Publication: Application of Asymptotic Waveform Evaluation (AWE) In Beam and Truss
Loading...
Date
2004-02
Authors
Lau, Sun Wah
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
There is always a misunderstanding that, when a force is applied on a structure (either beam or truss), the maximum deflection or displacement of the material is that shown in steady state. Actually, these structures will deform more than the displacement during the steady state. This is due to the moment caused by the forces as stated in Newton’s second law of motion (F=ma). Because of this unexpected higher magnitude of displacement, many products have failed to achieve its desirable quality. Micro-scale electronic packaging is a very good example. The wire boding equipment causes excessive deflection on electronic package, and damage the tiny component in the package. Earthquake, an undesirable and unexpected disaster, transferring vibration on bridge trusses. Most of the cases, the impulse force from earth fails the structure of bridge trusses. Therefore, dynamic analysis on structure is essential nowadays. Plenty of analysis procedures has been introduced. Among these methods, Finite element method (FEM) has given an accurate result besides of its flexibility. The FEM is a
numerical method for solving problems of engineering and mathematical physics (Logan, 2001). However, implementation of Finite Element Method (FEM) in structural and other analysis usually will produce a formulation in space/time domain. This kind of space/time domain formulation leads to a set of ordinary differential equation and have to be solved in the time domain. An implementation of AWE scheme in first and second order ordinary differential equation shows a break through as compared with conventional method. This advanced, powerful and efficient scheme shows excellent result in electronic and thermal analysis (Ooi, 2003; Da-Guang Liu, 1995). In this thesis, AWE is pioneered in beam and truss analysis. Steady state response and dynamic response (before steady state) will be considered.