MIXED-MODE FRACTURE ANALYSIS IN HIGH-PERFORMANCE CONCRETE USING A BRAZILIAN DISC TEST

This paper reports and discusses the results of an experimental investigation into the fracture mechanical properties of high-performance concrete (HPC) with a compressive strength higher than 100 MPa. In total, 6 specimens for a three-point bending test and 12 specimens of a Brazilian disc under a mixed-mode load were included in the experimental measurements. The fracture toughness was evaluated for mode I in the case of a three-point bend test and a Brazilian disc test, allowing a correlation between two geometrically different specimens. The fracture resistance under mixed mode I/II was analysed using the Brazilian disc test specimen with a central notch. To evaluate the fracture resistance under the mixed mode a generalised maximum tangential stress criterion was employed and the value of the critical distance r(c) is discussed as an appropriate HPC material characteristic. The last objective of this study was to provide some experimental data that can be useful in engineering practice for calibrating numerical constitutive models.