The shape change energy criterion of Iso-σ_θε_θline for mixed mode crack and the application in concrete

摘要

In order to study the concrete compound crack and fracture extension problem such as brittle material, based on the analysis of the fracture criterion theory, on the analysis of some measured data, and the near crack tip portion of the shape change energy, the strain energy criterion of Iso-σ_θε_θline for I -II mixed mode crack was proposed, a crack initiation angle formula and the fracture criterion were established, and the variation law among θ_o, K_(IIc)/K_(Ic) with Poisson ratio was discussed. Using the criterion, the concrete compound crack was analyzed. Results show that the theoretical values are consistent with the measured values. So the criterion can be applied to analyze the mixed mode crack fracture of brittle material such as concrete.