Use of sensors in monitoring civil structures

Abstract

This thesis surveys the use of sensors and sensor networks in monitoring civil structures, with particular emphasis on the monitoring of bridges and highways using fiber optic sensors. Following a brief review of the most widespread form of civil infrastructure inspection -- visual inspection -- the thesis describes the anatomy, mechanisms, and types of fiber optic sensors and characterizes the tradeoffs involved in choosing between fiber-optic and conventional sensor technologies. The thesis then presents a survey of contributions to this field, followed by a discussion of deployed applications of fiber-optic sensors, many of them in North America. The latter portion of the thesis first briefly discusses the emerging technology of wireless sensor networks and then presents an abbreviated case study comparing the costs and time required to deploy a fiber optic system to traditional visual inspection on the same structure. The case study suggests that the fiber optic sensors are a cost-effective technology, particularly when indirect savings are considered. The thesis concludes with some comments on the prospects and challenges for sensor technologies in civil infrastructure monitoring.