STUDY ON OPTIMUM STRUCTURAL DESIGN PROBLEMS IN DYNAMIC RESPONSE.

In this study, two general methods of optimum structural designs in dynamic response are newly presented and the validity and effectiveness of the methods are revealed by several numerical examples. After discretizing the objective structural system by a certain method of discretization (for example, finite elements method), the two proposed methods consist respectively of the following combined algorithms: (1) method I, (a) dynamic response analysis - step-by-step integration, (b) optimization procedure - any optimization technique by use of gradients; (2) method II, (a) dynamic response analysis - modal analysis (mode-superposition procedure), (b) optimization procedure - any optimization techique by use of gradients. Emphasis is put on convenient computation procedures of gradients of response quantities (displacement, velocity, acceleration, stress, strain, etc. ) with respect to design variables.