Tinius Olsen’s Triaxial Test System is modular in design and can be customized to match a broad range of customer requirements. The system is composed of various components, with the key items being:
- Data Acquisition system
- A 50 kN (11,200 lbf) capacity Load Frame
- Set of Electronic Measurement Transducers for load, pressure, displacement, and volume change
- Triaxial Cell complete with accessories for drained and undrained testing of 2.8” or 70 mm diameter specimens to confining pressures of up to 145 psi (1,000 kPa)
- De-aired Water Tank System for precise applications of confining, back and saturation pressures
- Data System Triaxial Software for recording, analysis and report generation in English or Metric units
This 50 kN capacity machine is delivered complete with an in-built electronic kit for triaxial testing of soil specimens up to 100 mm diameter x 200 mm long.
It consists of a sturdy twin-column construction with an integral, completely variable microprocessor controlled drive unit and LCD display comprising a touch-sensitive keyboard. It is bench-mounted for easy installation and operation.
The use of a microprocessor controlled drive system and keyboard entry offers the load frame with a broad range of features, including pause and speed reset during test, operator programming of speed and control functions, RS232 interface for computer control, and self-test diagnostics.
A strongly constructed steel case accommodates the motor drive system and safeguards against water and dirt. All operating controls are mounted on the front panel of the machine, which is angled and recessed to avoid environmental and physical damage.
Relevant Standards
- BS598, 1377, 1924; EN 12697-23, 24, 13286-47; ASTM D1883; AASHTO
Model TO-064 Specifications
. |
. |
Capacity |
50 kN |
Type |
Microprocessor-controlled stepper motor drive |
Platen speed range |
Up to 9.99 mm/min |
Rapid approach speed |
25 mm/min |
Horizontal clearance |
364 mm |
Maximum vertical clearance |
910 mm |
Maximum platen travel |
100 mm |
Specimen diameter |
38 mm (50, 75 and 100 mm can also be used) |
Key Features
- Microprocessor control
- Direct entry via a touch-sensitive keyboard
- Large on-board LED screen display
- Rapid approach and return to datum of platen
- Samples up to 100 mm diameter
- Fully variable speed to 9.99 mm/minute
Triaxial Cells Model TO-075
The cells are for testing specimens that measure 38 mm diameter x 76 mm long and 50 mm diameter x 100 mm long. The Triaxial Cell has a perspex (acrylic plastic) chamber comprising an anvil and a loading plunger. Releasing four tie rods effortlessly splits the cell. It is leak-proof up to 10 bar (10 kg/cm) fluid pressure. Cells that endure pressures of 20 bar can be made on request. An oil plug and air vent are provided for adding a thin layer of oil over water. This offers an effective sealing at the plunger for long duration tests. The cell is also equipped with four ball valves of no-volume change type, at the base.
Relevant Standards
- BS1377, ASTM D12850, D 4707
Supplied as Standard
38 mm Triaxial Cells
- TO-07501 Top loading pad, perspex, 38 mm diameter
- TO-07502 Plain perspex disc 38 mm diameter x 6 mm thick
- TO-07503 Porous stone 38 mm diameter x 6 mm thick
- TO-07504 Sheath stretcher for 38 mm diameter specimen
- TO-07505 Sand former for 38 mm diameter (1 qty)
- TO-07506 Rubber sheath for 38 mm diameter specimen (set of 12)
- TO-07507 4 x drainage tube (short), 38 mm diameter
- TO-07508 4 x drainage tube (long), 38 mm diameter
- TO-07509 ‘O’ rings for 38 mm diameter specimen (set of 4)
- TO-03105 Split mold, 38 mm diameter
Supplied as Standard
50 mm Triaxial Cells
- TO-07501 Top loading pad, perspex, 38 mm diameter
- TO-07502 Plain perspex disc, 38 mm diameter x 6 mm thick
- TO-07503 Porous stone 38 mm diameter x 6 mm thick
- TO-07504 Sheath stretcher for 38 mm diameter specimen
- TO-07505 Sand former for 38 mm diameter (1 qty)
- TO-07506 Rubber sheath for 38 mm diameter specimen (set of 12)
- TO-07507 4 x drainage tube (short), 38 mm diameter
- TO-07508 4 x drainage tube (long), 38 mm diameter
- TO-07509 ‘O’ rings for 38 mm diameter specimen (set of 4)
- TO-07510 Brass pedestal 38 mm diameter
- TO-07521 Top loading pad, perspex, 50 mm diameter
- TO-07522 Plain perspex disc 50 mm diameter x 6 mm thick
- TO-07523 Porous stone 50 mm diameter x 6 mm thick
- TO-07524 Sheath stretcher for 50 mm diameter specimen
- TO-07525 Sand former for 50 mm diameter
- TO-07526 Rubber sheath for 50 mm diameter specimen (set of 12)
- TO-07527 4 x drainage tube (short), 50 mm diameter
- TO-07528 4 x drainage tube (long), 50 mm diameter
- TO-07529 ‘O’ rings for 50 mm diameter specimen (set of 4)
- TO-07530 Brass pedestal, 50 mm diameter
- TO-03105 Split mold, 38 mm diameter
- TO-03301 Split mold, 50 mm diameter
