The calculation of the stress intensity factors (SIFs) is based on the work of Nikishkov and Atluri (1987)
, who proposed an equivalent domain integral method for calculating the fracture parameter SIF of a 3D arbitrary crack. This method has been widely used in standard FEM and in this subsection it has been introduced into the CB shell element of X-FEM.
A local coordinate system (x1
) is established at the crack tip as illustrated in Figure 6.17
, where x1
is located on the crack surface perpendicular to the crack ...