CYCLIC DIRECT SIMPLE SHEAR TESTING MACHINE (T821)

Category: Soil

Product Code: T821

Category: SOIL

Sub-Category: CYCLIC

  • Designed to characterize soil response under one-dimensional constrained simple shear for seismic, offshore, and transportation loading scenarios, quantifying cyclic strength, cycles-to-liquefaction, modulus reduction, and damping ratio.
  • Executes cyclic shearing in stress or strain control while maintaining constant volume for saturated specimens via active height control, enabling undrained behavior representation and reliable excess-pore-pressure equivalence.
  • Supports programmable loading scripts with amplitude, frequency, dwell/hold, ramp, and multi-stage sequences, enabling repeatable research workflows and project-specific protocols.
  • Provides a broad waveform set periodic and user-defined sequences to replicate regular and irregular field loading histories with precise synchronization across channels.
  • Automates pre-shear consolidation with incremental loading, creep/hold timing, and end-of-primary detection to establish well-defined initial effective stress conditions.
  • Acquires shear force and displacement, vertical load and displacement, and (optionally) pore water pressure with high resolution; software generates τ–γ loops, G/Gmax–γ and D–γ curves, CSR, and Nliq with cycle counting and peak/valley tracking.
  • Uses NGI-type rings and sand-tight membranes to test sands, silts, and clays; interchangeable rings allow specimen optimization for material type and research aims.
  • Built on a rigid, low-compliance frame with backlash-free drives and low-friction guidance to minimize parasitic forces and enhance repeatability across small- to large-strain ranges.
  • Integrates template-based setup, real-time plotting, and auto-report export (CSV/PDF) to streamline training, routine testing, and advanced research.
  • Incorporates safety interlocks, overload/overtravel protections, and soft/hard limits to protect specimens, sensors, and operators during high-cycle programs.

STANDARDS

ASTM D6528 • ASTM D8296 • ASTM D2435 • AASHTO T216 • ASTM D4186 • ASTM D4546 • BS 1377-5 • BS 1377-6 • EN ISO 17892-5

TECHNICAL SPECIFICATIONS

  • Vertical Load Capacity: 12 kN (customized up to 300 kN)
  • Shear Load Capacity: ±12 kN(customized up to 300 kN)
  • Shear Displacement Range: ±25 mm (larger on request)
  • Frequency Range: 0.001–10 Hz (higher on request, actuator-dependent)
  • Control Modes: Stress control, strain/displacement control, mixed control; monotonic and cyclic
  • Constant-Volume Control: Active Height Control with closed-loop vertical actuator
  • Consolidation: Automatic staged 1-D consolidation with creep/hold timing and end-of-primary detection
  • Specimen Size: Ø38–100 mm (standard Ø67.5 mm)
  • Transducers: Shear load cell; vertical load cell; horizontal LVDT (≤0.001 mm resolution); vertical LVDT for AHC (≤0.001 mm); optional pore pressure transducer
  • Data & Results: τ–γ loops; G and D vs γ; CSR and Nliq; consolidation curves; cycle counters; peak/valley detection
  • Software: Template-based test setup; waveform editor; real-time multi-channel plotting; CSV/PDF reporting; calibration utilities
  • Safety: Soft/hard limits; overload/overtravel protection; emergency stop; safe-start interlocks
  • Optional ALFA Cloud integration for secure, real-time data upload, centralized storage, and web access to results.

EQUIPPED WITH

  • Rigid load frame with integrated vertical and horizontal servo actuators
  • Rings set and membranes
  • Shear and vertical load cells; horizontal and vertical high-resolution LVDTs
  • Active Height Control module for constant-volume shearing
  • Multi-channel signal conditioning and data acquisition unit
  • Control and analysis software with waveform editor and report generator

SUPPLIED WITH

  • Specimen preparation kit for DSS (membranes/rings and O-rings)
  • Alignment and assembly tools
  • Cabling and interface accessories for DAQ/control

ORDERING INFORMATION

Item Name Item Code
CYCLIC DIRECT SIMPLE SHEAR TESTING MACHINE T821A012U

Keywords: Cyclic Direct Simple Shear, CDSS, constant volume, Active Height Control, ASTM D8296, ASTM D6528, undrained simple shear, liquefaction testing, G/Gmax, damping ratio, CSR, cycles to liquefaction, NGI ring, dynamic soil testing, geotechnical lab equipment