【摘要】 关于梁在流固载荷作用下的动力屈曲问题的理论大多数仅限于材料的弹性范围.该文根据梁的动力屈曲基本方程,采用线性强化弹塑性模型及B_R准则,对梁的弹塑性动力屈曲问题提出了一种简化计算方法.利用该方法,对梁在轴向流固冲击载荷直接作用下的情况进行了近似求解,并对初始几何缺陷和载荷持续时间进行了参数分析.算例结果表明,材料的塑性会降低梁承受动态载荷的能力,弹塑性条件下载何持续时间和几何初始缺陷对其屈曲载荷的影响规律与弹性条件下的变化趋势一致,即载荷持续时间越长,屈曲载荷越小,屈曲载荷越大.更多还原

【Abstract】 Theories for the problem of dynamic buckling of a beam subjected to axial solid-fluid impact are mostly limited to the scope of material elasticity.Based on differential equations of dynamic buckling of a beam,a simplified method is presented to solve the elastic-plastic dynamic buckling of a beam.In this analysis,an elastic-plastic model with linear strain hardening and buckling restrained(B-R) criterion was used to analyze a beam subjected to solid-fluid impact.The influences of initial geometric imperfections and the duration of loading on the dynamic buckling loads were also investigated.It is shown that material plasticity reduces the loading capability of structures.The influence of initial geometric imperfections and duration of loads in elastic-plastic condition are similar to one in elastic condition.更多还原