ISOGEOMETRIC STRUCTURAL ANALYSIS BASED ON NURBS SHAPE FUNCTIONS

Abstract

Finite element method (FEM) is a tool that is mostly used for the structural analysis. The method is based upon approximation of the actual geometry and displacement field of the structure over the finite element domain. In practice, Lagrange polynomials are mostly used as shape functions (approximate functions). They provide only the C0-continuity at the element boundaries. This paper elucidates a possible approach based on the so-called isogeometric analysis to improve this property. The isogeometric FEM analysis applies the same functions to describe the CAD model, the element geometry and the element displacements. The paper represents developed algorithm and the obtained results for a relatively simple test case.