水下近距/接触爆炸加载下圆柱壳结构动态响应行为试验研究

An experimental study on dynamic response of cylindrical shell under near-field/contact underwater explosion

为加深水下近距/接触爆炸加载下圆柱壳结构动态响应行为认识,设计典型圆柱壳结构模型,开展了水下近距/接触爆炸加载下圆柱壳结构动态响应光电联合测试,获得了冲击波、气泡与圆柱壳结构相互作用高速光学物理图像、动态应变、超压载荷、毁伤模式等试验数据。通过高速光学物理图像和三维激光扫描毁伤形态的分析,给出了冲击波、气泡与圆柱壳结构相互作用物理过程及最终毁伤模式;通过动态应变的分析,给出了圆柱壳结构迎爆面和背爆面在加载过程中应变拉伸压缩转变和响应阶段的划分;通过超压载荷的分析,明确了装药爆轰完全性以及接触爆炸加载下结构吸能对超压的影响。研究表明:爆距的变化会显著影响圆柱壳结构的毁伤形态,近距加载下圆柱壳结构主要呈现塑性大变形,接触加载下圆柱壳结构主要呈现撕裂破坏;近距加载下圆柱壳结构迎爆面空化区的形成及溃灭形成的二次加载毁伤效应不容忽视,值得深入研究;研究成果可为水下近距/接触爆炸加载下圆柱壳结构毁伤评估提供参考和依据。

In order to deepen the understanding of the dynamic response of cylindrical shell under near-field/contact underwater explosion,small-scale model of cylindrical shell was designed and then optical and electronical tests were conducted to investigate the dynamic response of the model.The physical images of the interaction of shock wave/bubble with cylindrical shell were obtained using a camera with high frequency and high resolution.At the same time,dynamic strain,overpressure and damage mode were obtained.By analyzing the damage morphology of 3D laser scanning and high-speed optical physical images,the physical process of the interaction between shock waves,bubbles,and cylindrical shell structures as well as final damage mode are presented.Through the analysis of dynamic strains,the transformation of tension and compression strains and the division of response stages of the explosion-facing surface and back surface of cylindrical shell structure during loading are revealed.Through the analysis of overpressure loads,the completeness of charge detonation and the influence of structural energy absorption on overpressure under contact explosion loading are clarified.Research results have shown that changes in detonation distance can significantly affect the damage morphology of cylindrical shell structures.Under close range loading,cylindrical shell structures mainly exhibit large plastic deformation,while under contact loading,cylindrical shell structures mainly exhibit tearing failure.The formation and collapse of the cavitation zone on the explosion facing surface of cylindrical shell structures under close range loading cannot be ignored,and the damage effect caused by secondary loading should be further studied.The research results can provide a reference basis for the damage assessment of cylindrical shell structures under near-field/contact underwater explosion.