ABSTRACT
Linear-elastic theory of fracture mechanics was reviewed and a proposed method for designing structural elements subjected principally to tension presented, based on the strain-energy-release-rate for the fibrous concrete mixes. Eighteen experimental models were provided and of which seventeen were tested and reported including the load ranges and associated circumferential strains upto failure of the experimental hollow cylindrical models. Test results and theoretical values are found to be in good agreement within the scope of the investigation, It is concluded that inclusion of steel fibres in the concrete mixes does not necessarily affect the cracking and crack propagation. It is also concluded that for a specific fibre diameter, using a higher aspect ratio for the given fibre favours failure of specimen by fibre fracture rather than pull-out. Decrease in the strain energy release rate is obtained and the economics of fibre concrete mixes was appraised without recourse to financial consideration.