AN ASSUMED STRAIN METHOD FOR ISOGEOMETRIC FINITE ELEMENT MODELING

The isogeometric finite element method based upon the non-uniform rational B-spline has attracted remarkable research attention since this approach gives an excellent integration between the computer-aided geometry design and the finite element analysis. Moreover it is very straightforward to construct higher order smooth NURBS approximation for this method. In this work an assumed strain formulation by using the sub-domain strain smoothing integration is developed for the isogeometric finite element analysis. This method is implemented through the subdivision of an element into several sub-domains where the smoothed strain is constructed in the parametric space for the integration of the internal energy. The derivatives of shape functions are avoided in this formulation. Numerical results demonstrate that the present formulation is very effective and efficient.