Rock Direct Shear Tester (RDS-300)
RDS-300 Direct Shear Testing System

The GCTS RDS-300 Direct Shear System is a great apparatus for testing a variety of rock specimen configurations. This automated system includes advanced software to make the testing experience an easier and more enjoyable one. Many add-ons can supplement this system to enhance and broaden testing.


  • Closed loop servo control of double acting (push/pull) 500 kN (50 ton) shear load actuator with ±50 mm stroke and 500 kN (50 ton) normal load capacity with 100 mm stroke.
  • Includes adjustable locking mechanism to prevent rotation of the top box in any one direction, two directions, or none (fixed so that no shear plane rotations are allowed).
  • Accepts 150 mm (6") diameter samples & 100 x 100 mm cubical specimens up to 150 mm high.
  • Software for automatic performance of direct shear tests with constant normal stress or constant normal stiffness.
  • Capable of performing unconfined compression tests or triaxial tests with optional hardware.
  • Other load capacities and specimen size dimensions are available, including large-scale test systems for shear loads of up to 1,000 kN (100 ton) and specimen sizes up to 300 mm diameter or side.



The GCTS Direct Shear System for Testing Equipment is a versatile device for testing a wide range of rock specimen configurations. Cylindrical cores, cubes, prisms, and rock fragments can be used to determine the shear strength.


This system features electro-hydraulic closed-loop digital servo control of the shear and normal loads for test automation. The included software program accepts inputs from the normal load sensor and up to three normal deformation sensors (the software calculates automatically the average normal deformation). Loads or deformations for both the shear and normal actuators can be set to automatically perform advanced tests such as the Constant or Calculated Normal Stiffness Direct Shear Test.


This system can be provided with an optional triaxial cell, unconfined loading platens, indirect tension (Brazilian) platens, etc. to perform most of the laboratory mechanical tests required for rocks.



  • 500 kN shear load capacity
  • 500 kN axial load capacity
  • 1000 kN/mm frame stiffness
  • 150 mm maximum specimen diameter 
  • 150 mm maximum specimen height


Please contact GCTS for full specifications.