Subscale enrichment of discontinuity for XFEM crack tip element
Konferensbidrag (offentliggjort, men ej förlagsutgivet), 2013
In the present contribution, we propose a new
XFEM based enrichment of the displacement
field to allow for cracks that end or kink within
an element. The basic concept relies on the
fact that the crack tip element is treated on
a subscale, where, in addition to the macroscopic
continuous and discontinuous displacement
fields, a discontinuous fluctuation field with Dirichlet boundary conditions is introduced
to allow for proper representation of
the discontinuous kinematics. In fact, this results
in a non-standard interpolation of the
discontinuity field, where additional internal
nodes are utilised for the interpolation.
Based on that the internal field vanish along
the the crack tip element edges, it be implicitly solved for in terms of the macroscopic field.
The current methodology is applied to ductile
crack propagation in shells loaded at high
strain rates to allow for not only crack segment through
the entire shell elements (edge to edge).