Determining of three collinear cracks opening displacement using the process zone model

The general failure of structures is often preceded by the growth and coalescence of intermediate cracks. In this work, a model with process zone is used to study the deformed state of an infinite isotropic body with three collinear cracks. A numerical algorithm is presented to obtain crack opening displacements effectively. The problem is analyzed for all possible cases of mutual location of the cracks and different levels of loading. The numerical solution shows negligible influence of two cracks coalescence process on the opening displacement of the third crack. An example of the results implementation to calculate crack initiation duration in a problem for viscoelastic body is given.