Direct Shear (DS)

The direct shear test offers the possibility to determine the shear strength of a soil sample, which is enclosed on all sides, at a predefined shear (failure) plane, by applying a force in opposite directions.  The test gives an indication of the volumetric behaviour of the soil in relation to a horizontal load. Results of the DS test on cohesionless soil are presented as the shear displacement versus the shear force, S, and the normal displacement. The maximum shear force is marked as peak and the conditions at large deformation as residual. With these results the peak friction angle (Φp), residual friction angle (Φ) and the cohesion (C) can be calculated.