Identification of damages in the vertical links of a CFST arch bridge model

摘要

The researchers have designed and built a CFST arch bridge model in their laboratory.In this paper,static and dynamic analyses of the model’s vertical links in both undamaged and damaged cases were studied using ANSYS.In the damaged cases,the axial forces in the vertical links that neighbor the damaged link showed a marked difference.However,the axial forces of the links far from the damage location showed little change.In addition,all the natural frequencies of the bridge changed after introducing the damage.The largest change occurred in the frequency corresponding to the third vertical bending mode.Likewise,the modal curvature of the longitudinal girders is also sensitive to damage in the vertical links-especially the curvature of the second vertical bending mode.By analyzing the changes in the modal curvature,the location of the damaged vertical links can be determined.A method for identifying the locations of damaged vertical links is proposed by using a combination of the changes in the natural frequencies of the structure,the modal curvatures of the longitudinal girders,and the axial forces of the vertical links.