Damage Detection of RC Columns in Shaking Table Tests by Singularity Analysis of Their Acceleration Responses

Quick state judgement of important infrastructures such as bridges is required especially after the earthquake. The application of accelerometers which are already installed on many infrastructures can realize this judgement, but the method to detect the damage of structures from only the acceleration information has not been established yet. In this study, by applying singularity analysis based on wavelet transform to the acceleration data, we tried to detect the damage 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 occurred when RC columns had damages such as cracks and rebar yielding.