Analysis Of The Dynamics Of Elastic Structures By The Finite Element Method

The finite element displacement method has been used to investigate the transient response and dispersive behavior of elastic structures. An improved technique for integrating the finite element equation of motion has been developed. The stability characteristics of the algorithm have been determined and the critical time step length has been evaluated. A finite element formulation has been derived to study the dispersive characteristics of elastic waveguides. Several new finite elements, which include the wavenumber as a parameter, have been formulated. Dispersion curves for the circular rod, the square bar, and an equilateral triangle waveguide have been obtained. The versatility of the method has been illustrated by obtaining the longitudinal mode spectrum for a unidirectional fiber reinforced composite. The new finite time step algorithm was used to study the response of a finite length fixed-free circular rod to a step pressure applied at the free end. (Author).