Abstract: The instability of most landslides is fundamentally a non-saturated creep process as on one hand, the landslide is usually in unsaturated state because landslide is directly related to the effect of water, and on another, the landslide deformation is rheological. Taking the coupling effect of seepage and creep into consideration in numerical simulation will better reflect the mechanism of landslide deformation. First of all the nonlinear creep model of unsaturated soil and its three-dimensional form acquired in previous researches of our team are verified through experimental data. Since commercial finite element programs do not provide unsaturated creep model for specific soil mass, a finite element program is developed for seepage and creep coupling. The program is used for modeling the deformation of Shuping landslide under the effect of reservoir water level fluctuation. Results show that the calculation results are close to the actual deformation monitoring values, indicating that the creep model established in this paper is reasonable, and the program is reliable, which can be applied to the estimation of long-term deformation of landslide.

Key words: landslide, long-term deformation, unsaturated soil, seepage, creep model, finite element, Shuping landslide