Effect of specimen size on fracture energy and softening curve of concrete: Part I. Experiments and fracture energy

The fracture energy of concrete G(F) is a fundamental fracture parameter, presenting the concrete's cracking resistance. However, because of the experimentally observed size dependency, it remains controversial as to whether the fracture energy can be considered as a material property. In this study, a three-point bend test for a notched beam and a wedge splitting test were performed with different size specimens for ten different concrete mixes in order to investigate the effect of specimen size and geometry on the fracture energy. A data processing method was proposed for averaging the test results of companion specimens, and the fracture energy was calculated from the averaged results. From a comparison of the fracture energies, it was found that the fracture energy increases with an increase in specimen size in both the beam and wedge splitting tests. (C) 2008 Elsevier Ltd. All rights reserved.