不同形状装药爆炸作用下地下管廊动力响应研究

Study on Dynamic Response of Underground Pipe Corridor under Explosion with Different Charge Shapes

探究装药形状对地下结构动力响应的影响,运用动力有限元分析程序,建立空气、土体、钢筋混凝土管廊和炸药的模型,利用流固耦合算法,对地下管廊在土中爆炸荷载作用下的响应进行研究。试验中常将TNT堆叠为方形集团装药对地下结构进行爆轰,而在实际情况,精确制导炸弹为柱状。比较柱状装药和集团装药在相同当量以及同一起爆位置爆炸时的响应,当比例距离小于0.5 m/kg^(1/3)时,柱状装药在相同比例距离的轴向超压大于径向超压,前者峰值约为后者峰值的1.12~4.79倍,在比例距离小于0.4 m/kg^(1/3)时,柱状装药径向超压大于同比例距离集团装药的轴向超压,爆炸冲击波沿装药轴向传播速度大于径向传播;两种装药顶爆作用下,主要是结构顶部竖向响应的区别,柱状装药对结构顶板的竖向扰动持续时间更长,顶板竖向加速度峰值在大舱顶板部位高出15.6%,小舱顶板部位高出12.2%,对于侧墙部位的加速度和位移影响并不是很大。表明装药形状对于结构动力响应有一定的影响,研究结果对防护工程结构以及内部附属设施设计提供参考。

The influence of charge shape on the dynamic response of underground structures was investigated.A dynamic finite element analysis program was used to establish a model consisting of air,soil,reinforced concrete pipe corridors,and explosives.The response of the underground pipe corridor under explosion load in soil was studied using a fluid-structure coupling algorithm.In tests,TNT is often arranged as a square group charge to detonate underground structures,while in practice,precision-guided bombs are cylindrical in shape.Comparing the response of cylindrical charges and block charges with equivalent sizes and detonation positions,it was found that when the proportional distance is less than 0.5 m/kg^(1/3),the axial overpressure of cylindrical charges at the same proportional distance exceeds the radial overpressure by approximately 1.12~4.79 times its peak value.Additionally,when the proportional distance is less than 0.4 m/kg^(1/3),the axial overpressure of cylindrical charges surpasses their radial counterparts.The radial overpressure generated by cylindrical charges is greater than that produced by group charges at equivalent proportional distances.Furthermore,blast shock waves propagate faster along the axial direction compared to radial propagation.Under top initiation conditions for both types of charges,one notable difference lies in vertical responses at the top part of structures.The vertical disturbance duration of the roof of the structure is longer,and the peak vertical acceleration of the roof is 15.6%higher in the top part of the large cabin and 12.2%higher in the top part of the small cabin,which has no great influence on the acceleration and displacement of the side wall.These findings demonstrate that charge shape indeed influences dynamic responses within structures.