Hashem Jahangir - Assistant Professor, Department of Civil Engineering, University of Birjand, Birjand, Iran,
Hamed Hasani - M.Sc in Structural Engineering, Department of Civil Engineering, University of Birjand, Birjand,Iran,
Fatemeh Shahbazi Aval - B.Sc student of Civil Engineering, Department of Civil Engineering, University of Birjand, Birjand,Iran,

In order to increase structural operation life and prevent sudden collapses, detection and localization of damages is required. Damage detection can be obtained by processing structural signals without undamaged data as a baseline. In this paper, wavelet transformation, which is one of the newly developed signal processing methods, is used to identify damage in reinforced concrete beams. The sensitivity of numerical and experimental modal strains has been studied as wavelet signals, and a damage index is introduced. For achieving Experimental data, modal tests are conducted on reinforced concrete beams bearing different static loading steps. Concentrated and distributed damages in some parts of numerical samples are caused by concrete elasticity modulus reduction. Numerical and experimental results show that damages in specimens can be identified by wavelet transform of modal strain based on statistical approaches, and structural rehabilitation will be possible by putting this method into practice.

Concentrated Damages, Distributed Damages, Wavelet Transform, RC beams.