Fracture mechanics parameters influencing the mechanical properties of high-performance concrete

Recently, the study and assessment of the fracture parameters influencing the concrete behavior has emerged as an important research field, especially, in the context of the development of high performance concrete. Deformation and failure behavior of the concrete are affected by the fracture properties of the constituent materials and the properties of the interfaces between these constituent materials. In this paper, for concrete modelled as a two-phase composite, consisting of mortar with aggregate inclusions, fracture mechanics parameters influencing the properties of high performance concrete are assessed. These include elastic moduli mismatch parameters between the mortar and the aggregate and the ratios of the interface fracture toughness to the fracture toughness of the aggregate or that of the mortar. From the tests on novel physical models the roles of these parameters on the mechanical behavior of the concrete are studied. On the basis of the established parameters, preliminary guidelines are proposed to manufacture high performance concrete composites with improved mechanical properties.