【摘要】 在明确网壳结构冲击响应关键问题的基础上,提出了实用有效的网壳结构冲击响应分析方法,包括网壳结构冲击响应的特征指标(荷载作用与特征响应)、冲击响应的分析流程与计算模型三部分。并应用此方法对典型网壳(Kiewitt-8型单层球面网壳)的冲击响应特性进行研究,分析了荷载作用特点、主要节点的速度与位移变化规律、主要杆件的应力变化规律及网壳结构的能量变化特征;结果表明网壳的荷载作用是短时超强的半正弦脉冲;响应特点是在冲击瞬间冲击区局部响应骤增,并逐渐向支座方向传播,从冲击区到支座,结构局部响应依次达到极值,此外,冲击区破坏将导致速度与能量时程曲线突变。上述成果为网壳结构抗冲击研究奠定了基础,也为其他大型结构抗冲击研究提供借鉴。更多还原

【Abstract】 The key problems in impact response study of reticulated shell were specified,and the effective analysis method for impact response of reticulated shell was established.In the method,characteristic indices(load and characteristic response),analysis schedule for impact response and its calculation model were presented.Taking Kiewitt8 single-layer reticulated shell as an example,the impact response of reticulated shell was studied.Load characteristic,law of velocity and displacement changing for main joints,law of stress changing for main members and characteristic of energy changing for structure were mainly concerned.The results show that the load is a half sine pulse with short impact duration and high peak value.The local impact response increases abruptly when impact happens,then the impact response spreads to supports gradually.The local response of structure arrives at peak value from impact zone to supports successively.Moreover,time-history curves of velocity and energy may break due to the failure of impact zone.The result lays the foundation for study on reticulated shell against impact,and provides a reference to research on other large structures under impact.更多还原