The Quebec Bridge

A monumental work on bridge-building in Quebec

The Quebec Bridge over the St. Lawrence river : near the City of Quebec, on the line of the Canadian National Railways ; 1908 - 1918 ; report of the Government Board of Engineers / Department of Railways and Canals Canada. [Ottawa, Ont.] : printed by order of the Governor-General in Council, [1919]. 2 volumes : illustrations, maps ; 31 x 39 cm

Near Quebec City, the St. Lawrence River is more than a kilometer wide and 60 meters deep. Building a bridge at this point is a very challenging task. The first bridge here collapsed spectacularly on 29 August 1907. After various setbacks, the second bridge was completed in 1918. The Quebec Bridge was documented in an extensive final report of the engineers, which the Iron Library has now acquired.

We reprint the following description of the book by courtesy of the antiquarian bookseller Jonathan A. Hill (New York City) , from whom the Iron Library acquired the volume.

The first bridge

Quebec Bridge

The Quebec Bridge, spanning the St. Lawrence about nine miles above Quebec, replaced an earlier structure designed by Thomas Cooper in 1900 to carry the railway over the river. On 29 August 1907 it collapsed without warning in a matter of only fifteen seconds, killing several men and making bridge history as the most spectacular structural failure to that time. A photograph of the ruins shows the entire bridge virtually unrecognizable as such, the structure compressed into a compact mass of steel spaghetti.

As a result of the investigation, the detailing of compression members in particular and bridge engineering in general were raised to a much higher level of scientific analysis and design.

The second bridge

Quebec Bridge

The second bridge, designed by Ralph Modjeski and completed in 1917, was its successor. A cantilever structure, it was based on the Forth Bridge, and it too had its problems. The 5000 ton center span collapsed into the river on 11 September 1916 as it was being hoisted vertically into position. One of the photographs in the book shows it at the precise moment when it struck the water. A new span was successfully lifted almost exactly a year later, the final pins being driven in on 20 September 1917. On 17 October the first train crossed the bridge; a regular freight service began on 3 December; and on 22 August 1919 the bridge was formally opened by the Prince of Wales. With a span of 1800 feet between the two main piers it was the largest of its kind in the world.

The book: «Report of the Government Board of Engineers»

Quebec Bridge

This is the final report of the Board of Engineers, headed by Ralph Modjeski, and it forms the definitive account of the bridge, with a survey of the historical background and the story of the earlier structure, followed by all the technical information of the new one. The text is amply supported by the working drawings and many excellent photographs of the earlier bridge, the two disasters, progress of construction, first train crossing, the official opening etc.