Department of Civil Engineering,Iran University of Science and Technology
In this paper, the graph models of planar frame structures with dierent symmetries are
decomposed and appropriate processes are designed for their healing in order to form the corresponding
factors. The eigenvalues and eigenvectors of the entire structure are then obtained by evaluating those
of its factors. The methods developed in this article simplify calculation of the natural frequencies and
natural modes of the planar frames with dierent types of symmetry.