The Model Experimental Study Of The Cable-stayed Bridge Damage Identification

In recent years, structural damage identification becomes an important component of structural health monitoring so that it attaches more and more attention and research by scholars. Among them, structural damage identification of bridge for safety of bridge structure’s service is of great significance. So far, many academics of bridge structure damage identification has done quite a bit of research, and made a lot of identifying indicators and theories. But most of the research is using finite element model by means of theoretical analysis and research, thus no validated in the actual bridge. Study on damage detection of cable-stayed bridge and even more so, and use of building scale model of cable-stayed bridge for study on damage detection of cable-stayed bridges less.This article first of all on the background of Jintang bridge, based on the geometric similarity theory similar to the derivation of a static model of the bridge, based on the use of similarity theory of dimensional analysis the inferred similarity relation model of the bridge. Similarity relation of the dynamic model is ideal, and in the actual production of the model to simplify it, in order to make a scale model of Jintang bridge for testing. In order to verify the correctness of the model, experimental data and its finite element models were compared.Secondly, after the establishment of Jintang bridge model, based on flexibility curvature, poor flexibility curvature, coefficient of flexibility curvature mutation of indicators to identify the damage of the main girder of cable-stayed bridge. Through recognition of these three indicators compared with the sensitivity of verification are presented in this article are based on flexibility curvature mutation coefficient sensitivity of the indicators than the other two indicators, showing the validity and applicability of the indicators.Finally, in this paper, the structure of the modal frequency and modal shape of the order’s influence on the coefficient of flexibility curvature mutation has carried on the preliminary discussion, the results show that based on damage identification of modal flexibility curvature mutation factor targets with increasing modal order of their numerical level off.