ABSTRACT
Early judgment of damage level of infrastructures is required after the earthquake. In order to achieve this, the application of accelerometers which are already installed on many infrastructures is expected, however the method to detect the state-change of structures from only the acceleration information has not been established yet. In this study, by applying wavelet transform to the acceleration data, we tried to detect the statechange of structures. As a result of applying wavelet transform to the acceleration data measured on RC columns which had damage by shaking table test, we could detect singular points of the acceleration waveform which occurs at points where the signal itself or its derivative changes discontinuously. By comparing the singular points with the strain data of rebar and video records, it was shown that most of the singularities in acceleration occurred when RC columns had damages such as cracks and rebar yielding.
