A path‐independent domain integral to characterize fatigue crack propagation by cyclic material forces

A lot of structures undergoing cyclic loading fail at load values smaller than their ultimate design loads. In the framework fracture mechanics, crack propagation process can be separated into three different stages. first stage, micro-cracks propagate and form together a macro-crack. The macro-crack propagates stably in second which is also known as PARIS' regime. third unstably leading to failure structure. pioneering law characterizing stable growth law. aforementioned correlates rate stress intensity factor. Unfortunately, factor limited cases where theory linear elastic mechanics applicable. To overcome limitations factor, domain-integrals evaluated by configurational forces or material are used fatigue criterion. However, path-dependent. aim study hand derive path-independent domain integral characterize elastic-plastic viscoelastic solids small strains. First all, derived using free energy. Furthermore, path-independence approach illustrated numerical examples. Finally, force validated comparing it experimental results.