网壳结构冲击响应分析方法及抗冲击特性研究

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。

ANALYSIS METHOD OF DYNAMIC RESPONSE AND PERFORMANCE FOR RETICULATED SHELL UNDER IMPACT

The key problems for impact response of Reticulated Shell are specified, then the effective analysis method for impact response of Reticulated Shell is established, and the method contains characteristic indicates (load and characteristic response), analysis flow and calculation model of impact response. After that, taking Kiewitt-8 single-layer Reticulated Shell for example, impact response of Reticulated Shell is study by that analysis method. Main items are characteristic of load, change law of velocity and displacement for main joints, change law of stress for main members and change characteristic of energy for structure. The results show that load is half sine pulse with short impact duration and high peak value. Local impact response increases abruptly when impact happens, then impact response spread to supports gradually. Local response of structure arrives to peak value from impact zone to supports successively. Moreover, time-histories curves of velocity and energy can break due to failure of impact zone. The result lays the foundation for study on Reticulated Shell against impact, and provides the reference for research on other large structures under impact.