The Pavetest Overlay Tester is a servo-pneumatic controlled testing machine utilizing digital control of a high performance servo valve to provideaccurate loading wave shapes up to 60Hz, specifically designed to determine the susceptibility of asphalt mixtures to cracking according toTexas DOT test procedure Tex-248-F and proposed ASTM Standard WK 26816.
The machine applies cyclic loading to a specimen that is cut from a 150 mm diameter sample into the shape of a rounded end beam. Thesystem comprises a load frame, with one fixed and one moving plate, temperature control system, Control and Data Acquisition System (CDAS)and optional silent air compressor. The specimen is glued to two plates and this assembly is placed in the machine for testing. This is intendedto simulate the action of movement under an asphalt overlay to assess how failure might occur in the field due to factors such as thermalexpansion / contraction and reflective cracking.
The Pavetest Overlay Tester is underpinned by Pavetest’s CDAS digital controller, TestLab software and all the necessary accessories, hardware and software in unison.
Technical Features
• Temperature controller. The overlay tester is fitted with a temperature controller, which controls the heating/cooling provided by the thermo-electric unit fitted to the machine.
• The specimen preparation jig allows allows users to properly locate and glue the specimen on plates. It can accomodate up to threesets of platens. It includes 2 mm teflon strip, which helps aligning the specimen plates and eliminate the need to saw the glue afterwards,and a dead weight.
• The Overlay Tester main unit comes fully assembled.It can be placed on the folding stand supplied, complete with wheels.