Three-Parameter Failure Criterion for Concrete

A general, three-dimensional failure criterion for plain concrete and mortar is proposed. This criterion is formulated in terms of the first and the third stress invariants of the stress tensor, and it involves only three independent material parameters. Although these parameters interact with one another, each parameter corresponds to each of three failure characteristics of concrete behavior. These material parameters may be determined from simple tests such as uniaxial compression and triaxial compression or biaxial tests. For the purpose of including reasonable values of tensile strengths in the failure criterion, it is advisable to include the uniaxial tensile strength in the parameter determination. A simple expression for evaluation of the uniaxial tensile strength on the basis of the uniaxial compressive strength is given. Twenty-two sets of good quality data for concrete and mortar have been included in this study, and comparisons between the proposed failure criterion and the experimental data are made in biaxial, triaxial, octahedral, and τ - σ planes. The ability of this criterion to capture the characteristics of failure in concrete and mortar appears to be quite good with accuracies generally within the natural scatter of the test data.