Shear Creep Properties and Creep Model of Gravel Sliding Zone: A Case Study of the Zhoujia Landslide in China

Shizhuang Chen,Wei-Chau Xie,Weiya Xu,Jing Hou,Weiwei Wu,Long Yan,Mengcheng Sun

doi:10.3389/feart.2022.838183

Abstract

Creep behavior of landslide sliding zones is closely related to the long-term stability and safety of landslides. In this paper, shear creep tests are carried out on undisturbed samples of the gravel sliding zone in the Zhoujia landslide. Creep properties, such as creep rate and long-term strength, of the sliding zone are studied. The result shows that the sliding zone has typical time-dependent behavior. The relationship between the steady strain rate and shear stress can be described by an exponential equation. The long-term strengths of the sliding zone under different normal stresses are determined by using the isochronous curve cluster method. A nonlinear viscoelastic-plastic creep model is developed based on the Nishihara model. The model is shown to be suitable for describing the accelerated creep deformation of the sliding zone. The results obtained are of practical significance for understanding the deformations of the Zhoujia landslide.

Highlights

Landslide is an important geological phenomenon, in which a soil or rock mass on a slope slips along the shear failure surface (Xu et al, 2021)
Experiments on basic physical properties were conducted on the sliding zone and the results indicate that the average density is 2.3 g/cm3 and the water content is 10.3%; the average dry density of sliding zone is 2.1 g/cm3
The following conclusions can be drawn from this study: (1) Shear creep tests of three undisturbed samples taken from the Zhoujia landslide are performed under normal stresses of 851, 1,100, and 1,380 kPa, respectively

Summary

Introduction

Landslide is an important geological phenomenon, in which a soil or rock mass on a slope slips along the shear failure surface (Xu et al, 2021). The Zhoujia landslide is located on the right bank of Yalong River in Sichuan Province of southwest China, which is about 9.2–11.0 km away from the dam site of Kala Hydropower Station. The geological profile I-I′ of the Zhoujia landslide, shown, indicates that it is mainly composed of surface colluvial slope deposit (Q4col+dl), block stone layer (Q3del-k), pebbly silt (Q3del-f), and sliding zone (Q3del-h). The inclinometer profile of borehole INzj shows that significant horizontal displacement has occurred at depths of 17 and 52 m. This implies a double shear-surface structure of the landslide

Methods

Results

Conclusion