Analytical solution on the sensitivity of matric suction profile in soil layer which is under the condition of one-dimensional steady flow
Jian Li1, Xiyong Wu1, Long Hou2
1Department of Geosciences and Environmental Engineering, The Southwest Jiaotong University at Chengdu, Chengdu, Sichuan 610031, China
2Wanzhou District Commission of Urban-Rural Development in Chongqing Wanzhou, Chongqing 404000, China
To simulate the suction profile within unsaturated soil layer, which is under the condition of one-dimensional infiltration, the point that water potential energy is mainly composed of gravitational potential energy and suction potential energy was used. And this paper also takes the standpoint that the relationship between these two variables is reciprocal. Combined with the mass conservation law, Darcy’s law and Gardner empirical equation, an analytical solution was got. This solution could be used to describe the suction profile within unsaturated soil layer when the seepage field of this soil layer reaches steady stage and the rainfall infiltrates to the soil layer along with the vertical direction. Several conditions with different rainfall intensities q, different inverse values of air-entry pressure α and different ratio values of q/ks were examined by using this analytical solution, respectively. Compared with other factors, the rainfall intensity will take more influence on the suction profile, namely, the suction profile within unsaturated soil layer is more sensitive to the change of rainfall. The results obtained in this paper could be used as one useful reference for the research work about rainfall-induce landslide and the corresponding computer simulation.