Asphalt Direct Shear Testing Equipment
SDS-150 Direct Shear Testing System for Asphalts

The GCTS SDS-150 Direct Shear System is capable of performing multiple tests such as: conventional and advanced direct shear tests and constant normal stiffness test. With its superior design, this direct shear machine is well suited to test coarse granular materials and eliminate vibrations that may disturb or densify granular specimens.


  • Closed-loop servo control of double acting (push/pull) 50 kN (5 ton) shear load actuator with 100 mm (±50 mm) stroke & 50 kN (5 ton) normal load capacity with 50 mm stroke.
  • Normal load reaction support mounted on sliding bearings to minimize horizontal friction.
  • Accepts 150 mm (6") square specimens.
  • Software for automatic performance of direct shear tests with constant normal stress or normal stiffness.
  • Available interface platens to test soils, asphalt and geo-membranes.
  • Other load capacities & specimen size dimensions are available, including large-scale test systems for shear loads of up to 1,000 kN (100 ton) & specimen sizes up to 300 mm diameter or side.

This system features electro-hydraulic closed-loop digital servo control of the shear and normal loads for test automation. Loads or deformations for both the shear and normal actuators can be prescribed for automatically performing conventional direct shear tests as well as more advanced tests. This system can be easily programmed to perform tests such as the constant normal stiffness test where the normal load is a function of a prescribed stiffness for simulating actual compressibility of a ground shear plane (e.g. soil-pile interaction).


The GCTS Direct Shear Test System is especially well suited to test coarse granular materials including interface because of its large sample size and high load capacity.

A major advantage over conventional motorized system is that this system eliminates vibrations that can disturb or densify granular specimens.

  • 50 kN axial load capacity
  • 50 kN shear load capacity
  • 150 mm x 150 mm x 75 mm maximum size specimens


Please contact GCTS for full specifications.