水泥基压电传感器在交通量监测中的应用:(2)现场试验(英文)

介绍了一套基于耐久性好、价格低廉及全天候运行的水泥基压电传感器的交通量监测系统。首先将两个水泥基压电传感器埋入一段混凝土梁的两端,以此梁作为埋入路面下的传感单元。再将4根测试好的混凝土梁埋入一条车道的两道沟槽内,每道槽内放入两根。系统运行时通过传感器数据分析来计算交通流量,即以测试信号中的峰值个数计算车辆数,以传感器的响应之和计算车重,并以两道沟内传感器响应的时间差及距离计算车速。其后通过已知重量的卡车进行传感系统现场标定。目前,该套系统已经成功安装到一座高速公路桥梁中,且运行顺利。通过与视频监测结果的对比表明,该系统能够准确的获得车流量、车辆速度以及近似重量。进而可见,该水泥基压电传感器在交通量监测中是有效的。

Cement-based Piezoelectric Sensor for Monitoring of Highway Traffic II: Field Test

In this paper, the field test of a traffic monitoring system based on a novel cement-based piezoelectric traffic sensor which is durable, inexpensive and can work under any weather conditions are presented. A concrete beam with two piezoelectric sensors respectively embedded at its two ends, as a sensing element, is designed to be installed under the wearing course of highway. Four beams, two pieces in two rows, are installed in one lane, for counting traffic flow according to the number of peaks 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 calibrated sensitivity of the sensor. After installation of the beams, the field recalibration using a known-weight truck is carried out for checking the validity of the sensors. Online running of the developed traffic monitoring system installed on the exit road of a highway bridge in HK was performed. The results of field test show that the traffic monitoring system can correctly measure the volume, speed and gross weight of vehicles, which indicates that the system has a good potential to be used in management and health monitoring of highway bridge.