STATISTICAL DAMAGE DETECTION BASED ON DYNAMIC CHARACTERISTICS OF FEEDBACK CONTROLLED STRUCTURE

A statistical method using dynamic characteristics of structures under control is proposed for detecting small damages. In the study, feedback control based on independent modal space control is used to assign the pole of the system intentionally. A damage indicator consisting of eigenvalues of the close-loop systems with and without damages is proposed and utilized to constitute the statistical quantity. Therefore, hypothesis test method is employed to identify the occurrence of damages. Simulation results obtained from a three-span continuous beam and a Benchmark structure show that the sensitivity of the damage indicator can be enhanced greatly by using the proposed method. The proposed damage detection method is capable of detecting the occurrence of small damage of structures with lower signal-to-noise ratio.