A two-dimensional inverse crack tip element for shape sensing and structural health monitoring

Abstract

inverse Finite Element Method (iFEM) is a powerful tool for shape sensing and structural health monitoring of marine structures and has several advantages with respect to some other existing approaches. However, current iFEM formulation is not suitable for marine structures having pre-existing cracks due to stress singularities at the crack tip. In this study, a two-dimensional inverse crack tip element formulation is presented. The element is suitable for thin structures under in-plane loading conditions. The inverse crack tip element allows determination of Stress Intensity factor values at the crack tip. To validate the accuracy and demonstrate the capability of the inverse crack tip element, six different numerical cases are considered for different geometry, loading and boundary conditions. iFEM analysis results are compared with regular finite element analysis results as the reference solution and very good agreement is observed between the two solutions demonstrating the capability of the current iFEM approach.