Soil Pneumatic Triaxial Machine
STX-050 Pneumatic Cyclic Triaxial System

The GCTS STX-050 Pneumatic Cyclic Triaxial System is ideal for performing conventional triaxial tests, namely a constant rate of strain axial compression test, as well as advanced procedures such as K0 test and stress/strain path. Its versatility allows for easy performance of dynamic tests for liquefaction, resilient modulus, cyclic strength and more.


  • Closed-loop digital servo control
  • Automatically perform saturation, consolidation & shear stages
  • Static & dynamic loading
  • Stress/strain path
  • Frequencies up to 5 Hertz
  • Affordably priced
  • Optional unsaturated soils testing system upgrade also available


The GCTS Pneumatic Soil Triaxial Testing System (STX-050) is intended for performing conventional triaxial tests as well as more advanced procedures, such as the Ko test and stress/strain path tests. This system also provides the necessary versatility to easily perform dynamic tests for liquefaction, resilient modulus, and cyclic strength. The triaxial testing system includes all of the necessary software modules to perform the above tests.


The STX-050 includes an automatic ball valve to automatically perform B-value checks as well as automatically open or close drainage paths as required by different test stages. It incorporates high resolution control of the pneumatic loader, allowing it to obtain clear stress-strain curves and apply load at very low rates.


Summary results for individual test specimens can be generated in report format and files can be merged to produce a Mohr envelope plot for up to five specimens. The software will also automatically calculate the shear modulus and hysteretic damping for dynamic tests. Data acquired from all the software modules can be easily transferred to other programs like spreadsheets, databases, etc.


  • 10 kN axial load capacity
  • 1000 kPa confining pressure capacity
  • 70 mm maximum specimen diameter


Please contact GCTS for full specifications.