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The Phoenix Company�s chief engineer had stated that the chord members were carrying �much less than maximum load.�In the meantime, McLure was meeting with Cooper in New York. Of 38 Caughnawaga Mohawk ironworkers who had left their village to work on the bridge, 33 were killed and two were injured (p. 84, Middleton, 2001).The Governor General of Canada formed a Royal Commission, comprised of three civil engineers, whose sole task was to investigate the cause of the collapse. The Quebec Bridge was twenty years in the making, from the founding of the Quebec Bridge Company in 1887 to the bridge�s collapse in 1907. wide at its narrowest section. It wasn’t until Cooper received the drawing that he noticed that the estimated weight of the span was off, on the low side, by almost eight million pounds. �A Disaster in the Making.� American Heritage of Invention and Technology, Spring 1986, 10-17.ASCE Technical Council on Forensic Engineering (TCFE)9201 University City Blvd., Charlotte, NC 28223-0001 The only reason given for this decision was in a note from Hoare to Cooper stating, �the moral effect of holding up the work would be very bad on all concerned and might also stop the work for this season on account of losing the men.� Two days later, news of the matter reached the Phoenixville office and the project superiors there met and discussed the problem. Compression tests were performed on one-third scale models of the compression chords in November 1907 and January 1908 to verify this theory. Earlier, noted French engineer Gustave Eiffel had considered the problem and found that a cantilever design would be superior to either a suspension or an arch bridge for the Quebec site (pp. Both men presumed that the relatively small deflections had occurred due to a pre-existing condition.
92-94.Engineering Record (ER). Another incident had occurred during the 1905 construction season, when chord A9L was dropped and bent while being handled in the storage yard. Some of the key players in the construction and failure of the bridge are listed in Table 1.Table 1. McLure had assured Cooper that he would wire the information to the site on his way to the Phoenixville office. The stress calculations were based on the 487.7 m (1,600 ft) span dimension. I have evolved another theory, which is a possible if not the probable one. As stated by (Middleton 2001, p. 91), ��the thoroughness and objectivity of their inquiry and report stand even today as models of their kind.�The immediate cause of failure was found to be the buckling of compression chords A9L and A9R. John Deans continued to serve as chief engineer of the Phoenix Bridge Company. The Quebec Bridge collapse: a preventable failure (part 1). The Structural Engineer, pp.20-21. 55, January 12, pgs. The basic configuration of a cantilever bridge is shown in figure 1. However, the Phoenix Bridge Company refused to sign a contract with the Quebec Bridge Company due to the financial provisions, which left the bridge company open to considerable risk. B. On June 19, 1903, a final contract was entered into between the two companies, and the name of the Quebec Bridge Company was changed to the Quebec Bridge and Railway Company (pp. With a site selected, bridge design proposals poured in (p. 26, Middleton, 2001).On June 16, 1897, the chief engineer of the Quebec Bridge Company wrote to a friend, who was also the president of the Phoenix Bridge Company (Holgate et al., 1908). 55, January 26, pgs. Thirteen workers lost their lives in this accident. They were then reviewed by Mr. Cooper.
None however, was affected as much as the families of the ones who died and Theodore Cooper.
�The Quebec Bridge Superstructure Details, Part VIII,� (1907), The Engineering record, building record and the sanitary engineer. The top 5.8 m (19 ft.) of each pier was made of solid granite. The Quebec Bridge (Pont de Québec in French) is a road, rail and pedestrian bridge across the lower Saint Lawrence River between Sainte-Foy (since 2002 a western suburb of Quebec City) and Lévis, Quebec, Canada.The project failed twice, at the cost of 88 lives, and took over 30 years to complete.
Another advancement was the formation of two organizations, the American Institute for Steel Construction in 1921, and the American Association of State Highway and Transportation Officials in 1914. A recent review of the history of the bridge and the two collapses was written by Middleton (2001).The St. Lawrence River was the main channel of trade for Quebec during the summer. The engineers on site argued among themselves as to the cause. Following this meeting, Schreiber revised his recommendation to eliminate the need to hire an additional project consultant. Weights were then recalculated from the new information. The top and bottom chords for the anchor and cantilever arms of a bridge were typically designed as straight members. The eyebars formed major tension members in the top chords. Mr. Cooper was an independent consultant operating out of New York City. Bridge specifications were improved after this collapse (Shepherd and Frost, 1995). When the miscalculation of the dead load was identified, the measures taken to re-analyze the structure were not adequate. The official report attributed the collapse to a number of reasons. The specifications called for a cantilever structure. Schneider wrote in his report, which was published as an appendix to the Royal Commission Report, �If a column is made up of several shapes or parts, they have to be connected in such a manner that they will act as a unit. Although at the time the repair was thought to be satisfactory, this member was later found to be the triggering cause of the collapse.Cooper, although the most experienced, seemed to be the most confused by the problem.