nurbs-based isogeometric analysis method application to mixed-mode computational fracture mechanics

An interaction integral method for evaluating mixed-mode stress intensity factors (sifs) for two dimensional crack problems using nurbs-based isogeometric analysis method is investigated. the interaction integral method is based on the path independent j-integral. by introducing a known auxiliary field solution, the mixed-mode sifs are calculated simultaneously. among features of b-spline basis functions, the possibility of enhancing a b-spline basis with discontinuities by means of knot insertion makes isogeometric analysis method a suitable candidate for modelling discrete cracks. moreover, the repetition of two different control points between two patches can create a discontinuity and also demonstrates a singularity in the stiffness matrix. in the case of a pre-defined interface, non-uniform rational b-splines are used to obtain an efficient discretization. various numerical simulations for edge and center cracks demonstrate the suitability of the isogeometric analysis approach to fracture mechanics.