考虑损伤影响的平板支座抗震性能研究  

Study on seismic performance of plate bearings in spatial grid structures considering damage effect

作　　者：宋夏芸 李海旺[2] 张洁 杜雷鸣[1] SONG Xia-yun;LI Hai-wang;ZHANG Jie;DU Lei-ming(Department of Architectural Engineering,Shanxi Engineering Vocational College,Taiyuan 030009,China;College of Civil Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]山西工程职业学院建筑工程系,山西太原030009 [2]太原理工大学土木工程学院,山西太原030024

出　　处：《空间结构》2024年第2期70-79,共10页Spatial Structures

基　　金：山西省基础研究计划项目(202203021222335,202303021212307);河南省科技攻关项目(222102320106);国家自然科学基金项目(51578358)。

摘　　要：为研究强震考虑累积损伤影响的平板支座节点抗震性能,对6组12个足尺平板支座节点进行超低周往复加载试验.分析其受力过程和破坏形态,得出竖向力幅值、锚栓直径及支座挡板对失效模式、滞回性能、骨架曲线、水平刚度退化的影响.结果表明:试件的薄弱部位均为锚栓,裂纹起源于锚栓根部;随着竖向力幅值增大,二阶效应增大,支座锚栓或肋板的弯曲效应显著;在平板支座的适当位置加设挡板,可提高平板支座的抗坠落能力,且其超低周疲劳寿命提高20%以上.以试验数据为基础,建立了支座节点水平刚度退化与损伤模型的相关公式,为空间网架用平板支座的抗震能力评估提供参考.The ultra-low-cycle fatigue test on 6 groups of 12 plate bearings were carried out to study the seismic performance of plate bearings in spatial grid structures.The effects of different variables on the failure modes,hysteretic behavior,along with angles of inclination of the bearing and the anchor bolts were investigated.The variables included the vertical force,diameter of anchor bolts and extra baffles.It is found that the anchor bolt is the weakest part of the plate bearings during strong earthquakes.Cracks originate at the root of the anchor bolt and a typical ultra-low-cycle fatigue fracture micro-morphology appears.With the increasing of the vertical force amplitude,the second order effect increases,and the bending effect of the anchor bolt and the rib is significant.Adding a baffle in an appropriate position on the bearing can improve the resistance ability against falling from the base support,and its ultra-low cycle fatigue life is increased by more than 20%.A formula related to horizontal stiffness degradation and cumulative damage of the plate bearing was established,which could provide a reference for the seismic capacity evaluation of plate bearings used in spatial grid structures.

关 键 词：空间网架结构 平板支座节点 超低周循环加载 滞回耗能 刚度退化 损伤分析 

分 类 号：TU356[建筑科学—结构工程]