Dynamic analysis of trusses including the effect of local modes

The dynamic analysis of trusses using the finite element method tends to ov erlook the effect of local member dynamic behavior on the overall response of the complete structure. This is due to the fact that the lateral inertia s of the members are omitted from the global inertia terms in the structure mass matrix. In this paper a condensed dynamic stiffness matrix is formula ted and used to calculate the exact dynamic properties of trusses without t he need to increase the model size. In the examples the limitations of curr ent solutions are presented together with the exact results obtained from t he proposed method.