Tsugumichi Watanabe

Interfacial Fracture Mechanics Approach to Delamination Resistance between Cement-Based Materials

In this paper, a new method capable of predicting the critical deformation of composite materials with interfacial cracks is presented under mixed mode conditions using stress intensity factors K1 and K2 and the fracture criteria of the interface between concrete and cement-based wet finishing are evaluated. Two types of stress intensity factors are considered on the basis of the interfacial fracture mechanics. The stress distribution and singularity of the interface between dissimilar materials are obtained by two-dimensional elastostatic boundary element analyses under a plane strain state. Two types of stress intensity factors determine the mixed mode fracture criteria of the interfaces. Prediction of the first delamination and its development by these factors are compared with the empirical results of compressive tests on composite model specimens containing several types of finishing. It was confirmed that critical deformation could generally be predicted by the present method.