Direct Shear Test
Overview:
The direct shear test provides intact rock strength for a homogeneous intact sample or shear strength of discontinuity for sample with planes of weakness (discontinuity). The discontinuity may either be open or partially/completely filled. The test is conducted on a 1” x 2” plug sample, undrained with an applied constant normal load. Shear stress is applied by custom-designed endcaps, ensuring shear load is acting on a plane parallel to plug axis. Typical test output includes shear strength (as a function of normal stress), shear stress as a function of shear displacement, friction angle. Additionally, when performed on intact plug, the developed shear fracture bears a closer resemblance while compared to a saw-cut fracture, which can be further utilized in fracture conductivity and proppant embedment study.
Specs:
High technology equipment: custom-designed endcaps
Friction angle can be obtained with this test
It creates a more representative artificial fracture to mimic a natural fracture in the rock for subsequent measurements like fracture conductivity
Recommended Sample Dimensions:
Diameter – 1 inch
Length – 2 inches