Dynamic Response Analysis of Non-Uniform Unsaturated Soil Layer Roadbed under Uniform Moving Load

The soil layer of the roadbed is an uneven unsaturated soil layer in practical engineering. The goal of this article is to consider the uneven gradient distribution of soil particle compression modulus and soil skeleton compression modulus along the depth of unsaturated roadbed soil. Introducing an uneven gradient factor is to propose a power function continuous variation model for the soil particle compression modulus and soil skeleton compression modulus of the roadbed soil along the depth of the soil layer. Then, the model is coupled with Biot’s theory of unsaturated porous media to establish a dynamic response model for non-uniform unsaturated soil layer roadbed under uniform moving loads, and provided a method for using Fourier series to solve the model. Analysis the influence of soil particle compression modulus and soil skeleton compression modulus on the dynamic response of unsaturated soil layers under uniform moving loads. The results indicate that the deformation displacement is positively correlated with the non-uniform gradient factor of modulus. The deeper the depth, the weaker the influence of the non-uniform gradient factor on the peak pore water pressure. At the same location from the vibration source, the influence of the non-uniform gradient factor of soil particle compression modulus on the peak pore water pressure is not significantly different from the influence of soil skeleton compression modulus on the peak pore water pressure. However, the gradient factor of soil particle compression modulus has a greater impact on the peak deformation displacement than the factor of skeleton compression modulus. Thus, clarified the influence of the non-uniform gradient factor of soil particle compression modulus and soil skeleton compression modulus along depth on the dynamic response of the non-uniform unsaturated soil layer roadbed under uniform moving load.