A contour integral method to compute the generalized stress intensity factor in complete contacts under sliding conditions

In complete contact fretting problems under global sliding conditions, the stress state at the corner of the contact zone is usually singular (assuming elastic behaviour). This stress state is characterized by two parameters: the order of singularity and the generalized stress intensity factor (GSIF). The former can be analytically calculated for a given problem. However, the GSIF is usually obtained by means of numerical procedures. One of the most used is the application of the stress extrapolation technique in combination with a FE analysis. In this work, a path-independent contour integral is defined which enables the GSIF calculation. Using this novel technique, a much more accurate estimation of the GSIF is obtained for a given discretization. In addition, a refined mesh around the singular point is not needed, because the contour integral can be applied along paths far from the singularity dominated zone due to its path independence.