- TO-07540 Top loading pad, 38 mm diameter (plain)
- TO-07541 Top loading pad, 50 mm diameter (plain)
Optional Accessories
- TO-07501 Top loading pad, perspex, 38 mm diameter
- TO-07502 Plain perspex disc, 38 mm diameter x 6 mm thick
- TO-07503 Porous stone, 38 mm diameter x 6 mm thick
- TO-07504 Sheath stretcher for 38 mm diameter specimen
- TO-07505 Sand former for 38 mm diameter (1 qty)
- TO-07506 Rubber sheath for 38 mm diameter specimen (set of 12)
- TO-07507 4 x drainage tube (short), 38 mm diameter
- TO-07508 4 x drainage tube (long), 38 mm diameter
- TO-07509 'O' rings for 38 mm diameter specimen (set of 4)
- TO-07510 Brass pedestal, 38 mm diameter
- TO-07521 Top loading pad, perspex, 50 mm diameter
- TO-07522 Plain perspex disc, 50 mm diameter x 6 mm thick
- TO-07523 Porous stone 50 mm diameter x 6 mm thick
- TO-07524 Sheath stretcher for 50 mm diameter specimen
- TO-07525 Sand former for 50 mm diameter
- TO-07526 Rubber sheath for 50 mm diameter specimen (set of 12)
- TO-07527 4 x drainage tube (short), 50 mm diameter
- TO-07528 4 x drainage tube (long), 50 mm diameter
- TO-07529 'O' rings for 50 mm diameter specimen (set of 4)
- TO-07530 Brass pedestal, 50 mm diameter
- TO-03105 Split mold, 38 mm diameter
- TO-03301 Split mold, 50 mm diameter
- TO-07540 Top loading pad, 38 mm diameter (plain)
- TO-07541 Top loading pad, 50 mm diameter (plain)
Oil Water Constant Pressure System -MODEL TO-081
The Oil Water Constant Pressure System from Tinius Olsen is a very versatile apparatus that can be used for a broad range of applications. This system offers an effective alternative to a Mercury and Water Constant Pressure system, particularly where space is at a minimum. The apparatus is engineered to provide confining pressure up to 16 bar to Triaxial Cells. The system has an oil pump, driven by an electric motor during the whole period of operation to maintain the preferred pressure. The unit offers variable pressure up to 16 bar, which can be decreased or increased just by turning a control knob. A transparent oil water interchange vessel is provided to convey water pressure to the test apparatus.
An effective alternative to a Mercury and Water Constant Pressure system
Model TO-081 Specifications
. |
. |
Range |
10 bar (10 kg/cm2) |
Resolution |
0.05 bar (0.05 kg/cm2) |
Accuracy pressure |
± 1% of the indicated |
Note: Supplied complete with pressure gages, flow valves and connecting pressure hose.
Key Features
- Pressure capacity, 10 bar (10 kg/cm)
- Maintains constant pressure continuously
- Use of mercury is eliminated
- Also ideal for mobile laboratories
Data Acquisition System MODEL TO-085
The Triaxial Data Acquisition System is provided with a 10 kN (1000 kgf) capacity external load cell, an LVDT displacement sensor with a range of +10 mm, a 20 bar (20 kg/cm) capacity pore pressure transducer, and a three-channel digital indicator that has been specifically designed to match the requirements of triaxial testing.
Model TO-085 Specifications
. |
. |
TO-08501 |
3-channel digital indicator |
Mode of display |
Micro-controller multi-line alpha numeric VFD display
for all simultaneous channels – no need
for channel selection |
TO-08502 |
External load cell |
Capacity |
10 kN (1000 kgf) |
Load cell excitation |
5 V, DC |
Resolution |
0.01 kN (1 kgf) |
Sensing element |
Strain gages in full bridge configuration |
TO-08503 |
Pore pressure transducer |
Capacity |
20 bar (20 kg/cm2) |
Pressure cell excitation |
5 V, DC |
Resolution |
0.01 bar (0.01 kg/cm2) |
Sensing element |
Strain gages in full bridge configuration |
TO-08504 |
LVDT displacement transducer |
Range |
±10 mm |
Sensing element |
LVDT |
De-Aired Water Apparatus MODEL TO-097
The De-Aired Water Apparatus from Tinius Olsen operates on the principle of eliminating dissolved air from the water present in the soil so as to measure the pore pressure. It is used to examine the levels of dissolved oxygen suitable for geotechnical test techniques for soil.
Advantages include:
- Time to consolidate soil samples is minimized
- For concurrent flushing of a number of hydraulic piezometer lines in dams and earth works to significantly decrease labor and disturbance at the top ends
Note: Any dissolved air in the water will result in errors in the measurement of pore pressure, especially at low pressure, and also gives incorrect or slow saturation results.
Key Features
- Oil free-vacuum pump
- Completely microprocessor controlled
- Real-time clock function included
- The unit is totally automatic and shuts off when the de-airing program is finished
Relevant Standards
Optional Accessories
- Water pump
- Pressurized storage tank, capacity 20 liters
- Valves and pressure gage (for storing de-aired water to be used in the field)
Triaxial Test Load Frame – Model TO-064

Oil Water Constant Pressure System