FORMULATION OF GEOMETRICALLY NONLINEAR PROBLEMS IN THE SPATIAL REFERENCE FRAME

This paper presents a new formulation for geometrically non-linear pro blems and their numerical treatment by the p-version of the finite ele ment method. The formulation is characterized by a weak form based on the spatial representation of the equilibrium equations, a deformed ge ometry mapped by the displacement field, a natural description for non -conservative loads that keeps the symmetry of the equations, and a di rect (non-incremental) iterative algorithm to solve the equations. The paper is concerned only with problems for which the solution is uniqu e, i.e. the load-displacement curves are single-valued, and the strain s are small. Examples are presented. (C) 1997 by John Wiley & Sons, Lt d.