The Vibration of Frames

Abstract

A method is presented of calculating the natural frequencies of plane frames. The technique is a numerical one and is based upon tables which were presented by the author (Bishop 1955)† in a recent article. The present paper is a sequel to the previous one and illustrates a way of using the data given in it. The frequency calculations are not restricted to the fundamental and they are such that a given frame may be checked for possible resonances over a prescribed frequency range without calculation of all lower natural frequencies. When a natural frequency has been found the appropriate principal mode may be calculated. The natural frequencies of the systems which are used for the purposes of explanation were checked experimentally.