摘要
应用有限元软件ANSYS LS/DYNA建立60m跨度K8型单层球面网壳与圆柱形冲击物的模型并进行数值分析,得到网壳竖向变形、主要杆件受力及塑性发展三方面的结构动力响应。归纳出顶点竖向冲击荷载下网壳结构的四种失效模式:杆件损伤,杆件破坏,局部凹陷,整体凹陷。通过考察网壳杆件受力与破坏形式,得出杆件按时间顺序可能出现的三种受力状态:剪切、弯曲、拉伸,以及四种破坏形式:剪切、弯曲、拉弯、拉伸。研究发现:破坏的杆件起到将冲击物的能量传递给网壳主体的重要作用,杆件破坏形式预示其传递能量的能力,而传递的能量是决定的网壳动力响应的主要因素,更重要的是网壳的失效模式是依据最大动力响应定义的。由此,以能量传递为媒介,建立了杆件破坏形式与网壳失效模式间的对应关系。
Four failure modes of a reticulated dome including member slight damage failure,member broken failure,local dent failure and global dent failure were generalized according to its dynamic response,when a single-layer reticulated dome was subjected to vertical impact load on its apex.And failure members were all in impact zone.Dynamic response of failure members was given out.Then,there were three states of load before failure of members: shear,bending and tension appeared in time order.Besides,four failure types of members were put forward basing state history before failure: shear,bending,bending and tension as well as tension.Based on analysis of energy transfer,the relationship among failure types of members,failure modes of reticulated dome and energy transferring were put forward: failure modes of reticulated dome were decided by the maximum dynamic response;then,the maximum dynamic response was decided mainly by the energy in the outer zone of reticulated dome;the ability of transferring energy could be judged by failure types of members in impact zone.
出处
《振动与冲击》
EI
CSCD
北大核心
2009年第10期54-59,共6页
Journal of Vibration and Shock
基金
国家自然科学基金重大研究计划重点项目(90715034)
关键词
球面网壳
冲击
破坏形式
失效模式
失效机理
动力响应
能量
reticulated dome
impact
failure type
failure mode
failure mechanism
dynamic response
energy
