摘要
为研究常幅加载下管球组合试件的超低周疲劳性能,采用3种常幅加载制度对6个管球组合试件进行轴向大位移循环往复加载的超低周疲劳试验,观察试件的变形特征,并对其滞回曲线、骨架曲线、承载力退化、累积耗能等抗震性能指标展开研究。结果表明:滞回曲线均呈Z形,有明显的捏缩现象,耗能能力较差;随着压幅值的增大,试件的极限抗压承载力和变形能力均有所下降;试件破坏均发生于钢管中部的塑性铰区域,经历了弯曲、凹陷、裂纹、开口、断裂5个过程,承载力的退化与破坏形态相对应,分别经历了线性下降、逐步趋缓、急剧下降、再次趋缓、突然丧失承载力5个阶段,据此建立了损伤程度等级、损伤指数与试件破坏形态之间的对应关系,以期为螺栓球网格结构的损伤评定提供参考。
In order to study the ultra-low cycle fatigue performance of tube-ball composite specimens under constant amplitude loading,the ultra-low cycle fatigue tests of six tube-ball composite specimens under axial large displacement cyclic loading were carried out by three constant amplitude loading systems.The deformation characteristics of each specimen were observed,and the seismic performance indexes such as hysteresis curve,skeleton curve,bearing capacity degradation and cumulative energy dissipation were studied.The results show that the hysteresis curves are Z-shaped,with obvious pinching phenomenon and poor energy dissipation capacity.With the increase of compression amplitude,the ultimate compressive bearing capacity and deforma-tion capacity of the specimen decrease.The failure of specimens occurs in the plastic hinge region in the middle of the steel tube,which experiences five processes including the bending,depression,crack,opening and fracture.The bearing capacity degrada-tion corresponds to the failure mode,which experiences five stages including the linear decline,gradual slowdown,sharp decline,re-slowing and sudden loss of bearing capacity.The corresponding relationship among the damage degree grade,damage index and failure mode of specimens is established,so as to provide reference for the damage assessment of bolted spherical grid structure.
作者
田晋鹏
李海旺
王兴宇
宋夏芸
张洁
TIAN Jinpeng;LI Haiwang;WANG Xingyu;SONG Xiayun;ZHANG Jie(College of Civil Engineering,Taiyuan University of Technology,Taiyuan030024,China)
出处
《中国科技论文》
CAS
北大核心
2022年第8期887-892,共6页
China Sciencepaper
基金
国家自然科学基金资助项目(51578358)。
关键词
螺栓球网格结构
管球组合试件
抗震性能
超低周疲劳试验
常幅加载
bolted spherical grid structure
tube-ball composite specimen
seismic performance
ultra-low cycle fatigue test
con-stant amplitude loading
