A comparative study on three approaches to investigate the size independent fracture energy of concrete

•Investigation on size-independent fracture energy (GF) of concrete.•GF prediction through bilinear model and energy release rate.•Proposed method based on Gf averaging for assessment of GF.•Comparative estimated of GF from three different methodologies.

This paper deals with investigation of size-independent fracture energy (GF) of concrete. The study involves numerical modeling of three point bend concrete beams that are geometrically similar having constant length to depth ratio with varying notch to depth ratios. RILEM fracture energy (Gf) values evaluated numerically and experimentally are found to be in reasonable agreement. GF is estimated from developed relationship of fracture energy release rate and through bilinear model by Gf values. Gf values have been utilized to develop a simple methodology for estimation of GF. Comparative analysis of GF from three different methodologies has been carried out.