Study On Damage Identification Of Structures Based On Principal Component Analysis

With decades of development, bridge damage identification study has been made alot of substantive progress. Especially in recent years, with the rapid development ofcomputer technology as well as signal analysis and signal acquisition technology,bridge damage identification has entered a new phase. With the advantage of usingwidely, high efficiency and high practical value, damage identification that based on thestructural vibration won the favor of many scholars.In this dissertation, some common dynamic identification method is introduced to us.And the author makes a brief evaluation of these methods. Then, the author proposed amethod that use frequency response function as the characteristic parameters of thestructure, this method has a very obvious advantage. This topic use Frequency responsefunction as the characteristic parameters, and combine principal component analysis andprocess control of principle to study the damage identification of T-beam model in thelaboratory.In this dissertation, the author build the original matrix use the imaginary frequencycurve data of the frequency response function curves, and use the difference matrix ofthe original matrix which come from the state of integrity structural and damagestructural. The damage matrix that is the basis to obtain the structural characteristics ofinformation damage identification matrix has numerous dimensions, and it contains alot of overlapping information. So, in order to facilitate the calculation and find out themain contradiction of the problem, this article use principal component analysis (PCA)of multivariate analysis to compression damage matrix and reduce the dimension of thedamage matrix. And, we get the first several order principal components from thedamage identification matrix. And then, with the help of process control charts, bridgedamage elements can be oriented successfully. Conclusion: this method can effectivelydiscern whether there is injury of the structure and identify the location of structuraldamage.The author also research of signal acquisition, pilot program and test operation,accumulating wealth experience of damage identification.