摘要
为研究混合联肢部分包裹组合剪力墙(混合联肢PEC剪力墙)结构中钢连梁-PEC剪力墙焊接节点基本受力性能和抗震性能,以墙肢腹板厚度和混凝土包裹效应为设计变量,设计3个钢连梁-PEC剪力墙焊接足尺弱节点试件,进行低周往复加载试验。观察节点加载全过程中变形形态,并对其滞回性能、承载力、耗能能力、破坏模式、连梁及节点区应变等进行分析。研究结果表明:加载过程中,结构的塑性变形和损伤集中在节点区,满足“弱节点”的设计要求,钢连梁处于弹性状态;节点的破坏模式主要为节点核心区钢板剪切变形,核心区内混凝土形成斜拉杆机构效应,墙肢节点核心区下部区格混凝土局部压溃、外翼缘严重屈曲后翼缘钢板撕裂或焊缝拉断;节点破坏时,中部区格距节点核心区上下150 mm范围内出现塑性区,型钢应变超过屈服应变,混凝土在拉压反复作用下开裂,设计时应考虑中部区格对节点受剪承载力的贡献;钢连梁-PEC剪力墙焊接节点滞回曲线饱满,承载力高,具有优良的抗震性能;节点等效黏滞阻尼系数大于0.25;节点核心区及上下区格内混凝土对钢腹板提供了良好的包裹效应,拉结筋及混凝土的设置延缓了节点区下部外翼缘钢板的屈曲,填充混凝土的试件正向承载力提高28.2%,但填充混凝土后降低了结构的耗能能力和延性。
To study the basic mechanical and seismic behavior of welded joints of steel coupling beams-partially encased composite(PEC)shear walls in a hybrid coupled partially encased composite shear walls(hybrid coupled PEC shear walls),three specimens of full-scale welded weak joints of steel coupling beams and PEC shear walls were designed and tested under low cyclic loading,using the thickness of the wall web and the concrete wrapping effect as design variables.The deformation morphology of the joint during the entire loading process was observed,and its hysteretic performance,bearing capacity,energy dissipation capacity,failure mode,strain of coupling beam and joint zone were analyzed.The results show that during the loading process,the plastic deformation and damage of the structure are concentrated in the joint zone,meeting the design requirements of weak joints,and the steel coupling beam is in an elastic state.The main failure modes of the joint are shear deformation of the steel plate in the core area of the joint,the formation of a diagonal pull rod mechanism effect in the concrete in the core area,local crushing of the concrete in the lower part of the core area of the wall limb joint,severe buckling of the outer flange,and tearing of the flange steel plate or fracture of the weld seam.When a node is damaged,a plastic zone occurs within 150 mm of the central grid from the core area of the node,the strain of the section steel exceeds the yield strain,and the concrete cracks under repeated tensile and compressive actions.So the contribution of the central grid to the shear bearing capacity of the node should be considered in design.The welded joints of steel coupling beams and PEC shear walls have full hysteretic curves,high bearing capacity,and excellent seismic performance.The equivalent viscous damping coefficient of the node is greater than 0.25.The concrete in the core area and upper and lower grids of the joint provides a good wrapping effect on the steel web.The setting of tie bars and concrete delays the buckling of the lower outer flange steel plate in the joint area.The positive bearing capacity of the concrete-filled specimen increases by 28.2%,but the energy dissipation capacity and ductility of the structure are reduced after the concrete is filled.
作者
石韵
刘少博
苏明周
刘万鹏
陈锘
贺小刚
SHI Yun;LIU Shaobo;SU Mingzhou;LIU Wanpeng;CHEN Nuo;HE Xiaogang(College of Civil Engineering,Xi’an Shiyou University,Xi’an 710065,China;College of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2023年第8期120-130,共11页
Journal of Building Structures
基金
国家自然科学基金项目(51908461)
陕西省重点研发计划(2022SF-305)
陕西省高校科协青年人才托举计划项目(20200426)。
关键词
部分包裹组合剪力墙
钢连梁
弱节点
拟静力试验
抗震性能
partially encased composite shear wall
steel coupling beam
weak node
quasi static test
seismic performance
