A cement-based piezoelectric sensor for civil engineering structure

A new aggregate-like sensor using piezoelectric ceramic as sensing element was designed, fabricated and tested. The sensor was made by bonding together two cuboids of hardened cement paste with a commercially available piezoelectric ceramic plate in between, which is the sensing element. A new adhesive was developed during the fabrication of the sensor. The sensor was tested on its basic performance with a charge amplifier measuring system. First, the frequency response of the sensor was investigated in the general frequency range of civil engineering structure, which is from 0.01 Hz to 40 Hz. Then the relationship between output and input of the sensor was tested. Finally, complex, random and square loads were applied to observe the performance of the sensors. The excellent compatibility with concrete and the good sensing performance enable the aggregate-like sensor to be easily embedded into concrete structures like a real aggregate and to reliably monitor the vibration of host structure. There is a good potential for such a sensor to be used in structural health monitoring.