Guided waves in thin-walled structural members
Loading...
Files
Date
1999-04-01T00:00:00Z
Authors
Rogers, John B. C.
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Many common structural members can be thought of as an assemblage of thin plates. For example, an I shaped cross-section can be made from three or five thin plates and an angle can be thought of as two thin: plates whose sides are rigidly attached at an angle, and so on. In this study a multi-purpose computer program was developed, based on a Rayleigh-Ritz (RR) type stiffness approximation, to investigate the wave propagation in infinitely long thin-walled members and the free vibration of thin-walled members that are simply sup orted at their ends. Also, wave propagation characteristics of these members where studied. To model the behaviour of these types of structural members, using a finite element methodology, an element that closely models the behaviour of a thin plate was created. There are two uncoupled motions of a homogeneous thin plate having material symmetry about its middle surface; one corresponds to inplane motion and the other to bending. Previous studies used a three node parabolic element to model the inplane motion of the plate. In the present work, the three node inplane element and a two node beam element were used to generate an element which models both the inplane and bending motions of a thin plate. The program was checked for accuracy against another approximate solutions as well as analytical solutions. The Rayleigh-Ritz approximation proved to be effective in calculating the wave dispersion characteristics (wavenumber and modeshapes for a given frequency) of thin-walled, infinitely long members as well as the characteristic frequencies of vibration of simply supported thin-walled structural members.