Instability Analysis of Viscoelastic Plates Using Boundary Element Analysis

A realistic stability analysis of a specific structural member should consider its function in relation to the rest of the structure as a whole, the loading history and the material behaviour. The deformation response of many materials depends to varying degrees on time-dependent as well as time-independent processes. While common structural materials such as steel or aluminium alloys are essentially elastic at room temperature, at higher temperatures approaching half their melting point, they will manifest viscoelastic behaviour.

On the other hand, polymeric materials are viscoelastic at room temperature with their response being also sensitive to hygothermal environments. Stability analysis of members with such time-dependent material behaviour can be relatively complicated, especially in case of problems with complicated boundary conditions, in which case resorting to numerical techniques often is unavoidable. BEM has been well established as a valid, efficient and versatile numerical method for the stability analysis of elastic structures. However, the application of this method to the stability analysis of viscoelastic structures was a novel idea. As the main objective of this study, the stability of viscoelastic structures under mechanical and hygothermal loading was investigated, using BEM. In this regard, particular emphasis is given to thin plate structures.