FLEXIBILITY-BASED LINEAR DYNAMIC ANALYSIS OF COMPLEX STRUCTURES WITH CURVED-3D MEMBERS

A flexibility-based formulation of a new mass matrix for the dynamic a nalysis of spatial frames consisting of curved elements with variable cross-sections is presented. The main characteristic of such formulati ons is the exact equilibrium of forces at any interior point, with no additional hypotheses about the distribution of displacements, strains or stresses. Accordingly, the derived element mass matrix takes into account the exact stiffness and mass distribution throughout each elem ent. In validation tests, results obtained with this method are compar ed with those obtained by other numerical or analytical formulations, showing the accuracy of the proposed method. The comparison of experim ental results for a multispan arch bridge subjected to a dynamic load with those achieved by means of the proposed method are finally includ ed to illustrate its efficiency in the treatment of complex structures . (C) 1998 John Wiley & Sons, Ltd.