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

 For more information visit: .uk/shop/asphalt-testing/servo-pneumatic-universal-testing-machine/