RECENT PROGRESS IN NONLINEAR FEM-BASED SENSITIVITY ANALYSIS

This paper reviews the recent progress in sensitivity analysis applied to the nonlinear finite element method (FEM), The sensitivity analysi s method has been successfully developed over the years as a convenien t tool for use in linear FEM, and it is reasonable to say that today t he framework of the methodology is nearly completed, Nonlinear FEM-bas ed sensitivity analysis, however, has only received considerable resea rch attention since the mid 80's, Regarding static nonlinear problems, path-dependent problems such as elastic-plastic problems have been in vestigated by a number of research groups, and several competitive met hods exist, Sensitivity analysis is also practically important in nonl inear buckling and postbuckling problems, for which several methods ha ve been proposed, The performance of the proposed methods in static an d buckling/postbuckling problems are compared, and some numerical exam ples are introduced to clarify the characteristics of the sensitivity which are peculiar to nonlinear problems.