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The Nottingham Asphalt Tester (NAT) - Servo-Pneumatic Universal Testing Machine


  • 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 Materias: AASHTO T307 (previously TP46); NCHRP 1-28A
  • NATs have become essential to laboratories, universities, oil companies, regional laboratories, contractors and consulting engineers, worldwide. Trials have demonstrated that NAT test results give excellent correlation with other test methods such as bending beam and wheel tracking.

    The NAT provides the most inexpensive and userfriendly means of measuring and assessing the mechanical properties of asphaltic paving materials on a routine basis. It is designed to derive the maximum information about a material using either cores cut from the highway or laboratory moulded specimens.

    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; EN12697-25, 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 andAASHTO 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


    • 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


    • 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


    Maximum Load Electronically limited to 15.5kN
    Load Transducer ±20kN
    Actuator Stroke mm 30
    Frequency Hz 0 to 30
    Electrical Supply¹ 220-240 Volts 50 Hz @ 13A
    Compressed Air 7-10 bar at 600 L/min
    Dimension mm (WxDxH) Frame 360 x 400 x 740
    Control Box 360 x 280 x 140
    Working space required mm(WxDxH) 825 x 1650 x 2100 when fitted in cabinet CRT-TCC
    Estimated Weight Kg Frame 30
    Control box 6
    PC Included

    ¹ others available upon request

    Calibration & Maintenance

    Calibration, Annual Service and Maintenance Contracts are available for this device. UKAS accreditation to satisfy typed testing as described in EN 13108. Please enquire for further details. Note: This device should be checked and calibrated annually.


    See also:
    Universal Servo-Pneumatic Test System
    Universal Servo-Hydraulic Test System
    Four point beam fatigue test
    The Wheel tracker
    Hamburg Wheel tracker
    Wheel tracker EN12697-22 Large device CRT-WTENLD
    Roller Compactor
    Large device EN roller compactor