地震作用下网架结构失效模式的判定方法
Determination method of failure mode of grid structures under earthquake actions
乐风江 1陈崧 2杨富儒 3方希兵 4赵文1
作者信息
- 1. 新疆大学建筑工程学院,新疆乌鲁木齐 830047;新疆建筑结构与抗震重点实验室,新疆乌鲁木齐 830047
- 2. 新疆大学建筑工程学院,新疆乌鲁木齐 830047
- 3. 甘肃电通电力工程设计咨询有限公司,甘肃兰州 730050
- 4. 武汉理工大学土木工程与建筑学院,湖北武汉 430070
- 折叠
摘要
利用增量动力分析方法,采用多段梁单元对无缺陷网架、考虑节点几何缺陷网架、杆件几何缺陷网架以及综合考虑节点和杆件几何缺陷的网架整体结构在地震作用下的响应进行了研究.对比表明:综合考虑节点和杆件几何缺陷会加速网架结构的失效进程,施加几何缺陷没有改变网架在同一地震激励下的失效模式.从结构响应的角度,根据网架结构特征点加速度位移曲线、位移时程曲线以及网架塑性杆件比例,提出了地震作用下判别网架结构失效模式的具体标准:若网架跨中位移时程曲线发生明显跳跃,网架塑性杆件占比较小且小于一定限值,可判定网架发生动力稳定失效.若网架跨中位移时程曲线无明显跳跃但逐渐发散,且网架塑性杆件占比较高并大于一定限值,可判定网架发生强度型失效.
Abstract
The response of the grid structure without any defects,the grid structure considering nodal geometric defects,the grid structure with geometric defects of rods,and the overall structure of the grid structure considering integrated geometric defects of nodes and rods under seismic action were analyzed by incremental dynamic analysis method using multi-segment beam element.The comparative analysis shows that the integrated consideration of nodal and rod geometric defects accelerates the failure process of the grid structure,and the failure mode of the grid structure considering geometric defects is not changed under the same seismic excitation.From the perspective of structural response,a specific method to discriminate the failure mode of the grid structure under seismic action is proposed:if obvious jump phenomenon occurs in the displacement time-history curve of mid-span of the grid structure,the proportion of plastic bars of the grid structure is small and less than a certain limit value,it can be judged that the grid structure happens the failure mode of dynamic instability.If the displacement time-history curve of mid-span of the grid structure does not appear obvious jump phenomenon but gradually diverges,the proportion of plastic bars of the grid structure is high and more than a certain limit value,it can be judged that the grid structure has the failure mode of strength.
关键词
网架结构/杆件失稳/失效模式/几何缺陷/动力失稳Key words
grid structure/member buckling/failure mode/geometric defect/dynamic instability引用本文复制引用
基金项目
新疆建筑结构与抗震重点实验室开放课题(600120004)
出版年
2024
NETL
NSTL
万方数据