Please report promptly regarding joint 7 and 8-L with the facts. In the meantime, the people at the bridge site had been showing a great deal more concern than Cooper or the people in Phoenixville were. Cooper later testified:. I then said to Mr. Cooper sent McLure to Phoenixville. Work continued throughout the day at the bridge site as neither Hoare, Cooper, McLure, Deans nor Szlapka had told them otherwise.
They decided to do nothing until the morning, awaiting A. That decision was made shortly after McLure had arrived around Quebec Bridge August 27, south cantilever. Small traveler on left and large traveler at end of cantilever arm. The shift was to end at with 86 men working on the bridge. There were three riveting crews and one hoisting crew working on the anchor arm, and six riveting crews working on the cantilever arm.
A locomotive had just delivered an eight-ton load of steel to the end of the bridge and was returning with another load of the same size. It was located at just about the end of the cantilever arm near the large traveler when witnesses reported a loud explosion. In no more than 20 seconds, probably less, the massive 17,ton structure just settled downward into the St.
A total of 75 men were killed instantly, with 11 escaping with their lives. Frank Griggs, Jr. He is now an Independent Consulting Engineer. Dec, By Frank Griggs, Jr. ASCE, D.
In Articles , Historic Structures Comments 0. The first in a three part series on the Quebec Bridge. Theodore Cooper. A few months later, it was proven that Cooper had committed basic errors when he had modified his original plans without reviewing his calculations. In , the Canadian government took control of the project.
Under the supervision of a Board of Engineers, rigorous norms were adopted. The original design was improved by developing the new K system of web bracing, deemed sturdier, more elegant and easier to build. Nine years after the first bridge collapsed, the central span was raised while a crowd numbering over gathered to celebrate the event. Unfortunately, tragedy struck a second time when the central span collapsed again: 13 men died, and another 14 were injured.
The cause was determined to be a defective beam. On September 20, , the new central span was successfully installed before a crowd of people from all over Canada and the United States. Lawrence River, as well as provide a link to the American rail network. They looked like bartenders on a picnic. At five-thirty a fitter named Eugene Lajeunesse finished tightening a bolt and remarked to his brother Delphis that it was almost time to quit.
Eugene had no sooner said them than the outer arm of the diamond pointing over the river gave a sudden twitching shudder. A second later it tore free from the stone pier, hurtled down into the deep mid-river ship channel and vanished in a tremendous burst of spray.
At the same time the inner anchor arm, leading back to the shore across the rock-strewn mud, fell with a crash on the rocks and instantly became a pile of twisted steel. Of the eighty-six steelworkers who had been working on the two outstretched arms of the diamond only Eugene and Delphis Lajeunesse and nine others lived through the fall of the Quebec Bridge.
The seventy-five who died made it the worst disaster in the history of bridge building. But there are other ways of measuring a disaster than counting the dead, and the most tragic aspect of this one was that it need never have happened. It could have been avoided as early as if two sets of calculations had been properly checked. Because they weren't, the bridge itself was doomed two years before its death.
Yet much later, almost at the last moment, there were to be three additional chances to save the men it killed. The ominous behavior of two girders should have been taken as an urgent warning to stop building and clear the bridge; it wasn't. One man who might have suspended work on the fatal day decided not to do so because he'd had a comforting dream. And a telegram that could have brought him to his senses w'as first misdirected and then lay neglected during the last five hours before 'the disaster.
That was the end of the first Quebec Bridge on an August afternoon seven years after building on it had started. A second bridge was started as soon as the ruins of the first were cleared away or buried in the river, and the cruel sequence of hope and bitter disappointment was repeated.
When nine more years' work had been done disaster struck again—only a few hours before the last rivets were to be driven—and thirteen more steelmen died. When the Quebec Bridge was finally completed it had taken seventeen years to build and cost eighty-eight lives.
Diagrams show how first the cantilever span top , then centre span middle crashedinto St. The wreckage is still in the river, a grisly tomb for men it killed. The engineers who began it tried to span the St. Lawrence where the river was nearly two thirds of a mile across; almost the whole width had to be kept clear for a ship channel.
