Comparison of fracture parameters obtained from modified semi-circular bending (SCB) test

Abstract

For several years the crack propagation test data of asphalt mixtures according to CSN EN 12697-44 have been collected and evaluated at the Czech Technical University in Prague. Over time, the standardised test procedure has been adapted to better suit the conditions and practice typical of the Czech Republic – in terms of test specimen compaction, availability of cutting discs of suitable thickness, diameter of test specimens, loading speed etc. Modifications encompassed some of the test conditions as well as the procedures of data logging and subsequent evaluation of raw data. It has also been gradually established that the strict focus on fracture toughness, assumed by the European standard to be used as the only suitable qualitative parameter, is probably incorrect, or at least ineffective. The characteristics of fracture energy have been introduced and further studied.