Research on the parameters of nonlinear hyperbolic model for clay-geogrid interfaces based on large scale direct shear tests

Abstract The shearing distortion characteristics of the interface of geogrid reinforced soil is investigated by using large scale direct shear tests in this study. Firstly, geotechnical experiments are carried out to determine the parameters of soils and the optimum water content of soils. Secondly, the large-scale direct shear tests are carried out under different normal stress and water content. By the results of the large-scale direct shear tests, a nonlinear hyperbolic model is established to describe the nonlinear relationship between shear stress and shear displacement of the clay-geogrid interfaces, and an equation for approximative calculation is proposed. Finally, a parametric study is carried out to investigate the influence of the water content on the shear strength of the clay-geogrid interfaces and the parameters of nonlinear hyperbolic model. The results not only reflect the relationship between water content and shear strength at the clay-geogrid interfaces, but also help to the application of geogrid reinforced soil structure in geotechnical engineering and the selection of parameters in relevant numerical analysis.