Field Demonstration Projects
Quebec
Centennial Park School & Gabrielle Roy School
 Glass fibre reinforced polymer (FRP) sheets were used to strengthen 1,800 beams in two similar schools in Chateauguay, Québec that were damaged as a result of the 1998 ice storm. Following the storm, previously existing shear cracks in the roof beams widened and, in a few cases, partial failure occurred. The consultant, Soprin ADS, chose to reinforce the webs of the prestressed prefabricated roof panels with glass FRP sheets supplied by Composite Retrofit International Inc. and applied by Construction Interlag.
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Champlain Bridge
 In October 1996, Jacques Cartier and Champlain Bridges Inc. selected glass FRP to repair one pier of the Champlain Bridge located in Montréal. The base of the bridge pier is submerged and subjected to a strong current and because it is located at the confluence of two parts of the St. Lawrence River, it is particularly vulnerable to ice collisions during the winter and early spring. Nine layers of glass fibre composite sheets were installed for an overall thickness of 10-mm on a four metre height. A special reel was used to facilitate applying the nine layer glass FRP envelope for an overall thickness of 10-mm on a 4-m height. The reel simplified handling the lengths of fabric saturated with resin before arriving at the pier.
Installation time was reduced significantly over conventional rehabilitation methods and the multiple wraps of glass FRP meant less material overall was required. The FRP wraps provide strengthening as well as added protection against damage from both ice collisions and corrosion. So far, the rehabilitation has been subjected to some of Québec’s worst winters on record and has shown excellent performance.
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Eustis Bridge
 Québec has over 80 covered timber bridges displaying a wide range of structural integrity. In rehabilitating these bridges, the general appearance and structural concept have to be preserved. This usually means conventional solutions must be bypassed for techniques still considered innovative. In addition, restoration often involves expensive replacement of structural members, one at a time. ISIS Canada offers an alternative solution that has already been applied to the Eustis Bridge in Compton Station, Québec.
This 30-m long, turn of the century covered bridge near Sherbrooke is the first timber bridge in Québec to be reinforced using composite materials. It is still early in this new area of applied research, and already the material is proving to be a viable solution. It is certainly lightweight and unintrusive, and in this case, aesthetics have been preserved and the structure returned to its former youthful glory. In fact, the Eustis Bridge is stronger than ever.
The objective of this ISIS Canada research project was to demonstrate applicability and durability of the carbon fibre rehabilitation technique. It was carried out in collaboration with the Municipality of Compton Station, the Ministry of Transportation of Québec, and the Ministry of Culture and Communications in Québec. Sika Canada Inc. donated the CarbDur carbon-fibre composite plates.
In order to evaluate the benefits of reinforcing old timber bridge members without actually replacing them, some of the disassembled parts were recovered and taken to the Université de Sherbrooke's structures laboratory. It is difficult to carry out conclusive tests on timber because the material itself is so variable. To eliminate some of the unknowns, the recovered members were literally sawed in half lengthwise, one half to be reinforced, the other not. By subjecting the two halves to the same loading test, the increased strength and stiffness properties can be observed and measured.
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Frontenac Power Plant
 The Frontenac Power Plant was built in 1910 and includes a water chamber that is part riveted steel and part concrete with a diameter of 3.66-m. In 1917 the water chamber underwent major repairs and in 1987 light sandblasting was applied to remove rust from the walls. The steel inner wall was reduced from 9.52-mm to a residual thickness of 6.35-mm. Moreover, the concrete section of the chamber was in an advanced state of erosion. At this point, the Hydro-Sherbrooke authorities decided to rehabilitate the chamber, using a process that would not only protect what remained of the walls, but also restore the chamber to its original capacity.
Applying fibre reinforced polymers (FRPs) to both the steel and concrete sections was the best solution. In addition to reinforcing the water chamber, the repair would also contribute to a burgeoning knowledge base of FRP applications in high-humidity environments.
A total of 275 square metres of FRP material was installed. For the steel section, two layers of FRP were applied to the surface - one each to the exterior and interior. This structure was built using riveted plates, the rivet heads of which were in various states of decay. Special precautions were necessary to ensure continuity in the long-term behaviour of the FRP.
Two layers of FRP were applied to the interior of the concrete section where incessant water leakage presented a real challenge to completing the rehabilitation. Water was seeping through the door during the installation and so to prevent the resin from eroding, the water was canalized. In addition, it appeared water was seeping through the highly porous concrete. By doubling the amount of resin applied, the porous concrete surface was saturated (having accounted for absorption) and an impenetrable bond was achieved.
