Modeling of Concrete-Frozen Soil Interface from Direct Shear Test Results

Meng Xiong,Xinlei Na,Pengfei He,Yanhu Mu,Yinshan Tang

doi:10.1155/2021/7260598

Abstract

The shear behaviors of concrete-frozen soil interface are important for analyzing the performance of engineering structures buried in the frozen ground. In this paper, a series of direct shear tests were carried out to determine the concrete-soil interface behaviors at different test temperatures (19°C, −1°C, −3°C, and −5°C) and initial water contents (9.2%, 13.1%, 17.1%, and 20.8%) of soils. The interface shear behaviors, including the shear stress versus horizontal displacement, interface cohesion, and interface friction coefficient, were analyzed based on the test results. Then, a simple, nonlinear model was proposed and verified for the interface shear behaviors. The results show that the effect of initial water content and test temperature on the interface shear behavior is significant, and the peak stress increases with the increasing initial water content and decreasing test temperature. The interface cohesion is sensitive to the test temperature and initial water content, while the interface friction coefficient is insensitive to both the factors. The parameters of the simple nonlinear model can be gained by back-analyzing the test results. The predictions made by the proposed model are found to be in good agreement with the experimental results.

Highlights

Academic Editor: Yinshan Tang e shear behaviors of concrete-frozen soil interface are important for analyzing the performance of engineering structures buried in the frozen ground
Ji et al [24] tested the interface shear behavior between cast-in-situ concrete and frozen soil, and the results showed that the hydration heat of cement greatly affected the interface roughness and shear strength. ese studies indicated that the adfreeze strength can be affected by the mechanical properties of soil and structural material, test temperature, initial water content, normal stress, and so on
E initial tangent modulus decreased slightly with the increasing initial water content (Figure 4(b)). e peak shear stress decreased from 86.5 kPa to 70.7 kPa with the initial water content increasing from 9.2% to 20.8%. e test results at −3°C and −5°C are shown in Figures 3(c) and 3(d)

Summary

Introduction

Academic Editor: Yinshan Tang e shear behaviors of concrete-frozen soil interface are important for analyzing the performance of engineering structures buried in the frozen ground. Erefore, studies on the interface shear behavior or adfreeze strength of the frozen soil-structure are crucial for the engineering design and numerical simulation of the projects in cold regions. Liu et al [14] investigated the shear behavior of frozen soil-concrete interface using a temperature-controlled direct shear test system, and their results showed that temperature and moisture content had a great effect on the peak shear strength but had little effect on the residual shear strength. Wen et al [13] studied the adfreeze strength of frozen soil-fiberglass reinforced plastic interface by direct shear test in a temperature-controlled room and concluded that the cohesion was controlled by the temperature and moisture content, and the friction angle is, only affected by the moisture content. Ese studies indicated that the adfreeze strength can be affected by the mechanical properties of soil and structural material, test temperature, initial water content, normal stress, and so on. Ese models can simulate different interface behaviors; they cannot simulate the strain-hardening and strain-softening behavior simultaneously, and there are generally too many parameters that are difficult to determine

Methods

Results

Conclusion