Feasibility evaluation of the development of type 1-3 acoustic emission sensors for health monitoring of large bridge structures

As sensors and reinforced concrete materials are coupled and mismatched when the acoustic emission (AE) technology is used to monitor large civil engineering structures, the type 1-3 cement-based piezoelectric composites as the most efficient method are used to address the problem. Specifically, a cut-filling method with PZT as the functional phase and cement/epoxy-based composite as the matrix was adopted. The matrix limited the radial vibration mode between each PZT column, resulting in type 1-3 cement/epoxy-based piezoelectric composite with pure mode. The interaction between regular and irregular ceramic columns has been proven to cause thickness modal peaks at 80 kHz, 220 kHz and 850 kHz. A type 1-3 cement-based AE sensor with a wide frequency range was fabricated by using a type 1-3 cement/epoxy-based piezoelectric composite material as the piezoelectric element and cooperating with a matching layer, backing layer, shielding layer and encapsulation layer. The acoustic emission sensor is used to monitor the concrete fracturing process, and the relationship between the concrete damage and the acoustic emission characteristic values collected by the sensor is clarified. The sensor has been installed on the Yellow River Bridge for online monitoring via Alibaba Cloud.