A strip yield model for two collinear cracks

In this paper two alternative approaches for analysing the non-linear interaction between two equal-length collinear cracks subjected to remote tensile stress on infinity are developed. The approaches are based on the classical Dugdale strip yield model and utilise the distributed dislocation formulation to represent two through-the-thickness cracks in an infinite plate. In the first approach the solution is obtained analytically by solving Föppl integral equation; in the second a numerical procedure based on the Gauss–Chebyshev quadrature method is applied. The latter approach can be extended to other multi-crack problems or more complicated types of loading. The developed approaches are validated against previously published studies and new results for crack tip opening displacement are presented.