抄録
In this paper, we first point out that the finite element interpolation functions sometime lose their linear independencies when the elements are superposed each other in s-Version finite element (s-FEM) analyses. This problem has been known among engineers/researchers who have studied and used the s-FEM for solid mechanics analyses. Once the interpolation functions lose their linear independencies, resulting global stiffness matrix becomes singular and, therefore, the solutions lose their uniqueness. Although it is rare for an analyst to come across such a problem, it degrades the robustness of s-FEM. This paper describes a way to judge the occurrence of such a problem and propose a method to circumvent it.
