Experimental and Numerical Investigation on Mechanical Behaviour of Gravel Soils

Gravel soil is a distinctive geological material comprising a blend of soil and gravel fragments. Unlike pure soil, the mechanical behaviour of gravel soils depends largely on the properties of the gravel particles, including their sizes, contents, spatial distributions, and shapes. This study aims to investigate the impact of gravel content and stress level on the mechanical properties of gravel soils. Firstly, undrained triaxial compression tests are conducted to determine the shear strength of the soil matrix with fine particles ( \(d<7.5\) mm). Then, a series of finite element simulation of plane strain tests using a clay hypoplastic constitutive model is carried out to assess the shear strength and deformation behaviour of gravel soils with varying contents of gravel ( \(d>7.5\) mm). The numerical simulation indicates that the presence of gravel particles enhances shear strength while reducing the potential for deformation in gravel soil.