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Quebec Bridge
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The Quebec Bridge (Pont de Québec in French) in Canada crosses the lower Saint Lawrence River to the west of Quebec City, and Lévis, Quebec.
The Quebec Bridge is a riveted steel truss structure and is 987 metres (3,239 ft) long, 29 m (94 ft) wide, and 104 m (340 ft) high. Cantilever arms 177 m (580 ft) long support a 195 m (640 ft) central structure, for a total span of 549 m (1800 ft), the longest cantilever bridge span in the world.
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Encyclopedia
The Quebec Bridge (Pont de Québec in French) in Canada crosses the lower Saint Lawrence River to the west of Quebec City, and Lévis, Quebec.
The Quebec Bridge is a riveted steel truss structure and is 987 metres (3,239 ft) long, 29 m (94 ft) wide, and 104 m (340 ft) high. Cantilever arms 177 m (580 ft) long support a 195 m (640 ft) central structure, for a total span of 549 m (1800 ft), the longest cantilever bridge span in the world. It is the easternmost (furthest downstream) complete crossing of the Saint Lawrence.
The bridge accommodates three highway lanes (none until 1929, one until 1949, two until 1993), one rail line (two until 1949), and a pedestrian walkway (originally two); at one time it also carried a streetcar line. It has been owned by the Canadian National Railway since 1993.
History
Background
Before the Quebec Bridge was built, the only way to travel from the south shore of the St. Lawrence in Levis to the north shore at Quebec City was to take a ferry. As far back as 1852 a project for a bridge over the St. Lawrence River at Quebec was considered, and again, in 1867, 1882, and 1884.
A March 1897 article in the Quebec Morning Chronicle noted:
The bridge question has again been revived after many years of slumber, and business men in Quebec seem hopeful that something will come of it, though the placing of a subsidy on the statute book is but a small part of the work to be accomplished, as some of its enthusiastic promoters will, ere long, discover. Both Federal and Provincial Governments seem disposed to contribute towards the cost, and the City of Quebec will also be expected to do its share. Many of our people have objected to any contribution being given by the city unless the bridge is built opposite the town, and the CHRONICLE like every other good citizen of Quebec would prefer to see it constructed at Diamond Harbor, and has contended in the interests of the city for this site as long as there seemed to be any possibility of securing it there. It would still do so if it appeared that our people could have it at that site. A bridge at Diamond Harbor would, it estimated, cost at least eight millions. It would be very nice to have, with its double track, electric car track, and roads for vehicles and pedestrians, and would no doubt create a goodly traffic between the two towns, and be one of the show works of the continent.
First design and Collapse of August 29, 1907
The Quebec Bridge was included in the National Transcontinental Railway project, undertaken by the federal government.
By 1904, the structure was taking shape. However, preliminary calculations made early in the planning stages were never properly checked when the design was finalized, and the actual weight of the bridge was far in excess of its carrying capacity. The dead load was too heavy. All went well until the bridge was nearing completion in the summer of 1907, when the local engineering team under Norman McLure began noticing increasing distortions of key structural members already in place.
McLure became increasingly concerned and wrote repeatedly to supervising engineer Theodore Cooper, who at first replied that the problems were minor. The Phoenix Bridge Company officials were claiming that the beams must already have been bent before they were installed, but by August 27 it had become clear to McLure that this was wrong. A more experienced engineer might have telegraphed Cooper, but McLure wrote him a letter, and then went to New York to meet with him on August 29, 1907. Cooper then agreed that the issue was serious, and promptly telegraphed to the Phoenix Bridge Company: "Add no more load to bridge till after due consideration of facts." The two engineers then went to the Phoenix offices.
But the message had not been passed on to Quebec, and now it was too late. That same afternoon, after four years of construction, the south arm and part of the central section of the bridge collapsed into the St. Lawrence River in just 15 seconds. Of the 86 workers on the bridge that day near quitting time, 75 were killed and the rest were injured. Of these victims, 33 (some sources say 35) were Mohawk steelworkers from the Kahnawake reserve near Montreal; they were buried at Kahnawake under crosses made of steel beams.
It is commonly, but falsely, rumored that the iron and steel from the bridge collapse that could not be reused for construction was used to forge the early Iron Rings worn by Canadian Engineers starting in 1925.
Second design and Incident of September 11, 1916
After a Royal Commission of Inquiry into the collapse, construction started on a second bridge. Three engineers were appointed: H.E. Vautelet, a former engineer for the Canadian Pacific Railways, Maurice FitzMaurice from Britain, who worked on the construction of the Forth Bridge, and Ralph Modjeski from Chicago. Vautelet was President and Chief Engineer. The new design was still for a bridge with a single long cantilever span, but a much more massive one.
On September 11, 1916, when the central span was being raised into position, it fell into the river, killing 13 workers.
Completion
Construction was ultimately completed in August 1917, at a total cost of $25 million and 89 bridgeworkers' lives. On December 3, 1919, the Quebec Bridge opened for rail traffic, after almost two decades of construction. Its center span of 549 meters (1800 ft) remains the longest cantilevered bridge span in the world and is considered a major engineering feat.
Post-completion history
The bridge was built and designed primarily as a railway bridge, but the streetcar lines and one of the two railway tracks were converted into automobile and pedestrian/cycling lanes in subsequent years. In 1970 the Pierre Laporte Suspension Bridge opened just upstream to accommodate freeway traffic on Autoroute 73.
The Quebec Bridge was declared a historic monument in 1987 by the Canadian and American Society of Civil Engineers, and on January 24, 1996, the bridge was declared a National Historic Site of Canada.
The bridge was built as part of the National Transcontinental Railway, which was merged into the Canadian Government Railways and later became part of the Canadian National Railway (CN). The Canadian Government Railways company was maintained by the federal government until 1993, when a Privy Council order dated July 22 authorized the sale of Canadian Government Railways to the Crown corporation CN for one dollar (CAD). On this date, the Quebec Bridge also came under complete ownership of CN. CN was privatized in November 1995, making the bridge privately owned.
Despite its private ownership, CN receives federal and provincial funding to undertake repairs and maintenance on the structure.
Aftermath
In Canada, and many other countries, the aftermath of the Quebec bridge scenario still affects many today. This disaster showed what unquestionable power an engineer had in a project. This led many to question this power. Engineers worried about government intervention acted on their own and founded multiple independent engineering groups.
Eventually these groups formed together in their respective areas and created what are now recognized as organizations of Professional Engineers. P.Engs are under different rules and regulations based on the organization to which they belong. General guidelines include that an engineer must pass an ethical examination, be able to show good character through the use of character witnesses, and have applicable engineering experience (in Canada this constitutes a minimum of four years' practice under a certified Professional Engineer).
A recent ceremony for the lives of the 33 Mohawk casualties was held in the Kahnawake Reserve where a statue resembling part of the bridge and a plaque was unveiled.
See also
External links
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