Low Cost Structural Health Monitoring of Bridges Using Wireless Senspot Sensors.

摘要

Deterioration of highway bridges is a common, yet complex problem. To protect highway bridges, this project combines a number of recent and emerging technologies microstructured sensing, ultra-lowpower wireless communication, and advanced microelectronics into a novel, small, and lightweight wireless device known as SenSpot. SenSpot sensors are based on Active RF Technology (ART), which offers a high performance method for large-scale sensing, wireless synchronization, and ultra low power wireless communication. To evaluate ART technology, the project investigators studied laboratory and field performance of SenSpot sensors. In particular, research was conducted to study performance of SenSpot sensors in accurate measurement of strain and tilt (inclination). Laboratory experiments showed that although SenSpot sensors operate under extremely tight energy constrains and consume less that 4 microwatts of power, the devices provide a very accurate measurement of strain and tilt. Moreover, field performance of SenSpot sensors installed on a bridge on I-495 was closely analyzed. They study showed that SenSpot sensors used to measure tilt on the bridge bearings provide a consistent readout with the expected change in the orientation of the bearings as a result of thermal expansion/contraction of the bridge deck; hence, SenSpot sensors provide a reliable remote monitoring tool to detect instances where bridge bearings could possibly freeze or overturn.