Transient model of unsteady creep of sliding zone soil under cyclic dynamic load based on fractional derivative

Abstract

The shear mechanical behavior of soils in the slip zone under cyclic loading is of great importance for the stability analysis of landslides. In this paper, an experimental device is developed to study the nonlinear deformation mechanism of soil in sliding zone under cyclic load. Based on field tests and model tests, the change of shear strength parameters of the soil in the slip zone with cyclic loading parameters was investigated. Based on the deformation characteristics of slip zone soils under cyclic dynamic loading, the unsteady creep transient model based on fractional derivative is established, and three deformation types of sliding zone soil are described: stable, critical and destructive. The Levenberg-Marquardt (LM) algorithm is used to fit the nonlinear curves, and the applicability of the model is also verified. This research method provides a test apparatus and a method for studying the deformation characteristics of slip zone soils under cumulative loading.