EXPLORATION ON SHEAR BEAM METHOD FOR NATURAL FREQUENCY OF LAYERED SITE NEARBY THE GROUND FISSURE

To explore the analysis mothed of natural frequency for the site closing to ground fissure, the recursion formula and implicit analytic solution of single and random multi-layer site were derived based on the traditional shear beam model with the assumption of horizontal displacement continuity. In comparison with the solution of normal site, the fundamental frequency of hanging side site is smaller than normal site's and the heading side site is inverse. Furthermore, the fundamental frequency of hanging and heading side site will close the solution of normal site with the increase of the calculating width. If the order of natural frequency enhance, the solution in this paper will more and more closing the normal site solution. The solution indicate that the implicit analytic solution of closing ground fissure site resented by this paper is reasonable.