Fracture Mechanics Parameters of Fine Grained Concrete with Polypropylene Fibres

Fracture mechanics is widely used to analyze the material behaviour in a structure. The paper reports the results of an experimental programme focused on the effect of various synthetic fibres on the fracture properties of concrete investigated in Mode I conditions. The changes in concrete properties were analysed on the basis of the critical stress intensity factor K-Ic, the critical value of crack tip opening displacement (CTODc) and the fracture energy G(F). The addition of the synthetic fibres had a slight effect on the strength properties of concrete but, at the same time, it had a significant influence on the fracture mechanics parameters by the modification of pre-cracking and particularly post-cracking behaviour of the concrete. Results of measuring the toughness and energy-absorption characteristics showed that the specimens reinforced with synthetic fibres acquired a great ductile behaviour and energy absorption capacity, compared to ordinary concrete specimens. (C) 2016 The Authors. Published by Elsevier Ltd.