A unified failure criterion for normal, high-strength and steel fibre-reinforced concrete

Abstract

A failure surface is proposed for normal (NC), high strength (HSC) and steel fiber-reinforced concrete (SFRC) under multi-axial loads. A closed-form solution for predicting the state of stress in concrete is also developed. NC and SFRC plates under biaxial loads and cylinders confined by steel tubes were tested. The experimental results obtained through this study and other published literature were used to verify the proposed failure surface. An equation is proposed to predict the strain at failure for SFRC under multi-axial loads, Epsilon(ci). The proposed failure criterion, method for closed-form solution, and equation to predict Epsilon(ci) were incorporated into constitutive models in a Finite Element software. Experiments of NC cubes and SFRC plates under multi-axial loads and beams under 2-point load were modeled to illustrate the application of the failure surface to a wide range of concrete under varying load conditions. Good agreement between analytical and experimental results is observed.