摘要:
冲击波在水土交界面的透射、反射压力计算尚缺乏可靠的计算理论，利用质量守恒方程、动量守恒方程以及水、土的状态方程，分别推导得到冲击波在水、土介质中传播的Hugoniot关系以及p-u曲线，进而从理论上解析得到冲击波在水土交界面处的透射和反射压力。分别建立了水中自由场、水-土分层介质场的二维数值计算模型，其中水、土参数与理论推导时采用的三相介质饱和土计算模型中的参数保持一致。计算结果表明，水土交界面透射、反射压力的理论解与数值解具有高度一致性。采用80 g TNT炸药，距离水土交界面0.1~0.9 m（比例爆距为0.232~2.089 m/kg1/3）爆炸时，得到的透射、反射压力的理论解与数值解误差均小于7%，根据解析解得出反射压力与水中入射压力之比，反射压力系数在1.6~1.8范围内；距离水土交界面0.5 m时，饱和土的含气量在0~10%范围内变化，得到的透射、反射压力的范围为63.8~70.0 MPa，此时其反射压力系数在1.55~1.70范围内。推导得出的冲击波在水土交界面透射、反射压力的计算方法，物理意义明确、计算精度高，可为开展水下爆炸对水底土中工程结构的毁伤评估提供理论基础。
Abstract:
There is a lack of reliable calculation theory for the transmission and reflection pressure of shock wave at the water-soil interface. Using the mass conservation equation, momentum conservation equation, and the equations of state of water and soil, the Hugoniot relationship and the p-u curve of the propagation of shock wave in water and soil medium are derived, and then the transmission and reflection pressures of the shock wave at the water-soil interface can be analyzed theoretically. Two-dimensional numerical models of the free field in water and water-soil layered medium field are established, in which the water and soil parameters are consistent with those in the three-phase medium saturated soil model used in the theoretical derivation. The calculation results show that the theoretical and numerical solutions of the water-soil interface transmission and reflection pressures are highly consistent. Using 80 g TNT explosives, from the water-soil interface 0.1—0.9 m (proportional burst distance of 0.232—2.089 m/kg1/3) explosion, the theoretical and numerical solutions of the transmission and reflection pressure error is less than 7%, according to the analytical solution of the reflection pressure and the ratio of the incident pressure in the water, the coefficient of the reflection pressure is in the range of 1.6—1.8; from the water-soil interface 0.5 m, the saturated soil containing pressure of the water and soil interface, the reflection pressure coefficient of the water and the water interface, the reflection pressure coefficient of the water and the water interface. At 0.5 m from the water-soil interface, the gas content of the saturated soil varies in the range of 0-10%, and the transmission and reflection pressures are 63.8—70.0 MPa, and the reflection pressure coefficients are in the range of 1.55—1.70 at this time. Derived from the shock wave in the water-soil interface transmission, reflection pressure calculation method, the physical meaning of clear, high precision calculations, can be carried out for the underwater explosion on the submerged soil damage assessment of engineering structures in the soil to provide a theoretical basis.
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