Long gauge length fibre optic sensors have been installed on bridges and pipelines to monitor their long-term structural integrity. These sensors measure the average displacement or strain over their gauge length due to mechanical or thermal loading. It is shown that long gauge length sensors can provide an estimate of the maximum bending strain for beam-type structures, such as bridge girders or pipelines, subject to sag. Bending and hoop strain test results are presented for bridges with composite reinforcements bonded to concrete girders and columns that were statically loaded at various locations to assess the integrity of the bond interface. These sensors can also provide information on corrosion-induced wall thinning of pipelines based on changes in the local strain field due to internal pressure in the line. Test data are presented for measuring pipeline corrosion using different fibre optic sensor configurations.Key words: fibre optic sensors, bridges, pipelines, integrity monitoring.

This paper describes the architecture of a comprehensive seismic monitoring system developed in 2009 by the British Columbia Ministry of Transportation and Infrastructure (MoT) and the University of British Columbia, Canada. The main purpose of the British Columbia Smart Infrastructure Monitoring System project is to instrument and monitor key structures to provide confirmation of their seismic capacity, assist in focusing retrofit efforts, detect structural damage, and provide rapid damage assessment of those structures, following a seismic event. The automatic creation of shakemaps following an earthquake provides information for the MoT's non-instrumented bridges. The public notification systems and web pages have been developed to display real-time seismic data both from the strong motion network and seismic structural health monitoring network. Tools and methods have been developed to help transform the current practice of inspecting and evaluating structures to a more rational and effective one that uses the up-to-date sensing technology with fast and efficient techniques.

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Canada's chief vulnerability to earthquakes is concentrated in a few urban regions. The south-west coast of the province of British Columbia is subject to the hazard posed by the Cascadia subduction zone with the associated earthquake scenarios of shallow crustal events, deeper subcrustal events and magnitude 9 megathrust earthquakes. The Geological Survey of Canada operates a new real-time ground motion reporting network of accelerographs in British Columbia. As of January 2006, one hundred instruments have been deployed, most concentrated in and around the urban centres of Vancouver and Victoria. The instruments combine several functions, serving as continuously recording strong motion accelerographs, and, at the same time, as sensors which automatically detect events and report real-time ground motion parameters such as peak ground acceleration (PGA), velocity (PGV), and spectral intensity (SI). Instruments form a network using various physical means of communications, including wired, wireless and satellite Internet links. Standard Internet protocols are employed to convey ground motion reports. The network thus does not depend on the existence of a seismic data centre to analyze full waveform data, generate an alarm and subsequently disseminate ground motion maps. Instead, ground motion parameters from an instrument are relayed directly to disaster response agencies and lifeline and critical infrastructure operators. A prototype client system, which depicts peak ground motion values on a thematic map, is in operation with the Ministry of Transportation in British Columbia. The reliability of alarms from this network as well as the quality of the generated shake maps depend primarily on station density. Since the instruments are inexpensive to own, deploy, and operate, dense arrays have become a realistic proposition.

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