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Aiming to surpass the Forth Bridge, the Quebec Bridge and Railway Co. wanted a prestigious designer and hired Theodore Cooper, a prominent American bridge engineer. He would not actually design the structure but would be responsible for those who did.
Under the contract for the Quebec's superstructure, the winning low bidder would design and build it. Phoenix Bridge Co. won the bid. Cooper, who would never actually visit the site, considered Phoenix's design the best and cheapest. The design's two towers resembled the set of three on the Forth Bridge. But the Scottish span was a riveted structure made up of massive tubular members. The Quebec design would be built of pin-connected lattices. Work on the superstructure began in 1905. The shore arms of the bridge were to be built on falsework and the cantilever arms and the two halves of the suspended span were to be built out toward each other with traveler cranes.
On Aug. 29, 1907, as the cantilever' south arm neared mid-channel, it collapsed and crashed into the river, killing 78 men. Engineering News called the collapse the greatest engineering disaster in history (9/5/07 p. 258). It was attributed to buckling of an inadequately braced compression member. A new design, commissioned in 1908, called for a heavier, riveted structure using the new K truss. A 640-ft-long center span would be lifted in place from barges.
By July 1916, both cantilevers were completed. Two months later, tugs pulled the 5,000-ton span to the site and hanger chains from each cantilever arm were attached. By mid-morning, five 2-ft lifts on the north side and six on the south side had been accomplished. Then disaster struck again. One of four rocker arms supporting the span failed, causing a collapse that killed 11 men. A year later, a duplicate span was successfully lifted into place.
NEWS IN BRIEF 1912, 1913
New Welland Canal
The new Welland Ship Canal to be built between Lake Erie and Lake Ontario to replace the current canal will have a depth of 30 ft over thelock sills. The difference in elevation between the two lakes will be overcome by seven lift locks 800 ft in length and 80 ft in width. The total length of the canal will be about 25 miles. (Reported in Engineering News 10/17/12 p. 731)
National Building Code
At the May 21 meeting of the American Society of Civil Engineers, a resolution was adopted by the participants that, in view of the wide divergence of building codes throughout the country, the Board of Direction be authorized and directed to consider the matter of the appointment of a special committee to draw up a national building code. (Reported in Engineering Record 5/24/13 p. 45)
Disturbing Dredging
The Cape Cod Canal construction work is annoying some of the wealthy summer residents at Agawan Point in Buzzards Bay, Mass. A preliminary injunction was requested as part of a lawsuit brought by several prominent residents to restrain the Cape Cod Canal Construction Co. from continuing the work of dredging on the ground that the work disturbs their slumbers and impairs their health. Fortunately, the judge has refused to grant such an injunction. (Reported in Engineering News 8/1/12 p. 230)
What is the Diesel Engine?
It will probably surprise most American engineers, even those posted on the recent progress made abroad in application of the Diesel engine to marine propulsion, to learn there are now 300 vessels equipped with such engines. No development in mechanical engineering since the invention of the steam turbine is of as great importance as construction of the Diesel engine. To this development, the U. S. has contributed absolutely nothing. (Reported in Engineering News 4/4/12 p. 654)
The Channel Tunnel again
Another English Channel tunnel project has been proposed, with two tubes to be constructed, each 18 ft in dia and 36 ft apart on centers, to give through-train connection between London and Paris. (Reported in Engineering Record 8/9/13 p. 44)
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