A BASIC FLAT FACET FINITE-ELEMENT FOR THE ANALYSIS OF GENERAL SHELLS

A triangular flat facet finite element for the analysis of general thi n shells is presented. It is constructed from simple cubic polynomial displacement fields using a complete set of six degrees of freedom at the element vertices, thereby easily meeting the requirements of stand ard commercial computer programs. The theoretical development is based on a variational principle which allows a direct formulation of the e lement stiffness matrix, without inversion, and which permits consider able simplification of the mathematical formulation. The new flat face t element generally produces more accurate numerical results than thos e obtained in earlier related work. It also offers a possible basis fo r constructing an improved curved approximation to a shell surface and for further developments in connection with applications involving ge ometric non-linearity.