Monitoring of vehicle using cement-based piezoelectric sensors

Monitoring on vehicle is significant to management and maintenance of highway. A method based on cement-based piezoelectric sensors to monitor vehicle is developed and its feasibility and validity are verified by field test. First, fabrication and performance of the sensor was presented. And then, two piezoelectric sensors were embedded into a concrete beam as the sensing element installed under road. In the field test, four beams were installed in one lane for counting traffic flow according to the number of peak groups in the responses of sensors, recording the speed of vehicles in terms of the time shift between the responses of two sensors in two rows and the distance of two rows, and measuring the gross weight of vehicles using the amplitude of peaks in sensor's response and its calibrated sensitivity. Finally, the results of field test show that the cement-based piezoelectric sensor can correctly measure the volume, speed and weight-in-motion of vehicles. So, the method using cement-based piezoelectric sensors to monitor vehicle is feasible and valid.