Sandy Loam Soil Shear Strength Parameters and Its Colour

Abstract

The shear strength parameters—the shear cohesion and the internal friction angle—are important parameters in calculating the shear strength of the soil, which is a mechanical property reflecting the resistance of the soil to shearing. This article embeds shear cohesion and internal friction angle results of the sandy loam soil measured using the direct shear test relying on drawing the Mohr–Coulomb line. Beside the shear strength parameters, this article contains colour results of the tested soil at different moisture contents, measured using the spectrophotometric technology in the visible band (spectrum; 400–700 nm). Measuring the soil colour might be the simplest way in the field for identifying the shear strength and its parameters in case of having the colour linked to the shear strength parameters through the moisture content of the soil, and this target is achieved by laboratory empirical work. The process of correlating the soil colour and the shear strength parameters at different moisture contents is presented in this article. The measurements were carried out at the Hungarian University of Agriculture and Life Sciences (MATE—Department of Vehicle Technology Laboratory).

Keywords

• soil shear strength
• sandy loam soil
• direct shear test
• Mohr–Coulomb diagram
• shear cohesion
• internal friction angle