Dynamic Characteristics of Core Wall Structures Subjected to Torsion and Bending

A general method using the theory of thin walled structures is given for determining the natural frequencies and mode shape of core wall structures having closed or open section, subjected to torsion and bending using a finite element approach. Consistent mass matrices related to torsion and bi-moment effects have been derived using shape functions corresponding to (a) the static deflection configuration and (b) an assumed polynomial deflection configuration. The stiffness matrix developed on the basis of the proposed theory includes warping deformations and its use with the finite element method enables the possible changes in the storey segments to be fully represented, such as the thickness of the wall and the cross-sectional characteristics.

D.V. Mallick and R. Dungar