近场水下爆炸作用下箱形梁整体损伤特性研究

摘要

When warship acts against underwater near-field explosion and coupling resonant motion takes place, the damage characteristics of the warship deserves an advanced research. A box-like beam was designed as an object floating on water, and a numerical simulation method was presented to study on the dynamic response of the beam subjected to underwater explosion located closely. Finally, experiments were carried out to verify the simulation method. The results show that numerical results agree well with experimental ones, and it proves the method reasonable. When the first-order mode frequency of beam is close to that of underwater explosion bubble oscillation, with the increase of the ratio of stand-off to maximum bubble radius, the response mode of beam will take a change from plastic bending in sagging condition into elastic whipping motion.%当水下近距爆炸载荷对舰船产生耦合激励作用时,舰船的总体损伤特点是一个值得深入研究的问题.以水面箱形梁模型为研究对象,建立了梁模型在水下近距爆炸载荷作用下动态响应的有限元仿真方法,最后利用数值仿真和具体试验相结合的方法,对自由梁在水下特定爆炸工况下的整体损伤特性进行了研究.结果发现:数值计算结果和试验结果具有较好的一致性；在爆炸气泡脉动频率与梁模型一阶湿频率相近的条件下,随着爆径比的增大,梁的整体响应状态由整体中垂塑性弯曲转变为鞭状运动.