Properties and mechanisms of the self-sensing piezoelectric concrete sensor for structural health monitoring

The use of self-sensing concrete sensors to estimate the amount of force applied or to estimate damage levels to structures as a new approach has been considered in structural health monitoring studies. In this study, the possibility of using piezoelectric concrete sensors as load or stress sensors to the concrete column has been investigated. The importance of this research in the development of smart infrastructure is based on the response of concrete sensors to conventional sensors. For this purpose, different piezoelectric concrete sensors were made with different percentages of carbon nanotubes and were subjected to dynamic loading and the appropriate sensor with appropriate sensitivity and less turbulence was obtained by adding at least 0.15% carbon nanotubes by weight of cement. In order to simulate the performance of the concrete column under external load until the failure and analysis of its behavior, based on the response of the concrete sensor, a small cubic concrete sensor with dimensions of 5 cm was made and placed in a concrete column. By loading the concrete column until the failure, the output of the sensor was monitored and the behavior of the concrete column was analyzed based on the concrete sensor response. The results showed that the concrete sensor could accurately estimate the final force that can be applied to the column up to failure. The sensor demonstrated that it could differentiate the different phases of the concrete column under the loading up to failure.