Intelligent Sensing for Innovative Bridges

Abstract

This paper discusses two types of fiber optic sensors used for monitoring highway bridges in Manitoba, Canada. The first, the Taylor Bridge, is the longest smart bridge built in North America and was completed in 1997. Four girders, large portions of the deck slab and the barrier wall are reinforced with carbon and glass fiber reinforced polymer (FRP) materials. The bridge is remotely monitored using fiber optic sensors embedded in the girders, the deck slab and the barrier wall to provide continuous information on the health and structural performance of the bridge. Signals obtained from the optical sensors are transmitted through a telephone line, thereby allowing an office-based engineer to monitor the stresses and strains via a computer anywhere in the world. The paper discusses the expert system program used to reduce the data collected from the bridge into engineering information which can be used to assess the performance of the FRP material and the behavior of the bridge. The second, the Norwood Bridge, is another innovative bridge also built in Winnipeg, Manitoba. The bridge is a complex precast reinforced concrete structure including an innovative mechanical connection at the supports to provide continuity. Monitoring of the bridge was requested by the owner, the City of Winnipeg, to verify structural behavior during different stages of construction and operation. A different type of fiber optic system was used in this bridge. Both the Taylor and the Norwood Bridge projects were undertaken by the Network of Centres of Excellence on Intelligent Sensing for Innovative Structures (ISIS Canada) which was able to provide the valuable link between the emerging new technology in structural remote monitoring and the construction industry.