This machine is a development of the NAT which was developed by Keith Cooper and Professor Steven Brown at the University of Nottingham. The use of a high precision servo-pneumatic valve in conjunction with a low-friction actuator and sophisticated data acquisition and control, results in a performance that is equal to many servo-hydraulic systems.
Accurate, digitally generated waveforms are applied by the actuator producing repeatable stress variations in test specimens that are simulative of those in a road pavement due to moving traffic. The actuator is double-acting allowing both compressive and tensile forces to be applied. A triaxial cell system is available for the measurement of the resilient modulus of unbound materials.
Standards
Modulus:
- EN 12697-26 Annex C
- EN 12697-26 Annex D & E
- ASTM D7369
- ASTM D4123
- ASTM D3497
- AASHTO TP31
- AASHTO TP62 / TP79
Permanent Deformation:
- EN 12697-25 Methods A & B
Fatigue:
- EN 12697-24 Annex E
- ASTM D7313 DCT (Disc shaped compact tension test)
- EN 12697-44 SCB (Semi circular bending test)
Simple Performance Tests:
- Flow number
- Flow time
- NCHRP9-19; NCHRP9-29
Unbound Materials:
- AASHTO T307 (previously TP46)
- NCHRP 1-28A
Key Features
- Low cost dynamic loading universal test system ideally suited to testing asphalt and unbound granular materials
- Double acting low friction actuator with integral stroke transducer
- Utilises high performance ceramic spool servo-valve
- High quality stainless steel frame
- Issued with UKAS accredited certificate of calibration for EN 12697-24; EN 12697-25, EN 12697-26
- Accessories available to perform a range of standard and non standard test methods
- Can be supplied with standard software to perform EN, ASTM and AASHTO test methods and universal software with which to design non standard test routines
Key Uses
- Assessment of resistance to permanent deformation (rutting)
- Measurement of stiffness modulus
- Assessment of resistance to fatigue cracking
- Resilient modulus of unbound materials
- Mix design
cDAC – Advanced Data Acquisition System
- 20 bit resolution, 5kHz per channel
- Will accept any voltage transducer in any channel using TEDS Thermocouples
- 1024 data points per cycle
- Up to 16 digital input & output channels
- Ethernet/USB/RS232 to PC communication
Software
- User friendly, intuitive and reliable Windows software developed using LabVIEW
- Standard test software available to meet specific EN, ASTM and AASHTO test methods
- Universal test software for the development of test methods using static, sinusoidal, haversine, square, triangular with user selected frequencies and data collection rates
- Stored test data can be imported into a spreadsheet package to be analysed by the user
- Utilities are included for transducer check, diagnostic routines and calibration
For more information visit: .uk/shop/asphalt-testing/servo-pneumatic-universal-testing-machine/
