An economic accurate beam testing system which facilitates the rapid throughput of modulus and fatigue tests.

Bending tests are widely used for measuring the stiffness modulus and assessing the fatigue resistance of asphaltic paving materials. Four point bending tests are included in CEN, AASHTO and Chinese test specifications. The specimen is a prismatic beam which is subjected to sinusoidal loading in either the controlled strain or controlled stress modes.

The Stand Alone Four Point Bending Beam machine CRT–SA4PT–BB uses advanced servo pneumatic technology and a high-speed digital data acquisition and control system together with user–friendly software. During testing both graphical and tabular data are displayed on screen and test data is stored to disc in Microsoft Excel^TM compatible format. The clamps are at 118.5 mm centres (the distance between the outer clamps is 335.6 mm (14 inches) according to AASHTO specifications² but the height and width of the beam can be varied.

2 tests on beams containing aggregates greater than 20mm are not strictly in accordance with annex D of EN 12697-24 which states that this non-compliance should be explicitly mentioned in the test report.

  Key Uses:

• Mix design
• End product specification
• Assessment of new materials

• EN 12697–24 Annex D
• EN 12697–26 Annex B
• AASHTO T321–03 (TP8)

• Frequency range 0.1 to 30Hz (1)
• Low cost pneumatic stand alone four point bending machine
• Utilises a low–friction actuator and high performance ceramic spool servo-valve
• On-specimen measurement system removes errors due to freame flexure
• Accepts AASHTO beam sizes
• Sinusoidal controlled strain or controlled stress fatigue test modes
• Constant torque motorized specimen clamping to eliminate errors due to localised beam indentation
• Self-contained loading system
• User friendlysoftware for determination of fatigue resistance and stiffness modulus
• Constant torque motorized specimen clamping removes errors due to localised beam indentation.

• User friendly, intuitive and reliable Windows^TM software developed using LabVIEW^TM
• Specifically written to meet EN 12697–24 Annex D and EN 12697–26 Annex B
• The user interface can be translated into the user's preferred language – please enquire
• Stored test data can be analysed and compared with other test data utilising a spreadsheet package
• Utilities are included for curve fitting of acquired data; testing of system's inputs and outputs; phase correction and a transducer database for storing calibration factors.

• 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.