Abstract

Rapid progress in the analysis and construction of high-nonlinearity structures has been made over the last three decades. The use of a new method is necessary to accuracy and stability to improve performance of this structure. The Fletcher-Reeves method belongs to a group of methods called conjugate gradient methods which attempt to locate a local minimum function. The approach of the proposed method was based upon the principle of conservation of energy. All nonlinear effects due to material properties, large displacements or local failure can be incorporated in the nonlinear dynamic analysis. Fletcher-Reeves algorithm was applied to calculate the set of displacements to minimize the energy of structural system. In this paper, a theory for nonlinear dynamics response analysis of high nonlinearity structure was developed based on the minimization of the total potential dynamic work.

Key words: Fletcher-Reeves method, optimization of energy, finite element method, perturbation technique, analyzing modal, nonlinear dynamic response.