Canadian solutions to the global infrastructure crisis

Bridges, roads, parking garages, buildings, dams, piers, and telephone poles — thanks to new Canadian technology these structures can now 'see' their own wear and tear, allowing researchers to predict and prevent costly repairs or disasters.

Researchers with the Intelligent Sensing for Innovative Structures Network (ISIS Canada), funded primarily through the federal Networks of Centres of Excellence program, are using a stronger, longer-lasting material to build infrastructure and they are adding tiny fibre optic lines of sensors and lasers to the material so they can monitor the stresses and strains on a structure 24 hours a day.

The material is a kind of fibre reinforced plastic which is commonly used for building airplane and car bodies. It is non-corrosive, 20 per cent lighter and 10 times stronger than the steel currently used to support concrete structures. It is produced without polluting the environment and it is reusable and recyclable.

Hair-like optical fibre sensors are integrated like a system of nerves into the fibre reinforced plastic so they run throughout the structure. They are resistant to corrosion and fatigue, immune to electromagnetic interference and able to extend over large distances without being affected by either electrical storms or man-made electrical sources.

The sensors relay detailed information about the structure's safety and longevity to remote computerized monitoring sites via telephone and satellite links. So from thousands of kilometres away, the central location can monitor the condition of hundreds of structures, eliminating the need for costly site visits.

"We ask a bridge questions and it answers us," explains Sandra Martel, engineer and technology implementation officer for ISIS Canada.

The ISIS Network of Centres of Excellence is jointly funded by the Natural Sciences and Engineering Research Council, the Medical Research Council, and the Social Sciences and Humanities Research Council. The NCE funds going to ISIS result in an average annual investment in research and development of close to $2.4 million.

ISIS's 'smart' technology can be used for patching and wrapping existing concrete structures to give old structures superior performance and durability, as they did recently in Sherbrooke, Quebec. ISIS researchers rehabilitated and reinforced the Webster Parkade, a 37-year-old multi-storey parking garage in downtown Sherbrooke. The project won an award from the Quebec Ministry of Municipal Affairs.

"The parkade was abandoned and it would have had to be demolished to make way for a new one," says Dr. Sami Rizkalla, ISIS president and professor of civil engineering at the University of Manitoba. "But using ISIS technology, we were able to renovate it instead, saving thousands of dollars in new construction costs."

ISIS technology can also be used for building completely new structures and it is easily integrated into existing construction methods and techniques.

In July 1997, construction of the Headingly bridge was completed. The 500-foot bridge, located over the Assiniboine River in Headingly, Manitoba, was built with one-half ISIS technology and one-half standard building materials. This way, researchers can see what the long-term benefits of 'smart' technology may be over conventional construction. The ISIS side of the bridge is not expected to need repairs for 25 years; most bridges must be repaired every 10 to 15.

And with the global infrastructure building boom of the post-second world war era giving way, these repairs are perhaps more necessary than ever. Over 40 per cent of the bridges operating in Canada were built over 30 years ago, and most are in urgent need of replacement or rehabilitation.

What's more, many bridges and other structures are deteriorating due to corrosion from Canada's harsh climate and extensive use of de-icing salts. They are also under the demands of continuously increasing traffic loads.

Experts say Canada faces an "infrastructure deficit" — the gap between needed and actual infrastructure investment — of approximately $74 billion. Cost estimates to remedy all deficient bridges alone exceed $10 billion. And with limited funds available for improvements, private and public sector organizations must strive to do more with less.

The good news is that it costs 30 to 40 per cent less to repair a bridge using ISIS technology. And while the costs for building an entirely new structure are still slightly more expensive than conventional construction, Dr. Rizkalla expects the price to level out once ISIS materials can be produced commercially. And there are already two companies planning to do so.

And while the initial cost of building a new structure with ISIS technology is slightly higher for now, Dr. Rizkalla says the long-term savings more than make up for it. He says ISIS technology can triple life cycles of new structures and virtually eliminate costly maintenance, saving millions of dollars in the long run.

Not only will these savings benefit Canadian taxpayers by reducing infrastructure spending, but ISIS technology also has great potential to tap into the $900 billion international market demand. The infrastructure crisis is global in its scope and ISIS is receiving requests for information from such interested countries as Japan, Scotland, Lebanon, and the U.S.

Their work is of particular interest to countries ravaged by earthquakes. The ISIS materials make structures stronger and more resistant to damage, and the fibre optic sensors monitor the strains and shifts in the structure. And Dr. Rizkalla says these sensors may even be able to give warning signs that could help researchers predict earthquakes.

ISIS researchers are now organizing missions so they can study foreign environments and see how they can adapt their work. They are also currently working on applying their 'smart' technology to a host of other structures like hydro towers and highway signs. One hundred and twenty researchers from 12 Canadian universities are involved in research for ISIS and there are currently 18 field-testing projects under way in seven provinces.

The practical and financial benefits of ISIS technology are many. It can save millions in infrastructure costs and make structures safer and longer-lasting. It also holds the promise of generating thousands of jobs, opening the door to future national and international research and development, and boosting Canadian industry and economy.

For more information please visit the ISIS Web site.