To do this meant designing a central span of steelwork that would thrust 1, feet across the water supported by piers on either side of the channel—the longest cantilever span ever built. But at the turn of the century a bridge linking Quebec City with the trade and commerce of the south shore of the St. Lawrence had become a matter of economic life and death. In the days of sail in the early s Quebec had been the busiest port and biggest city in Canada.
Then the steam engine permitted shipping to negotiate the narrowing, more turbulent river for another two hundred miles to Montreal. Quebec City went into a deepening slump. A transfusion of trade by train and wagon from across the river was needed to help its hard-hit commerce. For almost forty years a series of proposals to build a bridge was offered, all of them abortive. Then for ten years they stalled while looking for assurance that there would be enough traffic to pay them a profit.
At the same time they were looking for an engineering name sufficiently large to stand behind such a vast undertaking. Flattered at the idea of building the biggest span in the world, Cooper said yes.
Promptly, they let the contract for stonework. In October the company laid the cornerstone of the first pier. Soon after, it realized that much more money would be needed to put steel on the piers. It was at this fortuitous moment that the federal government decided to build a transcontinental railway. It needed a bridge near Quebec City to link the new line with the Grand Trunk and Intercolonial lines across the St Lawrence and thus offered to underwrite 56, Plans for the steelwork had been drawn by the chief designer of Phoenix.
His problem, besides leaving the whole midriver channel clear for shipping, was to make sure even big liners could steam under the bridge without knocking off the lops of their masts. This meant the bottom girders had to be a hundred and fifty feet above the water. Sziapka also had to provide for two railroad tracks, two streetcar tracks and two roadways. To do all this he designed a bridge sixtyseven feet wide and 2, feet long, not counting the approaches.
The cantilever span needed to keep the channel clear was 1. The principle of the cantilever is simply that of a beam or framework supported ut one end and carrying a load at the other unsupported end. An arm from each pier jutted outward above the river to be linked to its opposite number by a span in the centre. With its lacework of supporting steel each cantilever, stretching from shore to pier and from pier toward midstream, had the approximate shape of a diamond with its fat width resting on a pier.
The federal government suggested that its expert, Collingwood Schreiber, who was chief engineer of the Department of Railways and Canals, also okay the plans. But Cooper replied angrily that this was an affront to his reputation, so the government backed down. By the spring of working drawings for the project—the minute, step-by-step blueprints covering every phase—were ready. It now became possible to calculate to the pound the weight of the cantilevers—the weight of the arms stretching out from the piers on each side of the channel.
If a comparison had been made it would have shown that the real weight of the two outstretched arms of each cantilever was about eight million pounds more than had been estimated. On July 22, , without further investigation, the first girder was bolted to its stone pier on the south side of the river.
When they did he spotted the difference in weight almost at once. But by then six sections of the anchor or inner arm of the cantilever had been erected. He was faced with a bitter choice. He knew there was a hideous danger the overloaded anchor arm would fail: on the other hand there were two factors that inclined Cooper to take the risk: his heart was set on being known as the man chiefly responsible for having built the greatest bridge in the world. Two years earlier his health had failed and his doctor had forbidden him to leave New York.
Cooper had pointed out to the directors of the bridge company that this meant he could never visit the bridge while it was being built and would have to rely on reports from engineers on the spot—a most unsatisfactory arrangement and reason enough for the directors to get a younger and more active man to replace him. But when they urged him to stay on. The second thing in favor of taking the risk was that the federal government wanted the bridge finished by the summer of , so it could be formally opened by the Prince of Wales, later George V, when he came to Quebec for the three hundredth anniversary of the founding of the city.
Cooper wanted that too, because he felt that having his bridge opened by the heir to the British throne would add the supreme toueh of distinction. During the season of and for the first couple of months of the season, as far as Cooper could tell from the reports he got.
Then on June 15, , Norman McLure, the inspecting engineer at the bridge, wrote Jo say that two girders of the anchor arm were a quarter of an inch out of alignment. It is not serious. Early in August, McLure wrote that the two girders had gone a fraction of an inch farther out of alignment since his June report; they also appeared slightly bent.
Cooper was disturbed, and asked McLure for fuller details and an explanation of how the bending had occurred. But his inspector on construction. Kinloch, took a different view.
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