XFEM with global enrichment for 3D cracks

We present an extended finite element method (XFEM) based on fixed area enrichment which 1) suppresses the difficulties associated with ill-conditioning, even for "large" enrichment radii; 2) requires 50 times fewer enriched degrees of freedom (for a typical mesh) as the standard XFEM with geometrical enrichment (for the same or better accuracy level); 3) increases the accuracy level of the stress intensity factors and leads to "smooth" stress intensity variations along the crack front