摘要
随着冲击现象发生频率的增加,在冲击荷载作用下大跨空间结构的动力响应和灾害性研究已经成为学者们开始关注的新兴课题.本文选用K6型单层网壳结构模型,利用通用非线性有限元软件ANSYS/LS-DYNA进行数值模拟,建模时考虑材料应变率的影响.首先介绍了分析采用的模型相关参数以及有限元计算的基本理论,然后选择不同的冲击点对网壳结构进行竖向冲击荷载作用下的动力响应分析.结果表明,在顶点冲击作用下结构会发生大面积的整体倒塌;在相同的冲击力作用下结构的位移、轴力、能量、速度等动力响应均随着冲击点离顶点越远而越小;顶点是结构最不利的冲击荷载受力点,在网壳抗冲击设计时应该对顶点处杆件进行加强.
With the increasing of impact phenomenon, dynamic response and disaster research of large span space structures under impact loading has become a new topic which is Concerned by researchers. In this paper, a K6 single-layer reticulated shell structure model was established with ANSYS/LS-DYNA, and the influence of material strain rate was considered. Firstly, the model parameters which were used in the analysis and the basic theory of finite element method were introduced. Then different points were chosen to do dynamic response analysis of reticulated shell structure under vertical impact loads. The results show a large area of the structure overall collapse will occur under vertex impact loads. The displacement, axial force, energy and speed of structure response decreases gradually farther from the vertex point under the same impact force. Because the vertex is the most unfavorable impact force point, the bar around the vertex point should be strengthened in the shell impact design.
出处
《空间结构》
CSCD
北大核心
2014年第2期23-28,共6页
Spatial Structures
基金
国家科技支撑计划项目(2011BAK12B07)
国家自然科学基金项目(51278236)
关键词
冲击荷载
单层网壳
不同点冲击
破坏模式
impact load
single-layer reticulated shell
different points of impact
failure mode
