Reliability of low-cost wireless sensors for civil infrastructure

摘要

The long-term reliability of a prototype, threshold corrosion sensor is demonstrated using data collected during an eighteen-month accelerated corrosion test. The sensors were embedded in reinforced concrete slabs, subjected to alternating wet/dry cycles, and interrogated periodically during the test. The frequency signature of the sensor changes after the steel sensing wire corrodes, providing a convenient and noninvasive technique for determining when a threshold amount of corrosion has occurred. The results indicate that the sensor data are reliable, but that some variability of readings should be expected due to the close tie between the presence of cracks in the concrete and the chloride levels, as the locations of the cracks are not known at the time that the sensors are embedded in the concrete.