Abstract: In order to reveal the influence of advanced-peak rainfall infiltration on the matrix suction distribution of a two-layered foundation,the following research work is carried out.Firstly,based on Richards transient unsaturated seepage equation and Gardner soil water characteristic function,the water transport model of a two-layered unsaturated foundation for advanced-peak rainfall infiltration is established,and the transient analytical solution of matrix suction for advanced-peak pattern rainfall infiltration into a two-layered foundation is established by Laplace transform.Then,the analytical results are compared with those obtained from the finite element simulation,which indicates that the analytical solution is reasonable.The research results provide a convenient means to predict the evolution characteristics of matrix suction of a two-layered foundation for non-uniform rainfall infiltration,and can provide technical support for the evaluating bearing performance and reducing disaster of a foundation in rainy season.

Key words: unsaturated soil, two-layered foundation, rainfall infiltration, matric suction, analytical solution