Simulation Parameter Selection and Steady Seepage Analysis of Binary Structure Slope

Xuhe Gao,Zhipei Zhang,Baocheng Cheng,Hongliang Qi,Weiping Tian,Jiachun Li

doi:10.3390/w12102747

Abstract

The selection of calculation parameters for slope excavation support design and the analysis of seepage stability is a significant challenge. This difficulty also hinders the development of slope support engineering. This study examined the right binary structure slope engineering of the K5 + 220–K5 + 770 section of the TJ1A mark of the Jiangkou-Weng’an Highway in Guizhou province. In this study, we propose and use the deep displacement monitoring data and p value test method to check the simulation parameters. Furthermore, the superposition calculation method for steady-state seepage analysis of slope geotechnical structure is proposed. A comparative analysis of the displacement, strain, stress, and safety factor of the slope after the application of pore water pressure was carried out for three slope conditions. The analysis showed that steady-state seepage has a significant effect on the displacement of the slope during the completion of excavation. As a result, a continuous distribution of strain arises on the slope along the interface between the potential sliding surface and the rock–soil layer, and then forms a continuous sliding zone. Additionally, steady-state seepage has a significant effect on the position of the displacement distribution during the initial support of the slope, leading to a significant increase in the extreme value of the shear outlet displacement of the potential slip surface of the slope and in the extreme value of equivalent strain. Finally, steady-state seepage reduces the displacement and equivalent strain upon construction of the secondary slope support. The steady-state seepage has a limited effect on the stress concentration, but reduces the safety factor calculated using the strength reduction method, in all three stages of slope excavation and support. This study enriches the analysis methods for determining the stability of a dual-structure slope during the rainy season, and provides new ideas for the safety and control of slope support projects.

Highlights

Slopes can be classified into three major categories, namely soil slopes, rock slopes, and rock-soil mixed slopes, based on their composite materials
Binary structure slopes can be further divided into soil binary structure slopes, which are soil slopes with large differences in mechanical properties between two adjacent soil layers, rock–soil binary structure slopes, where the upper layer of soil is the lower layer of the Quaternary cladding
The pore water head and pore water pressure increase from the top of slope to the stratification down the slope; the pore water pore water pressure increase from the top of slope to the stratification down the slope; the pore head increases from −0.6157 m to 80 m and the pore water pressure increases from −6.03796 KPa to water head increases from −0.6157m to 80 m and the pore water pressure increases from −6.03796

Summary

Introduction

Slopes can be classified into three major categories, namely soil slopes, rock slopes, and rock-soil mixed slopes, based on their composite materials. In rock-soil mixed slopes, the lower part of the slope is a rock layer, whereas the upper part is a soil layer. These slopes are known as binary structure slopes. Binary structure slopes can be further divided into soil binary structure slopes, which are soil slopes with large differences in mechanical properties between two adjacent soil layers, rock–soil binary structure slopes, where the upper layer of soil is the lower layer of the Quaternary cladding. Water 2020, 12, 2747 layer, and rock binary structure slopes. The binary structure slope is a common structural form in this setting as the mountain surface is overlaid by a loosely accumulated soil layer and the lower layer is hard bedrock. It is important to conduct a qualitative analysis of the factors that affect slope stability and mechanisms of slope instability, and to quantitatively evaluate slope protection methods [1,2]

Methods

Results

Discussion

Conclusion