GDS Instruments (A division of Global Digital Systems Ltd) products

Geotechnical Testing Systems - Dynamic Triaxial Testing

GDS - Enterprise Level Dynamic Triaxial Testing System

The GDS Enterprise Level Dynamic Triaxial Testing System (ELDYN) is an entry level dynamic triaxial system, based on an axially-stiff load frame with a beam mounted electro-mechanical actuator. The ELDYN has been designed to fulfil the demand within the geotechnical laboratory testing industry for a lower cost, more basic dynamic triaxial testing system, yet still perform to the very advanced standards that customers expect from GDS.

GDS - Advanced Dynamic Triaxial Testing System

The Advanced Dynamic Triaxial Testing System is a high-end, no compromise testing apparatus combining a triaxial cell with a dynamic actuator capable of applying load, deformation and stresses up to 5Hz. The cell itself is screw-driven from an integral base unit housing the motor drive. Axial force and axial deformation are applied through the base of the cell. The system can be combined with a dynamic cell pressure actuator such that cell pressures may also be applied dynamically up to fundamental frequency of 5Hz.

GDS - True Triaxial Apparatus

The GDS True Triaxial Apparatus (GDSTTA) has the defining characteristic that, unlike conventional triaxial apparatus, all three principal stresses can be controlled independently, rather than just two in a conventional triaxial system. This allows a wider range of complex stress paths to be performed. This dynamic cyclic system is powered by advanced electro-mechanical actuators. Vertical and one horizontal axis are loaded via the dynamic actuators (axis 1 and 2), stress control is provided for the 2nd horizontal axis, (axis 3) via cell pressure.

Geotechnical Testing Systems - Hollow Cylinder

GDS - Small-Strain Hollow Cylinder Apparatus

The GDS Hollow Cylinder Apparatus (HCA) allows for rotational displacement and torque to be applied to a hollow cylindrical specimen of soil. Using this device it is possible to control the magnitude and direction of the three principal stresses.

Geotechnical Testing Systems - Resonant Column

GDS - Resonant Column Apparatus (Stokoe Type)

For many years the resonant column apparatus has been used in research and commercial laboratories to estimate values of the shear modulus, G, and damping ratio, D, for soil specimens across the small to medium strain range (< 1 %). The variation in these parameters with increasing strain magnitude allows engineers to conduct dynamic response analyses, such as those using finite element and non-linear analytical methods, which enable performance assessment of natural and engineered structures subjected to dynamic and cyclic loadings.