Study on the tensile characteristics of Brazilian split in remolded loess based on resistivity and DIC techniques.

Landslides, ground fissures, and soil collapses are common natural disasters frequently associated with the tensile strength of loess. However, due to measurement difficulties, previous studies have often overlooked the tensile failure characteristics and processes of loess. This paper utilizes electrical resistance and Digital Image Correlation (DIC) technologies to investigate the changes in electrical resistance and surface strain fields during the Brazilian split test on remolded loess under various dry densities, moisture contents, and loading methods. The experimental results indicate that an increase in dry density and a reduction in moisture content decrease the tensile strength of loess. Cracks appear and electrical resistance begins to increase after reaching the peak load. The tensile strength under platen loading is lower than that under loading disc application, and the latter is not suitable for soils with high plasticity. Borehole water injection reduces the tensile strength and peak displacement of high moisture content soil samples, whereas for low moisture content samples, the peak displacement remains unchanged after water injection, but the tensile strength decreases. The failure stages of loess in the Brazilian split test are divided into four phases: stress adjustment contact phase, elastoplastic deformation phase, tensile cracking phase, and residual deformation phase. The angle between the load–displacement curves before and after the peak load is proposed as a criterion for determining brittleness. [ABSTRACT FROM AUTHOR]