A three-dimensional isogeometric boundary element analysis in elasto-plasticity

On the basis of some recent works of the authors, a three dimensional (3D) iso-geometric approach is here presented in the boundary-integral-equation-based 3D structural analysis. The domain under investigation presents plastic areas of predefined shape. The geometry of the plastic zone is modeled by the aid of two NURBS surfaces and of a special mapping method. The advantage over currently used methods is that no discretization into cells is required to evaluate the arising volume integrals. Moreover, the geometry independent approximation allows flexible refinement options. The boundary of the domain is also discretised by the use of multi-level NURBS discretization. The nonlinear system of equations is solved by a Newton Raphson scheme. One numerical example is provided with regard to a test case for which a comparison between modified and full Newton Raphson approach is performed.