Soil Testing 25 Soil strength (triaxial) Digital Tritest 50 BS , , ASTM D2850 D4767, AASHTO T296 T297. Load Frames

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1 25 Soil strength (triaxial) Load Frames This range of ELE designed and manufactured load frames is the most modern of its kind available to the discerning test laboratory.the range comprises capacities from 50 kn up to 100 kn incorporating the latest microprocessor control systems, clear on-board screen displays and a range of other high quality features. Digital Tritest 50 BS , , ASTM D2850 D4767, AASHTO T296 T297 Microprocessor control Large on-board LED screen display Direct entry via a touch sensitive keyboard Rapid approach and return to datum of platen Fully variable speed, to mm/min Samples up to 100 mm diameter This 50 kn capacity machine, designed primarily for triaxial testing of soil specimens up to 100 mm diameter x 200 mm long, comprises a rigid twin column construction with an integral fully variable microprocessor controlled drive unit and LCD display with a touch sensitive keyboard.the machine is normally bench mounted for ease of installation and operation. The use of a microprocessor controlled drive system and keyboard entry provides the Digital Tritest 50 with a wide variety of features which include pause and speed reset during test, RS 232C interface for computer control, operator programming of speed and control functions, self test diagnostics and many other features. A robustly constructed steel case houses the motor drive system with careful attention being given to the prevention of ingress of water or grit. All operating controls are mounted on the front panel of the machine which is angled and recessed to prevent physical and environmental damage. Specification Dimensions (l x w x h) Maximum vertical clearance Horizontal clearance Platen diameter Platen travel Platen speed range Rapid approach speed Weight 500 x 500 x 1470 mm 910 mm 364 mm 133 mm 100 mm to mm/min 25 mm/minute 140 kg EL series Digital Tritest 50 complete with RS 232C interface EL /01 for V AC, Hz, 1 ph EL /02 for V AC, Hz, 1 ph EL series Digital Tritest 50 Accessories EL EL EL Platen Adaptor for 159 mm diameter recessed triaxial cell bases. Platen Adaptor adapts ELE triaxial cells to 159mm diameter platens Unconfined Compression Platens and Dial Gauge Mounting Assembly The Digital Tritest 50 Screen Display 44

2 Soil strength (triaxial) 25 MultiPlex 50 BS 598, 1377, 1924; ASTM D3668, D1883; AASHTO T193 Large on-board LED screen display Fully variable speed, 0.5 to 50 mm/minute Rapid and momentary approach of platen Mechanical or electronic measurement Triaxial samples up to 100 mm diameter Applications Marshall Stability tests BS and ASTM CBR tests Quick Undrained Triaxial tests Unconfined Compression tests EL /01 MultiPlex 50 with Accessories This 50 kn capacity machine has been designed primarily for performing laboratory CBR, Marshall stability and Quick undrained triaxial tests on one load frame. It is particularly suitable for those laboratories carrying out a mix of these tests, e.g. for road construction.the compact bench mounting design comprises a twin column frame incorporated into the motorised drive system. A robustly constructed case houses the drive system with careful attention being given to the prevention of ingress of water or grit. All operating controls are mounted on the front panel of the machine. Electronic measurement is achieved using the optional EL /09 Electronic Control and Readout Unit (ECU) and appropriate load and axial displacement transducers, see catalogue section 27. With digital readout, data logging capability and download software included as standard, the Multiplex 50/ECU incorporates unique features safeguarding not only the testing equipment, but test integrity and accuracy. Among these, the ECU will check its testing mode (CBR, Marshall, etc) against the frame speed setting and will not permit the test to run if these settings are incompatible.the ECU automatically configures its logging rate per test type to comply with BS, ASTM or AASHTO standards.this means the data exported from the ECU needs no further manipulation before analysis and reporting. Finally, if the upper limits of the transducers are exceeded the ECU stops the load frame to protect the test accessories and load frame drive system. Specification Dimensions (l x w x h) Maximum vertical clearance Horizontal clearance Platen diameter Platen travel Platen speed range Rapid approach speed Weight 550 x 400 x 1470 mm 800 mm 265 mm 133 mm 100 mm 0.5 to 50.0 mm/min 40 mm/min 100 kg. EL series MultiPlex 50, mechanical load frame supplied complete with CBR stabilising bar. EL /01 for V AC, Hz, 1ph EL /02 for 110 V AC, Hz, 1 ph Close up of LED screen display of MultiPlex 50 Accessories Electronic Control and Readout Unit see EL /09 CBR Stabilising Bar see EL Platen Adaptor see EL Platen Adaptor see EL

