近距空爆载荷作用下固支方板的变形及破坏模式

Deformation and failure modes of clamped square plates under close-range air blast loads

为探讨战斗部近炸下舰船结构的变形模式,为后续理论分析和数值模拟提供实验数据,通过模型实验,分析了固支大尺寸方板在近距空爆载荷下的变形和破坏模式。在此基础上,通过测量板破裂后各裂瓣的减薄率,利用双向应变假设和体积等效原理确定了Q235钢在中部拉伸撕裂破坏模式下的断裂极限应变;根据实验模型的变形和破坏模式,基于刚塑性假设和能量密度准则提出了结构在局部爆炸载荷下的破裂判据,并对实验结果进行了预测。结果表明,随着载荷强度的增大,固支方板呈现出3种不同的变形和破坏模式;利用破裂判据对实验工况进行了预测,预测结果与实验吻合较好。

To explore the deformation modes of warship structures subjected to close-range explosion of warhead and furnish experimental data,the deformation and damage modes of clamped large scale square plates under close-range blast loading were analyzed through model experiments.On the basis of the analysis,the failure strain of Q235 steel was obtained utilizing biaxial strain hypothesis and bulk equivalent theory via measuring the thinning rate of cracked petals.Based on the experimental results,a rupture criterion of structures subjected to localised blast loading was presented after employing rigid-plastic assumption and energy density rule.Moreover,predictions for experiments were made.The results show that the clamped plates exhibit three different deformation and damage modes with the increasing of the load intensity.The predictions by making use of the rupture criterion for test conditions correlate well with the experimental results.