Kullanımda olan bir çelik demiryolu köprüsünün operasyonel modal analizi ve sonlu elemanlar modelinin güncellenmesi

In our country Turkey visual inspection techniques are used for health and safety checks of bridges. Outcomes of such methods are highly dependent on the experience and the personal skills of the technician, and are most of the times unable to detect hidden structural damages. Detected damages by these methods are usually too severe and progressed that most of the times; it is too late to take any precaution. From this point of view, the vibration based SHM with the potential of detecting small invisible damage must be included in the standard visual inspection techniques. The main aim of this thesis is to apply finite element model updating based structural health monitoring method to 199+325 steel railroad bridge on the route of Basmane-Dumlupinar which is under service for more than a century. Application of this technique will eliminate the deficiencies/shortcomings in visual inspection techniques. With this project, it is targeted to make this technique a part of standard inspection techniques used by Turkish Republic State Railroads Department. Ambient vibration data were obtained from the bridge by means of accelerometers and the modal parameters were determined using operational modal analysis methods. The modal parameters of the bridge were estimated using dynamic data collected over the bridge. These estimated modal parameters are useful to detect the existence, location and amount of damage. In addition, a calibrated finite element model of the bridge and a database of its modal parameters can be used for comparison purposes in case of any damaging natural event occurring in the future.