3 25 Soil strength (triaxial) Digital Tritest 100 Microprocessor control with LCD screen display Direct entry via a touch sensitive keyboard Samples up to 150 mm diameter x 300 mm long This 100 kn capacity load frame, has an integral fully variable microprocessor controlled drive unit and LCD display with a touch sensitive keyboard.the machine has been designed as a single floor-mounting unit with the platen and controls located at optimal level for ease of operation. The use of a microprocessor controlled drive system and keyboard entry provides the Digital Tritest 100 with a wide variety of features which include; pause and speed reset facilities during test, RS 232C interface for computer control, operator programming of speed and control functions, and self-test diagnostics. Specification Dimensions (l x w x h) Maximum vertical clearance Horizontal clearance Platen diameter Platen travel Platen speed range Rapid approach speed Weight EL series Digital Tritest 100 with Accessories 550 x 630 x 2400 mm 1060 mm 458 mm 133 mm 100 mm to mm 25 mm/min 255 kg EL /01 Digital Tritest 100 as specified V AC, Hz, 1 ph Unconfined Compression Machine, Hand Operated BS 1377; ASTM D2166; AASHTO T208 Lightweight design for laboratory and field use Tests specimens up to 203 mm in length 6.6 kn capacity The unconfined compression test is an important method of determining shear strength of cohesive and semi-cohesive soils. This lightweight, hand-operated machine is self-contained and requires no pressure or electrical connections. The machine is supplied complete and ready to operate with a load ring, strain dial, platens and calibration charts. Specification Dimensions (l x w x h) Platens Load ring Strain indicator Weight 270 x 162 x 667 mm 76 mm diameter with concentric grooves for centring specimen Plated steel, complete with dial indicator and calibration charts 25 mm range x 0.01 mm graduations 26.3 kg EL Unconfined Compression Tester hand-operated Weight 26.3 kg EL Unconfined Compression Tester 46

4 Soil strength (triaxial) 25 Triaxial Cells Triaxial Cells BS 1377; ASTM D2850, D4767; AASHTO T296,T297 Working pressure up to 1700 kpa All round visibility Samples sizes 38 to 100 mm diameter Rapid assembly and dismantling Accepts a range of interchangeable submersible load transducers This range of precision made triaxial cells has been designed to meet the requirements of the modern soils laboratory.the cells have been treated to minimise corrosion. Particular attention has been paid to the quality of finish between the piston and the head. Final assembly includes the fitting of an O-ring seal and the use of special lubricant to reduce friction to a minimum and eliminate water leakage. The piston load capacity is designed to accept high horizontal forces which may be present during the final stages of a test. Each cell has five take-off positions drilled in the base for top drainage/back pressure, pore water pressure and bottom drainage. Two no-volume change valves and an anvil for strain gauge/transducer datum are supplied for fitting to the cell. A feature of these cells is that they all accept a single diameter piston.the internal height is such that a range of submersible load transducers can be fitted without any modification. Each cell will accept a range of base adaptors and various accessories for testing a wide range of specimens. Specification Model number EL EL EL Cell size 50 mm 70 mm 100 mm Max. specimen size 50 x 100 mm 70 x 140 mm 100 x 200 mm Working pressure 1,700 kpa 1,700 kpa 1,700 kpa Max. piston load 45 kn 45 kn 45 kn Vertical 380 mm 430 mm 515 mm clearance required Horizontal 155 mm 180 mm 255 mm clearance required Weight 4 kg 7.3 kg 14.3 kg Triaxial Cells with Base Adaptors 47

5 25 Soil strength (triaxial) Aggressive Materials Although all products are treated to inhibit corrosion, certain aggressive materials may attack the metal components. Examples of this are samples obtained from the seabed or containing high concentrations of sulphates or chlorides. Where aggressive materials are to be tested, ELE will be pleased to offer advice on any special requirements. Submersible load transducers Tritest 50 complete with Triaxial Cell and Transducers see EL to EL Additional items for all sizes of triaxial cells EL Grease Gun Supplied complete with one tube of silicone grease lubricant. EL Silicone Grease Lubricant Tube EL Piston Resistant Clamp to lock loading piston in position. Specimen Base Adaptor Each cell will require the correct size of specimen base adaptor relative to the size (diameter) of sample to be tested. Note: all base adaptors are double perforated for bottom drainage/pore pressure measurement.they are supplied complete with a solid disc for use in undrained tests where no drainage is required. Compatibility of Base Adaptors with Cells Specimen size Cell model number EL EL EL Maximum Maximum Maximum specimen dia. specimen dia. specimen dia. 50 mm 70 mm 100 mm 38 mm EL mm EL EL mm EL mm EL Base Adaptors 48

