Structural Damage Detection Using Optimization Method

Asgharvand, Alireza (2017) Structural Damage Detection Using Optimization Method. Masters thesis, University of Mohaghegh Ardabili.

Preview

Text (شناسایی آسیب سازه با استفاده از الگوریتم بهینه سازی) Alireza Asgharvand.pdf Download (897kB) | Preview

Abstract

Early detection of damage can prevent catastrophic breakdown in structures. By timely detection of damage and action to fix its defects, it increases the useful life if the structure. One of the important method of structural health monitoring is vibration method. Given that the dynamic properties of the structure, including the natural frequency and mode shapes, are the function of its physical properties. Therefore, the change in the physical properties of the structure leads to variations in its vibrational properties. In this essay, two effective methods for identifying damage in engineering structures are resented. In the first method, the objective function is implemented based on the modal strain energy(MSE). In the second method. The objective function based on the mode shapes and with the help of the mode Assurance Criterion(MAC) is examined. These methods are ased on minimizing target functions, which results in modifications to the model to behave similar to the actual damaged structure. Also, in this research, assumed damage in the members is modeled by reducing the stiffness of the relevant element the algorithm particle Swarm optimization and Imperialist competitive Algorithm are used to solve the optimization problem. In order to perform the proposed methods, three different structure, including a two- dimensional truss, a three- span three- story two- dimensional frame, three dimensional three- story frame under different injury scenarios, it has been evaluated. The results indicate the ability of methods to identify the damage. It can also be concluded that the MAC method has a high degree of damage detection compared to the modal strain energy method in 3D frame structure. Particle Swarm Optimization and Imperialist competitive Algorithms determine the optimal answers with high precision. Keyword: Particle Swarm Optimization Algorithms, Imperialist Competitive Algorithms, Modal Strain Energy, Mode Assurance Criterion, Structural Health Monitoring.

Actions (login required)

View Item