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™ compatible format. The clamps are at 118.5mm centres (the distance between the outer clamps is 335.6mm (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.