6 Soil strength (triaxial) 25 Axial Displacement (strain) and Load Measurement Various methods of measuring axial displacement and load can be supplied. All devices comply with the accuracy specified in BS 1377; ASTM D2850, D4767. Displacement and load transducers are supplied with a calibration certificate. EL Dial Gauge 25 mm travel x 0.01 mm. Sample up to 140 mm long. EL Dial Gauge 50 mm travel x 0.01 mm. Samples 200 to 300 mm long. Accessories 50 mm Displacement Transducer 5 pin DIN socket see EL Various methods of measuring load can be supplied, these include load rings, transducer load rings and submersible load transducers. The capacity of the load measurement device will invariably be selected with reference to the type of specimen and its size. For detailed specification of axial displacement and load measurement devices refer to EL27 and EL78 sections of the catalogue. Fitting a Rubber Membrane to a Quick Undrained Specimen As a general guide, suggested load measurement capacities are as follows: Type of Soil Capacity (max) Clays Frictional materials Soft rocks, frictional soils at high cell pressures 4.5 kn 20 kn 50 kn Sample Preparation Sample Diameter 38 mm 50 mm 70 mm 100 mm O-Ring placing tool EL EL EL EL Suction membrane device EL EL EL EL Two-way split former EL EL EL EL Two-part split mould EL EL EL ml single-tube drainage burette EL EL EL Valve complete with 6 mm connector EL EL EL EL Quick undrained tests Pressure Pad EL EL EL EL Tubing and Connector EL /10 EL /10 EL /10 EL /10 Rubber membrane (pack of 10) EL EL EL EL Length 150 mm 200 mm 250 mm 330 mm Thickness mm mm mm mm Membrane sealing ring (pack of 10) EL EL EL EL Additional items for consolidated undrained and drained tests The following items will be required in addition to those listed for quick undrained tests Porous disc (pack of 2) EL EL EL EL Filter paper drain (pack of 50) EL EL EL EL

7 25 Soil strength (triaxial) De-aired Water It is particularly important that water from which dissolved air has been removed is used in the pore pressure measurement system. Any dissolved air in the water will lead to errors in the measurement of pore pressure, particularly at low pressures. ELE De-aired Water Apparatus BS 1377 This compact self-contained unit will de-air water quickly and efficiently down to levels of dissolved oxygen acceptable for geotechnical test methods. Air is removed from the water by a vacuum system which continuously circulates the water in the tank. The unit is supplied with a clear water container which will hold a maximum of 15 litres of water. Input and output lines are formed using standard 6 mm tube connectors. Dimensions 380 x 356 x 470 mm (l x w x h). Weight 13 kg EL /01 ELE De-aired Water Apparatus For V AC, Hz, 1 ph Spares EL /10 Water Tank Weight 2 kg EL series ELE De-aired Water Apparatus Typical layout of pressure system components for Effective Stress Triaxial test 50

8 Pressure systems 26 Pressure Systems The provision and use of constant pressure systems in the geotechnical laboratory is essential if testing methods and equipment are to be fully utilised. Generally a number of independent and variable pressure sources will be required in a laboratory. Accurate and reliable monitoring systems will also be required which may range from a single pressure gauge through a whole series of transducers. ELE offer a range of products designed to supply and monitor all those parameters necessary for the successful testing of geotechnical materials. Two types of constant pressure systems are offered: 1. Air/water system operated by a pneumatic compressor 2. A motorised oil/water system Air/Water Constant Pressure System Where a laboratory requires a number of constant but independent and variable pressure sources, the use of a pneumatic compressor is recommended. Depending on the capacity and volume of the unit, a series of pressure sources can be provided to various test stations around the laboratory. Two sizes of compressor are available. 700 kpa Air Compressor Unit see EL / kpa Air Compressor Unit see EL / kpa High Output Air Compressor see EL /03 EL Bladder-type Air/Water Pressure Assembly Pressure Reducing Panels and Bladder Assemblies Compressed air must be controlled and delivered to a system designed to transfer the controlled pressure to the fluid (usually water) which applies the various test pressures, e.g. a confining pressure in a triaxial test. The pressure reducing panels are used in conjunction with a bladder-type air/water interface assembly. Each individual pressure take off from the reducing panel will require a bladder interface assembly. Connection of the reducing panels to the compressor/water trap outlet and to other reducing panels requires the use of EL Nylon Tubing. EL Bladder-type Air/Water Pressure Assembly With transparent plastic chamber for operating continuously at pressures up to 1000 kpa. A length of tubing is provided for connecting the air/water cylinder outlet to a pressure measuring system. Weight 5.6 kg Spare EL /10 Replacement Bladder EL kpa Two-way Pneumatic Pressure Reducing Panel Comprising two constant pressure reducing valves with inlet water trap and pressure indicator.the unit allows a maximum output pressure of 1000 kpa. Maximum input pressure should not exceed 1400 kpa.the panel has an inlet connector to accept EL Nylon Tubing from the Air Compressor and two 6 mm outlets for connecting EL Bladder-type Air/Water Pressure Assemblies. An outlet connector is fitted for the connection of an additional panel using EL Nylon Tubing to increase the total capacity of the system.this outlet is blanked off when not required. Weight 4 kg Accessory EL Nylon Tubing 30 metre length. For pressures up to 1700 kpa. Used for connecting Air Compressors to Pneumatic Pressure Reducing Panels, or for connecting two Pressure Reducing Panels together. Weight 2 kg EL kpa Two-way Pneumatic Pressure Reducing Panel 51

