STRUCTURAL DAMAGE IDENTIFICATION VIA MODAL DATA BASED ON GENETIC ALGORITHM

摘要

This paper presents a nondestructive global damage identification method based on the changes in frequencies,mode shapes and flexibilities of vibration of structural system. The method is applied at an element level using a finite element model developed with MATLAB,the damage is represented by a reduction factor of the element bending stiffness and an adaptive genetic algorithms (AGA) is proposed to identify damage location and severity of the structure,which is improved in selection,crossover,mutation and construction of objective function. The method has been verified by a number of damage scenarios for simulated beams,and from the analysis results it can be seen that the proposed AGA yields a suitable damage location and severity identification. The results can be used in the practice of bridge structures for damage detection,health monitoring,bearing capacity evaluation and the application is significant theoretically and practically.