Tests were carried out in the Université de Sherbrooke laboratories at the outset of this project in order to verify the bond of the composite to a steel surface. For this purpose, eight 12.7-mm thick by 100-mm diameter plates were manufactured and a 25.4-mm nut was welded to one side of each plate, while sandblasting was applied to the other side. Four specimens were manufactured: two with clear resin, and two using a denser resin.
The repairs began on August 25, 1998 and were completed less than one month later on September 23. Sandblasting was initially used to eliminate all rust deposits on the steel surface and all other particles on either the steel or concrete. Different resin mixes were used to accommodate the repair site conditions.
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 Gentilly I Nuclear Reactor Containment Structure
Gentilly-1, the first nuclear plant at Gentilly, Quebec, became operational in May 1972 and was operated intermittently until 1978, after which it was partially decommissioned. International (IAEA) and Canadian (AECB) guidelines are being followed to provide monitoring and surveillance programs which ensure conditions at the site continue to meet safety requirements. While it was originally to be maintained for 40 years after decommissioning, plans now are to extend this maintenance period to 100 years.
AECL and ISIS carried out a testing program to determine the strength and durability characteristics of the concrete containment structure. Innovative FRP technology has been used to enhance the strength of the structure and to improve the durability and appearance of the building.
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 Hydro Underground Chambers
In Québec, more than 50,000 similar chambers have been installed over the last 30 years to house special devices used for Hydro-Québec electrical transmission lines. On an annual basis, two percent (approximately 1,000) of these underground steel-reinforced concrete chambers are so corroded they must be replaced. In 1999, two chambers were constructed at the Université de Sherbrooke as a preliminary feasibility study for the application of fibre reinforced polymer (FRP) reinforcements.
Ten more are being produced and outfitted with sensors for monitoring. The newly-built reaction wall at the Université de Sherbrooke will be used to test two of the chambers to failure. The remainder will be located throughout Québec.
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 Joffre Bridge
In August of 1997, the Province of Québec accepted the challenge of constructing an innovative bridge using carbon fibre reinforced polymer (CFRP). By opening day December 6, 1997, the Joffre Bridge, spanning the Saint Francois River, was another significant contribution to the ever increasing collection of polymer reinforced bridges in Canada. A portion of the Joffre Bridge concrete deck slab is reinforced with carbon FRP, as is a portion of the traffic barrier and the sidewalk.
The bridge is outfitted extensively with different kinds of monitoring instruments including fibre optic sensors embedded in the FRP reinforcement (smart reinforcements). Over 180 instruments (fibre optic sensors, vibrating wire strain sensors and electrical strain gauges) are installed at critical locations in the concrete deck slab and on the steel girders, to monitor the behaviour of the FRP reinforcement under real-time conditions. The instrumentation is also providing valuable information on long-term performance of the concrete deck slab reinforced with these new materials, in that all the sensors transmit data to a telephone line for remote monitoring of the structure’s behaviour.
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 Laurier-Taché Parking Garage
Public Works and Government Services Canada (PWGSC) is currently undertaking the reconstruction of the interior structural slabs of the Laurier-Taché parking garage in Ottawa/Hull. FRP-composite bar technology is incorporated into the project and will be monitored over an extended period of time. This project allows direct field assessment and long-term monitoring of FRP composite bars in a structure subjected to harsh environmental and loading conditions.
After finalizing the design for the type and amount of FRP reinforcement, full-scale slab prototypes, with identical reinforcement configuration to that of the final design, will be constructed and tested. The structural slabs will be instrumented for internal temperature and strain data collection. Embedded gauges will be used to monitor slab behaviour from the time of initial concrete placement to several years after construction.
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 Saint Étienne-de-Bolton
This landmark restoration project was completed in a mere three weeks. Twelve out of eighteen circular columns were experiencing severe deterioration because the steel rebars were in an advanced state of corrosion. Nine of the damaged columns were repaired using fibre reinforced polymers (five with carbon FRP and four with glass FRP) while the remaining three were repaired using conventional materials and methods. For each column, one layer was first installed with the fibres aligned vertically. A second layer was applied with fibres placed circumferentially.
In a successful effort to validate this method of repair, fibre optic sensors were installed on four of the columns to measure reactions to extreme temperature variations, corrosion and loading. This project proved that the significant savings in labour outweigh the increased expense of FRPs. Because the materials are so light-weight and the installation method so easy to learn and apply, construction time and the size of the work crew are reduced over conventional methods. In addition, no form-work is required and traffic flows as usual.
