Monitoring damage of arch bridge suspender using acoustic emission technique

Conventional non-destructive methods can't be dynamically monitored the suspenders' damage levels and types, so acoustic emission (AE) technique is proposed to monitor its activity. The validity signals are determined by the relationship with AE rise time and duration time. The ambient noise is eliminated using float threshold value and placing a guard sensor. The cement mortar and steel strand damage level is analyzed by AE parameter method and damage types are judged by waveform analyzing technique. Based on these methods, all the suspenders of Sichuan Ebian Dadu river arch bridge have been monitored using AE techniques. The monitoring results show that AE signal amplitude, energy and counts can visually display the suspenders' damage levels, the difference of waveform and frequency range express different damage type. The testing results are well coincide with the practical situation.