Indirect tensile test on cylindrical-shaped specimens

3 Indirect tensile test on cylindrical-shaped specimens 

This test method determines the asphalt behaviour under repeated load fatigue testing with a constant load mode using an indirect tensile load. 

The specimens are of cylindrical shape and prepared in the laboratory, drilled from laboratory-prepared slabs or prepared from drilled core taken from the road (pavement). The compaction of specimens in the laboratory is carried out using a gyratory compactor according to CEN EN 12697-31 (2007). If the specimens are drilled from laboratory slabs or prepared from cores taken from the road, their preparation is conducted according to CEN EN 12697-33 (2007) and CEN EN 12697-27 (2000), respectively. 

The cylindrical specimens for asphalts with maximum aggregate size up to 25 mm have a diameter of 100 mm and a thickness of at least 40 mm. If the maximum aggregate size is higher, up to 38 mm, the specimens have a diameter of 150 mm and a thickness of at least 60 mm. 

The test is carried out with at least three specimens per stress level, for laboratory-manufactured specimens, or at least five specimens, for cores from the road. The specimens after ageing are conditioned to the specified test temperature for at least 4 h prior to testing. The test temperature is usually 20°C, 15°C or 10°C. 

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