挡水结构水下爆炸作用的离心模型试验

水下爆炸包括冲击波和气泡脉动,两者能量相当,均会对结构产生毁伤作用。水下爆炸载荷试验唯有在离心机内才满足相似关系,设计试验时宜在离心机负载范围内尽可能增加模型尺寸以减小边界效应。针对挡水结构,在离心机内布置压力传感器、高速摄像机、加速度计及应变片测试了冲击波、气泡脉动载荷及结构产生的动力响应。通过试验对比了水下爆炸和空爆产生的载荷,分析其引起结构动力响应的差异。对于水下爆炸,重力加速度的增加引起气泡脉动冲量的减小,而气泡脉动产生的峰值应变基本与气泡冲量呈线性关系,因而模拟气泡脉动对结构作用时应考虑重力效应。

Centrifuge modeling on dynamic response of water retaining structure by underwater explosion

Underwater explosion consists of two procedures, i.e. shock wave and bubble oscillation, both of which take up approximately 50% of the explosive energy and would cause severe damage to structures. A satisfaction in similarities of both shock wave and bubble oscillation is only possible in centrifuge. Contain-er for underwater explosion in centrifuge should be as large as possible to minimize boundary effects. Shock wave, bubble oscillation, and the induced dynamic responses of structure are recorded by water pressure sensor, high speed camera, accelerometers and strain gauges. This paper compares the difference between the shock load and dynamic responses of air blast and underwater explosion. Then,by changing the centrip-etal acceleration, gravity effects on the bubble impulse are investigated. The research also finds that there is linearity between the peak strain bubble oscillation and bubble impulse. Thus, the effects of gravity should be considered in the simulation of bubble pulse on structure.