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Sainte Émélie-de-l'Énergie
 In 1997, ISIS-Sherbrooke obtained a research contract with the Ministry of Transportation of Québec to identify a potential bridge-strengthening scheme with composite materials, and to conduct an analytical study of such a repair. The selected structure was a single-span, simply supported bridge with T-section, which is characteristic of many bridges currently in use in Québec.
It would thus be eventually possible to apply the same strengthening method to other bridges presenting similar structural deficiencies. Test beams were fabricated to evaluate various reinforcing schemes in bending and in shear, and were used to check the validity of the analytical procedures developed for this project. The four T-beams were reinforced in order to demonstrate the potential increase in strength as was requested for the reference bridge proposed by the MTQ. Special attention was paid to the scale effect in order to demonstrate acceptable correlation between the laboratory results and the actual structure being considered.
Durability of the composite material reinforcement was also included in the study. Specimens were tested to evaluate the influence of freeze-thaw or wet-dry cycles on both the composite materials and the concrete-composite interface. Preliminary results obtained in this project confirm that the two kinds of cycles have a negligible effect on the composites themselves and on their bond to the support surface. Long-term durability tests continue.
The experimental study was followed, in the fall of 1998, by the strengthening of the actual reference bridge. Preparation of the site, including curing of some concrete used in the repair, took three weeks. Installation of the composites took five days over a two-week period.
Sensing devices were installed on the bridge in order to monitor its behaviour. The 66 instruments on the bridge include 28 strain gauges, 10 thermocouples, 20 optic fibres with Bragg sensors and 8 with Fabry-Perot sensors. Positions of the sensors were selected in such a way that complementary readings can be obtained from the various types of instruments, and to validate the data obtained from the experimental optic fibre sensors. The repair work was done under close supervision of the Ministry of Transportation, which conducted the loading tests before and after the repair work. Additional loading tests will be conducted in the future in order to evaluate the behaviour of the repaired structure, and to validate the optic fibre technology for this type of application.
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Université de Sherbrooke Business Faculty
 In November 1995, repair work was carried out on a building at the Université de Sherbrooke. Glass fibre composite sheets were used to strengthen and protect two reinforced concrete columns located at the entrance of the Business Faculty. The columns’ steel rebars had corroded significantly and this was identified as the main cause of the concrete’s cracking and spalling. The extent of the damage was particularly evident once the damaged concrete was removed. The repair work was carried out under cold and snowy conditions, so a makeshift canvas shelter was set up for protection from the elements. Otherwise, the column wrapping was executed in a normal fashion. After nearly two years the appearance of the repaired columns is essentially identical.
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Université de Sherbrooke Pedestrian Bridge
 A student design competition for a pedestrian bridge enabled the use of new-generation structural technologies. Set up by ISIS, the aim of this competition was to design a pedestrian bridge with a six-metre covering with access to a new entrance to the Faculty of Engineering at the Université de Sherbrooke. The objective of this project was to provide the opportunity for ISIS Canada students to participate in the design of a construction project incorporating composite materials with the integration of new fibre optic monitoring technologies.
The composite materials for the structures and the monitoring of fibre optics are two main research goals of ISIS Canada. The winning team from Queen's University was invited to participate in the final design of the project with the engineering firm responsible for the project.
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Webster Parkade
 Since 1996, the Canada-Québec Infrastructure Program has ensured that a variety of civil engineering projects incorporate new technologies. It is through this program that the City of Sherbrooke undertook the revitalization of the 37-year-old Webster Parkade in the fall of 1996. Fibre reinforced polymers (FRPs) were used to rehabilitate the 1959 Webster Parkade. Glass and carbon FRPs were used to rehabilitate and reinforce columns, which had lost their initial capacity over the years due to corroding steel rebars, and to protect column bases exposed to de-icing salts during the winter.
FRPs were used to strengthen beams that didn’t conform to current standards concerning their bending and/or shear capacity. An integrated structural sensing system was installed to monitor the behaviour of the parkade under loading variations. Infrared rays were used to determine the success of the bonding between the FRPs and the concrete surfaces.
The success of this rehabilitation was acknowledged with the Innovation Award from the Québec Ministry of Municipal Affairs. This award recognizes ISIS Canada’s contribution to the preservation of infrastructure.
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