非饱和土地基中P_(1)波通过复合多层波阻板的传播特性研究

Propagation behavior of P1-wave passing through composite multilayer wave impeding block in unsaturated soil

基于弹性波在非饱和多孔介质与单相弹性介质中的传播理论,考虑在非饱和土地基中设置一定厚度的复合多层波阻板(复合多层波阻板以3层为例),利用Helmholtz矢量分解定理,推导了非饱和土地基中P1波通过复合多层波阻板的透射、反射振幅比的解析解。通过数值算例分析了层间波阻板剪切模量和密度等物理、力学参数对非饱和土地基中P1波通过复合多层波阻板时传播特性的影响规律。结果表明:复合多层波阻板中层间波阻板材料的剪切模量对透、反射系数影响显著,层间波阻板材料的密度对透、反射系数影响较小。故严格控制层间波阻板的剪切模量可以获得很好的隔振效果,这为复合多层波阻板在地基振动控制领域中的应用提供理论指导。

Based on the propagation theory of elastic waves in unsaturated porous media and single-phase elastic media,consider⁃ing that a composite multilayer wave impeding block(WIB)with a certain thickness is set in unsaturated soil(composite multilayer wave impeding block with 3 layers as an example),and using Helmholtz vector decomposition theorem,the analytical solutions of transmitted/reflected amplitude ratio of P1-wave passing through composite multilayer wave impeding block in unsaturated soil are derived.The influences of physical and mechanical parameters such as shear modulus and density of interlayer wave impeding block on the propagation characteristics of P1-wave passing through composite multilayer wave impeding block in unsaturated soil are ana⁃lyzed by numerical examples.The results show that the shear modulus of interlayer wave impeding block material has a significant influence on the transmission/reflection coefficient,and the density of interlayer wave impeding block material has little influence on the transmission/reflection coefficient.Therefore,strictly controlling the shear modulus of interlayer wave impeding block can obtain better vibration isolation performance,which provides a design criterion for the application of composite multilayer wave im⁃peding block in the field of foundation vibration control.