Interface Testing of Geosynthetics

This equipment, ShearTrac III-DSS system, is a universal shear system capable of performing the consolidation, static, and cyclic direct simple shear phases under full automatic control. The DSS test generates a fairly homogeneous state of shear stress throughout the specimen, which provides initial stress condition, stress path, and deformation configuration that models numerous field loading conditions more closely than any other strength test such as triaxial.

This setup is capable of determining the coefficient of interface friction between a geosynthetic and soil, or between any geosynthetic combinations selected by the user. For procedures of testing a geosynthetic/soil specimen, refer to ASTM D6243 and ASTM D5321 standards. The sample size used in the setup is 305mm x 305mm (12” x 12”). This system includes a shear box spacer that can be used to test geosynthetic material with soil in the top shear box container i.e. single contact interface. The system can also be used to determine the internal shear strength of geosynthetic material, such as geosynthetic clay liners (GCL).

• Vertical Load Capacity: 160 kN (35 klbf)
• Horizontal Load Capacity: 115 kN (25 klbf)
• Vertical/Horizontal Travel: 100mm (4 in)
• Displacement Rate: 0.00003 to 7.5 mm/min (0.000001 to 0.3 in/min)
• Circular Sample size: 305 mm x 205mm (12 x 8 in)
• Rectangular Sample size: 305 x 305 x 205 mm (12 x 12 x 8 in)

• Coefficient of interface friction between soil and geosynthetic or between any geosynthetic combinations.

• Slope stabilization
• MSE retaining wall design