Neda Baghiee - PhD Structural, Ferdowsi University of Mashhad
Mohamad Reza Esfahani - Professor, Civil Engineering Department, Ferdowsi University of Mashhad
Kazem Moslem - Assistant Professor, Civil Engineering Department, Ferdowsi University of Mashhad

This paper presents a method to identify damage in bridge structures based on the flexibility matrices in the modal strain space. In the study by the Ritz vectors extracted from flexibility matrix, the damage is identified. The localization approach is applied to low levels of damage on the prestressed concrete girder of simply supported bridge, with a focus on using a small number of sensors and only the fundamental mode of vibration. The validity of the method is also demonstrated using experimental modal data of a plate girder from I-40 Bridge over the Rio Grande. The predictions were found to closely match the actual response of the bridges. The proposed method can detect the damage in bridge structures using a limited number of sensors and vibration modes

Bridge, Damage, Flexibility, Modal strain, Ritz Vectors