【摘要】 球面扁壳在径向朝外脉冲荷载作用下,可能发生反直观行为;在径向朝内荷载作用下,则可能发生动力屈曲。通过大量的数值分析发现,两种动力响应除各自拥有自己的响应规律外,还拥有许多共同的特点。研究结果表明:在冲击荷载作用下,当荷载为径向朝内并达到一定值时该结构发生动力屈曲,当荷载为径向朝外并达到一定值域时,该结构发生反直观行为;反直观行为和动力屈曲的位移时程曲线均具有突变现象;反直观行为的最终变形模态和荷载方向相反,动力屈曲的最终变形模态与荷载方向相同;扁壳在冲击荷载作用下,发生反直观行为和动力屈曲时,对荷载的微小扰动都极其敏感;发生反直观行为和动力屈曲时的主要内力是薄膜力;反直观行为发生机理与动力屈曲机理基本类同。更多还原

【Abstract】 The counter-intuitive behaviors of pin-ended thin spherical shell may happen under outward radial impulse loadings,while the buckling behaviors of it may happen under inward radial impulse loadings.By a large scale of numerical analyses,it is found that the two types of dynamic responses have many identical features,besides,they have their own regular characteristics.The results show that these two types of behavious will occur when the impulse loads in corresponding cases reach their crtical values;the abrupt changes exist in both displacement vs.time curves corresponding to the counter-intuitive behaviors and the dynamic buckling behaviors;the final anomalous deformation is in the inverse direction of loadings,while the final dynamic buckling deformation is along the direction of loadings;both the counter-intuitive behaviors and the dynamic buckling behaviors are all sensitive to the micro changes of loadings;the inner force resulting in the counter-intuitive behaviors and the dynamic buckling behaviors is mainly the membrane force;the occurrence mechanism of the counter-intuitive behaviors is similar to that of the dynamic buckling.更多还原