Health Monitoring of Rubber Bearing by using Acoustic Emission Test

摘要

Many laminated rubber bearings of bridges have been in service more than 10 years in Japan. As they have suffered traffic loads and earthquake vibrations over the long term, deterioration such as fatigue, ozone cracks and aging has become serious issue. This study performed health monitoring of rubber bearings by using acoustic emission (AE) method which is one of non-destructive tests. Verification of the method was conducted by laboratory tests as well as field measurements. The AE activities and their parameters of the deteriorated bearings were compared with new ones. The results showed that the internal damage of the rubber bearings could be estimated through the activities of the AE parameters. Many AE hits and large AE parameters were observed from the deteriorated rubber bearings through the laboratory tests and the field measurements, however, few AE activities were observed from the new bearings.