Henri Bourassa Bridge, Montréal
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news N°16 2008 Headlines Editorial L. Crépeau B. Hodac OSMOS expertise available throughout Canada Owing to the enormous distances and extreme climatic conditions Henri Bourassa Bridge, Montréal: prevailing in Canada, the state of our highway network and of Closed for safety reasons? – No, open and safe! its thousands of civil engineering structures is of prime importance. After the collapse of the Concorde The Henri Bourassa bridge was built in 1938 “OSMOS Canada has carried out the work to our overpass in September 2006, the and original construction plans were not available. entire satisfaction, not only in terms of budget Johnson Commission outlined very Based on traditional visual inspection and and schedule, but also of the unusual character precise guidelines relating to the testing techniques, and material testing, bridge of the solution recommended. In fact, as a direct maintenance of the highway network traffi c was limited to automobile loads (maximal result of the loading tests and the continuous in Québec and the methods to be used. In order to ensure that the load: 5 tons). monitoring of the Henri-Bourassa viaduct, structures are safe, it is necessary we were able to open it to truck traffi c.” to develop a process that depicts Using actual, measured, dynamic and static Paul Laberge, City of Montréal the actual structural behaviour results, integrated into a fi nite element numerical based on objective and verifi able model, OSMOS technology supplied information criteria. To date, only OSMOS is permitting to safely raise the bridge’s assessed able to satisfy all the points in the bearing capacity to 38 tons. increasing requirement for safety. Owing to OSMOS, the 6 policemen who oversaw OSMOS technology was so successful access to the structure were no longer necessary. in Canada, that it is hardly surprising that a few months later, a company dedicated to marketing OSMOS expertise was created: Contents OSMOS Canada Inc. We have pleasure in introducing Safety • Stukely Bridge: No detours, thanks to OSMOS our new team (see page 4) which • Bridge No. 07191, Coaticook: where traditional evaluation has its limits is now at the service of owners of • Frontenac Bridge, Sherbrooke: To be, rather than to appear … safe structures and ready to aid them in the challenge entailed by rendering Surveillance • Odellach Bridge, New Brunswick: Reliable data, even in extreme temperatures engineering Canada’s structures safe and ready • Five Fingers Bridge, New Brunswick: A structural health record for long-lasting protection for use. • Williams sewer, Montreal: How long can it be blamed? Louis Crépeau, Chief Executive Offi cer, OSMOS Canada • Johnson Commission report: What are the lessons? OSMOS CANADA Inc. • OSMOS Canada: A team up to the challenge Bernard Hodac, • Testimonials Chairman and CEO, www.osmos-group.com | 01 OSMOS group Safety It is difficult to evaluate this thick concrete slab bridge, with a 54° angle of skew, and numerous bending cracks, by means of traditional methods. Owing to doubts about its safety, the experts had no alternative but to close the bridge. But, in fact, it benefited the local population for it to remain open. OSMOS technology removed doubts about the bridge’s behavior, so that eventually it was reopened to automobile traffic. The bridge is monitored day and night through a series of Optical Strands and a related surveillance Stukely Bridge: service, which reassures the client about his No detours, thanks to OSMOS responsibility towards the local community in the knowledge that the bridge is totally safe. Safety Bridge No. 07191, Coaticook: Where traditional evaluation has its limits! Built in 1922, this Pony-Warren truss bridge 6 Optical Strands connected to a monitoring evaluating the bridge’s bearing capacity. across the Coaticook River is vital for access station ensure its continuous surveillance for safety OSMOS expertise allows for the long-term to the town centre of Coaticook. It is of the purposes. With heavy truck traffic in excess of monitoring of the bridge, so that the client Pony-Warren type in steel. 200 vehicles/day and many years of operation, can select when to repair it and what work the client cannot afford to make any mistakes in to carry out. Safety Frontenac Bridge, Sherbrooke: To be, rather than to appear … safe! Built in 1932, the Frontenac viaduct structure’s OSMOS technology, fitted into the structure, has possible to record the structure’s behaviour, headroom is not very high. shown beyond doubt that the structure behaved ensuring that it is correct, even after collisions Over time, numerous trucks, unable to pass normally, and that it‘s behaviour remains within with oversize vehicles. owing to the low headroom, have collided into its elastic range under normal service loads. the structure, so that it looks unsafe. Through the surveillance system, it will be www.osmos-group.com | 02 Surveillance engineering Odellach Bridge, New Brunswick – Many civil engineering