Abstract
This paper proposes a new displacement function taking account of axial shortening of elements due to bending. One dimensional combined nonlinear finite element method is formulated using the new displacement function. This method is a modified version of the original FERT (Finite Element method with Rigid-body-motion coordinates and Transfer matrix technique, see for Ref. 15), and will be called FERT-B. Several examples are shown for geometrically nonlinear analysis and for combined nonlinear analysis. The following conclusions for the FERT-B have been derived : (1) Introducing flexural shortening coupling terms into displacement functions remarkably improves the numerical efficiency of geometrically nonlinear analysis. (2) The FERT-B is also available for the combined nonlinear analysis without any modification. (3) The number of variables in computer program for the FERT-B is perfectly equal to that for the original FERT.
