Fracture parameters for high-performance concrete

This paper reports and discusses the results of an experimental investigation on fracture properties of high-performance concrete, involving the tests of 115 three-point bend specimens with different compression strengths. The parameters were obtained by the work-of-fracture method and by the size effect method. For most series of tests the fracture energy was measured by the two methods, allowing a correlation between the values obtained by the two processes. A comparison with some results found in literature was performed. It was found that: (a) the ratio between the fracture energy measured by the work-of-fracture method (GF) and by the size effect method (Gf) matched the value estimated by other researchers (GF/Gf ≈ 2.5); (b) generally, GF increases as the concrete compressive strength increases; and (c) the values obtained for Gf showed a slight trend to decrease with increasing compressive strength. The results obtained from the standard compressive strength tests indicate that the concrete strength was limited by the type and size of the coarse aggregate. The objective of this study is to provide some experimental data that can be useful in engineering practice for calibrating numerical constitutive models.