用非饱和三相孔弹模型研究浅层土壤中地震波的传播特性

摘要

研究浅层土壤中声波耦合的地震波的传播特性，用于声波探雷技术的机理分析。根据浅层土壤具有孔隙度和可压缩性的特点，利用非饱和三相孔隙介质中的地震波模型，研究了土壤孔隙度、含水饱和度等参数对地震波传播特性的影响。计算结果显示：在给定的参数条件下，地震波的传播速度和衰减系数均随频率的增加而增加；纵波的传播速度随孔隙度的增加而减小，横波的传播速度随孔隙度的增加而增加；地震波的传播特性随含水饱和度的增加变化比较复杂。通过对计算结果与已发表实验结果的比较分析，讨论了解析方法的可行性，为声-地震耦合机理及其在声波探雷研究中的应用提供了一定的理论基础。%In order to study the mechanism of acoustic landmine detection, the propagation characteristics of acoustically coupled seismic waves in shallow soil are investigated. Based on the porosity and compressibility of shallow soil, the influences of parameters including soil porosity and water saturation on the propagation properties of seismic wave are discussed with the model of seismic waves in unsaturated three-phase porous medium. The calculation results show that under the given parameters, the propagation velocity and attenuation coefficient of seismic wave increase with the increase of acoustic frequency. The propagation velocities of longitudinal waves and those of transverse waves respectively decrease and increase with the increase of soil porosity. In addition, the propagation characteristics of acoustically coupled seismic waves become complicated with the increase of water saturation. The feasibility of the analysis method is discussed by comparing the calculation results with the experimental data published previously. As a result, a theoretical foundation is provided for the acoustic-to-seismic coupling mechanism and its application in the study of acoustic resonance landmine detection.