20,000lbf High Capacity Geosynthetic Direct Shear Machine

20,000lbf High Capacity Geosynthetic Direct Shear Machine

High Capacity Direct Shear Machines are designed to measure the total resistance of large soil or soil/geosynthetic specimens (12in/305mm square) to horizontal shear forces. The specimens are placed in a two-piece shear box assembly, split horizontally. The bottom half is fixed while a vertical confining force is applied. Shear force is then directed horizontally against the top half of the box.

The machines use pistons powered by a stepper motor and gear box system to apply loads. Smaller pistons provide precise and sensitive application of lighter loads up to 4.4kN (1,000lbf), while larger pistons generate loads up to 45kN (10,000lbf) or 90kN (20,000lbf), depending on the model. Horizontal shear rates ranging from 0.0508 to 5.08mm (0.002 to 0.2in) per minute can be easily adjusted using digital controls. Limit switches regulate the home position and restrict horizontal displacement to 102mm (4in). Vertical loads are controlled by a precision regulator, with a calibration chart included for accurate pressure settings. The digital readout displays load values to two decimal places with ±0.25% accuracy. Displacement and shear measurements are recorded by Linear Variable Displacement Transducers, while shear load is measured by a load cell connected to the water chamber. Data is displayed on a four-channel readout and transferred via an RS 232 serial port for easy import into spreadsheet software like Excel® for analysis.

Loading and unloading specimens and shear ring assemblies is simplified with the included Compaction Table. The table’s rollers allow for easy sliding of the shear ring assembly in and out of the water chamber. Specimen compaction, geotextile placement, and preparation can all be performed on the table before the assembly is placed into the chamber.

These machines, with a maximum load capacity of 90kN (20,000lbf), operate on 110V/60Hz power. Built for durability in harsh lab environments, they feature powder-coated steel and anodized aluminum components that are corrosion-resistant. Casters on both the machine and Compaction Table ensure easy mobility. The system includes the Compaction Table, top and bottom shear rings, water chamber, transducers, data cable, and calibration chart. A clean, dry compressed air source of 120psi (827kPa) is required for operation. Customization options for specimen sizes and features are available upon request.

Key Features:

• Capable of applying loads up to 90kN (20,000lbf)
• Accommodates specimens up to 12in (305mm) square
• Precision regulators control load and displacement
• Built for harsh lab conditions with corrosion-resistant materials
• Digital readout for accurate load and displacement tracking
• Includes Compaction Table for sample preparation and easy mobility

Included Components:

• High Capacity Direct Shear Machine (90kN, 110V/60Hz)
• Compaction Table with casters
• Water Chamber
• Top and Bottom Shear Rings (12x12x4in and 12x16x4in)
• Linear Variable Displacement Transducers
• Software and Data Cable
• Calibration Chart

Specifications:

• Load Capacity: 90kN (20,000lbf)
• Air Pressure Requirement: 120psi (827kPa)
• Shear Rate: 0.0508–5.08mm (0.002–0.2in) per minute
• Accuracy: ±0.25%
• Specimen Size: 12in (305mm) square
• Power Supply: 110V / 60Hz
• Dimensions: 43 x 23 x 40in (1,090 x 584 x 1,020mm)
• Weight: 840lb (381kg)

Standards Compliance:

• ASTM D5321/D5321M
• ASTM D6243/D6243M