Damage Imaging in Mesoscale Concrete Modeling Based on the Ultrasonic Time-Reversal Technique

Abstract

A novel method combining the time-reversal method (TRM) with wavelet analysis was proposed for damage imaging in mesoscale concrete modeling. The damage was imaged by the convergence of time-reversed wave signals after wavelet analysis. Through numerical study, three concrete models of different damage sizes were built with randomly distributed aggregate particles. The time-reversal process was simulated using the reverse damage-scattered ultrasonic wave signals as excitations recorded by the sensors. Then, the wavelet analysis was employed to extract certain frequency component, which can enhance detection precision and the signal-to-noise ratio. The damage imaging showed clearly the location of the defect. The results from experimental testing also demonstrated that this detection technique is an efficient and effective method for damage imaging in mesoscale concrete.