structures in our national network are well advanced in Reliable data, even in extreme temperatures terms of their useful life. Entrusting OSMOS with a loading test, the client requested a real image of the structure’s quality. Through the test, it was possible to evaluate the structure’s bearing capacity. Such test will be carried out on all the bridges managed by the client.During the first year, the client plans to begin by drawing up a structural health record of about 100 bridges, through rotating the use of 10 mobile monitoring stations. This procedure, which is simple and inexpensive, will make it possible to select those structures which require continuous monitoring. Surveillance engineering The technical challenges relating to monitoring Five Fingers Bridge, this structure are similar to those of the Odellach Bridge: acquiring relevant information, simple New Brunswick – systems installation and no effects on traffic operations. A structural health record for long-lasting protection Thanks to 3 types of alarms, the OSMOS system ensures that the structure is safe for use at all times: The client witnessed the installation and was - static threshold alarm impressed by how user-friendly it is, as well as - dynamic threshold alarm by how reliable it is at very low temperatures - elastic return alarm. (-25°C at time of installation). Surveillance engineering Williams sewer, Montreal: How long can it be blamed? This 300 meters long collector sewer, in the old so that he had to ensure that the capacity is sewer structure’s weak areas and reassure district of Montreal, is the oldest granite block sufficient under the new conditions. the client about its capacity. The client then sewer in North America. authorized the repair work. Calibrated loading trials were carried out to The client wants to refurbish the landscaped follow strains in three points: deformation of Given its importance to Canada’s national area above the sewer, by adding a further 1.2 the vault and side walls and deflection. Analysis heritage, the client also asked OSMOS for meters of soil, the equivalent of a load of 20 kN/m2, of the results made it possible to determine the continuous safety monitoring. www.osmos-group.com | 03 Johnson Commission report Johnson Commission report: What are the lessons? The Johnson Commission, created after the collapse of the de la Concorde Overpass in Montreal ! Defective materials ¸ OSMOS keeps a record of mechanical in October 2006, produced a 1,000-page report. ! Incoherence in the monitoring chain properties The quality of the survey, the relevance of its findings and subsequent recommendations were ! More than once, the relevant departments ¸ OSMOS provides objective information unanimously hailed by all players concerned. We were found to have neglected warning signs ¸ OSMOS detects disorders when they are in give the main points of the report below, all of about the structure’s potential weaknesses their earliest stages which can be resolved using OSMOS technology. ! The structure’s real behavior was not taken ¸ OSMOS establishes a “true model” of a All experts agree that it is difficult, even impossible, into account structure’s behavior on an ongoing basis to foresee catastrophes such as that of the de la Concorde Overpass. But catastrophes are ! Incomplete and irregular records ¸ OSMOS unfailingly keeps a record of a always the result of a sum of failings. The Johnson structure’s life Commission report pointed to 5 main failings in structural maintenance procedures. If OSMOS Ë technology is used, none of these failures are able to develop in such a manner as to cause an unpredictable catastrophe. With OSMOS no structure will ever hold surprises again OSMOS Canada OSMOS Canada: A team up to the challenge Following the rapid success of OSMOS technology Louis Crépeau is well-known in Canada in the when it was introduced into Quebec, OSMOS field of civil engineering. He has often introduced Canada now holds total exclusivity on OSMOS innovative techniques in the construction industry, expertise throughout Canada. for example, fiber reinforced concrete and paraseismic retrofit reinforcements. Under the management of Louis Crépeau, Now, Louis Crépeau and his highly motivated a top-quality technical team is already operational colleagues are certain that they can provide and ready to offer its services to all those who owners of structures with the means of assuming manage structures in Canada, allowing them to their responsibilities and enhancing the quality take advantage of OSMOS’s expertise, of our structural inventory. Canada has made whatever their fields of action or requirements. this challenge a major priority. From left to right: OSMOS CANADA Inc. • T: (514) 788-2075 Philippe Gareau, Jacques Bossé, Louis Crépeau, www.osmos-canada.com • contact: [email protected] Francine Marceau, Chakib Kassem, Albert Belhumeur Testimonials The Champlain Bridge The Champlain Bridge is a vital access route to fitted onto a number of girders in the bridge the large metropolis of Montreal carrying daily since 2005.