU Xiaogang;WANG Youde(Key Laboratory of Engineering Structural Safety and Durability,Xi’an University of Architecture and Technology,Xi’an 710055,China;Central Research Institute Building and Construction Co.,Ltd.,MCC Group,Beijing 100088,China)

机构地区：[1]西安建筑科技大学工程结构安全与耐久重点实验室,陕西西安710055 [2]中冶建筑研究总院有限公司,北京100088

出　　处：《建筑结构学报》2022年第3期68-80,共13页Journal of Building Structures

基　　金：国家自然科学基金项目(52008414,51890903,51908455,52178165)。

摘　　要：为研究盐雾环境下锈损钢框架梁柱节点抗震性能的退化规律,对7个不同锈蚀龄期焊接梁柱节点试件开展三维形貌扫描和拟静力试验,研究了锈蚀损伤对框架梁柱节点滞回行为、破坏形态、承载性能、转动变形和耗能能力的影响。研究结果表明:锈蚀梁柱节点滞回环形状虽然较为饱满,但是其包络面积、加卸载刚度和循环圈数明显减小;锈蚀梁柱节点破坏模式均为屈曲-断裂混合破坏,其整体失效进程明显加快,不同锈蚀程度梁柱节点破坏形态有所差异;随锈蚀程度增大,梁柱节点承载面积和板件厚度不断减小,限制了节点梁端塑性发展水平,加剧了节点梁翼缘局部屈曲损伤行为,使得梁柱节点极限承载力进一步降低,当梁翼缘锈蚀率达到19.2%时,屈服弯矩、极限弯矩分别下降了28.2%和32.1%;节点梁翼缘表面点蚀坑的形成提升了节点焊接区域局部三轴应力、塑性应变水平,加速了延性裂纹的萌生和扩展,导致梁柱节点转动和耗能能力急剧退化,当梁翼缘点蚀率约为2%时,塑性转角、累积总转角和累积总耗能分别下降了44.1%、52.8%和73%;锈蚀后,梁柱节点塑性铰仍形成于梁端,等效塑性铰、塑性区长度随锈蚀程度增大而减小。In order to investigate the degradation laws of seismic performance of corroded steel frame beam-column connections under salt spray environment,3 D morphology scanning tests and quasi-static tests corresponding to seven welded beam-column connections with different corrosion time were conducted,thereby the effects of corrosion damage on the hysteretic behavior,failure mode,bearing capacity,rotational deformation and energy dissipation capacity of frame beam-column connections were studied.The results show that the shape of the hysteresis loop of the corroded beam-column connection is relatively plump,while the loading and unloading stiffness,the envelope area and the number of cycles decrease significantly.The failure mode of all corroded connections could be classified as the buckling-fracture mixed failure mode,but their failure processes are shortened significantly,and there is a difference of failure mode between beam-column connections in different corrosion stages.The bearing area and the thickness of plate gradually decrease with the increase of corrosion degree,limiting the plastic development level at beam end closed to the flange of column,aggravating the local buckling damage behavior at beam flange,which cause the more significant degradation of ultimate bearing capacity.When the corrosion degree at beam flange is 19.2%,the yield moment and ultimate moment decrease by 28.2%and 32.1%,respectively.The pits formed on the beam flange of frame connection increase the local triaxial stress state and plastic strain level of welded region of beam-column connection,accelerating the initiation and propagation of ductile cracks.As a result,the rotational capacity and energy dissipation capacity of the beam-column connection decrease sharply.When the pitting degree is about 2%,the plastic rotation,total rotation and total energy dissipation decrease by 44.1%,52.8%and 73%,respectively.After corrosion,the plastic hinge for beam-column connection is still located at the beam end,but the lengths of the equivalent pl

关 键 词：钢框架梁柱节点 锈蚀损伤 拟静力试验 破坏模式 抗震性能 退化规律 

分 类 号：TU392.103[建筑科学—结构工程]