Fracture toughness of concrete with basalt fiber

Abstract

The analysis of fracture mechanics parameters of concrete with new types of fibers is essential for the dissemination of their application and development of new methods of structural design.Fracture mechanics parameters are widely used to analyze the material behaviour and also in the design process of selected structures. The paper reports the results of an experimental programme focused on the effect of non-metallic (basalt) fibers 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 (CTOD c ) and the fracture energy G F . The addition of the basalt fibers had a slight effect on the strength properties of concrete but, at the same time, it had a significant influence on the fracture 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 basalt fibers acquired a great ductile behaviour and energy absorption capacity, compared to ordinary concrete specimens.