9 26 Pressure systems 6-Way Pressure Distribution Panel These six-way systems have been designed to provide low cost panels specifically for the monitoring of up to 6 independent pressures.they are particularly useful for setting up and controlling a 3 cell effective stress system using 3 independent cells and 3 independent back pressures. Two models are available; EL which is used with oil/water systems and EL for use with pneumatic systems. Both panels are used in conjunction with EL Universal Pump and Pressure Indicating Panel which provides pressure monitoring and facilities for filling and de-airing the system. EL Way Water Distribution Panel For Oil/Water Systems Comprising no-volume change valves mounted in housing for controlling up to six independent outlets. Connection ports for coupling to EL are included. Maximum working pressure 1700 kpa. EL Way Pneumatic Pressure Panel comprising six pneumatic control valves mounted in housing for controlling six independant outlets. Supplied with connection ports for coupling panel to EL Maximum inlet pressure 1400 kpa maximum outlet pressure 1000 kpa. Twin-burette Volume Change Unit Fitted with reversing valve and by-pass valve.the unit is fitted with burettes graduated 0 to 100 ml x 0.2 ml and is mounted on a solid panel for wall or bench mounting. EL Twin-burette Volume-change Unit Supplied with 100 ml capacity x 0.2 ml burettes. Weight 8.3 kg Accessories EL System Accessories Red Dye, Kerosene-soluble EL mm Connector with sealing washer EL Nylon Opaque Tubing 6 mm outside diameter x 4 mm inside diameter. For use up to a pressure of 3500 kpa. Priced per metre. EL mm Elbow Connector EL mm T-connector EL Way Water Distribution Panel EL Twin-burette Volume Change Unit 52

10 Pressure systems 26 Oil/Water Constant Pressure System 0 to 1700 kpa (250 lbf/in 2 ) fully variable Continuous constant pressure control One litre capacity The ELE oil/water constant pressure system, PressureTest 1700, is extremely versatile and can be used in conjunction with a wide range of test equipment. The unit provides continuous variable pressure up to 1700 kpa. Pressure is increased or decreased simply by turning a control wheel. The apparatus is supplied without a gauge for those customers who have suitable pressure monitoring equipment. A 200 mm diameter gauge is offered as an accessory. The machine features a clear hydraulic/water interface reservoir and up to one litre capacity of water is available under pressure. EL /01 PressureTest 1700 Dimensions (without gauge) 240 x 400 x 500 mm (l x w x h). Weight 17 kg For V AC, Hz, 1 ph Accessories EL Spares EL EL series Pressure Test 1700 Test Gauge 200 mm diameter, for measuring pressures up to 1700 kpa. Weight 0.6 kg 1700 kpa Pressure Transducer see EL Oil 2 litres for changing the oil in EL and EL series, supplied in plastic container. Weight 2.2 kg Special Note: It is recommended that the oil be changed every 3 months when the unit is in constant use. Modular Pressure Panel System Modular system for flexibility Wall mounting Four outlets 6 mm diameter pipework for quick filling and draining Standard type valves on all units on/off with no volume change Ideal system for geotechnical laboratories The modular concept of this system provides flexibility and cost saving by selecting only those units which are relevant to the particular testing requirements. It is simple to update the system with the addition of other units which can be quickly connected together. The units may be used with a variety of pressure systems such as pneumatic and oil/water and are designed to accept pressures up to 1700 kpa where appropriate. Universal Pump and Pressure Indicating Panel This is the main gauge unit in the system and can be used for monitoring pore pressures and also provides for fine control of pressure within the system using the rotary hand pump.the unit is fitted with a dual calibrated 250 mm diameter pressure gauge, four inlet/outlet no-volume change valves, screw controlled rotary hand pump, water reservoir and isolating valves.the unit is housed in a hinged case for wall or bench mounting. By using an isolating valve the panel may be used to monitor cell or pore pressure. EL Universal Pump and Pressure Indicating Panel with dual calibrated pressure gauge, 1700 kpa and 250 lbf/in 2. Weight 12 kg Spare EL /10 Pressure Gauge 1700 kpa 250 mm diameter. Weight 2.5 kg EL Universal Pump and Pressure Indicating Panel 53