What information can be provided by the asphalt crack propagation test done on semicylindric specimens?

For several years, the crack propagation test data of bituminous mixtures according to CSN EN 12697-44 have been collected and evaluated at CTU in Prague. Over the time the standardized test procedure was adapted to the conditions more suitable to be used mainly in the Czech Republic - in terms of compaction of test specimens, the availability of cutting discs, diameters of test specimens etc. Some of the other test conditions were adapted as well as the procedures of collecting and evaluating the test data. Step by step, it has also been identified that the strict European focus on the fracture toughness as a suitable qualitative parameter is probably not correct. The characteristics of the fracture energy have been introduced and further study is devoted to the use of the tangent direction of force-strain diagrams. Selected findings from the testing of HMAC 22 are summarized in the paper.