The chief conclusions of the royal commission, appointed by the Canadian government to investigate the cause of the failure of the Quebec Bridge, which collapsed on August 29, 1907, have been submitted to the Canadian Parliament. The summary of the findings of the commission are as follows:
A. The collapse of the Quebec bridge resulted from the failure of the lower chords in the anchor arm near the main pier. The failure of the chords was due to their defective design.
B. Stresses that caused the failure were not due to abnormal weather conditions or accident, but were such as might be expected in the regular course of erection.
C. The design of the chords that failed was made by P. I. Szlapka, the designing engineer of the Phoenix Bridge Co.
D. This design was examined and officially approved by Mr. Theodore Cooper, consulting engineeer of the Quebec Bridge & Railway Co.
E. The failure cannot be attributed directly to any cause other than errors In judgment on the part of these two engi neers.
F. These errors of judgment cannot be attributed either to lack of common professional knowledge, to neglect of duty or to a desire to economize. The ability of the two engineers was tried in one of the most difficult professional problems of the day and proved to be insufficient for the task.
G. We do not consider that the specifications for the work were satisfactory or sufficient, the unit stresses In particular being higher than any established by past practices. The specifications were accepted without protest by all interested.
H. A grave error was made in assuming the dead load in the calculations at too low a value and not afterwards revising this assumption; This error was of sufficient magnitude to have required the condemnation of the bridge even if the details of the lower chords had been of sufficient strength, because, if the bridge had been completed as designed, the actual stresses would have been considerably greater than those permitted by the specifications. This erroneous assumption was made by Mr. Szplaka and accepted by Mr. Cooper and tended to hasten the diaster.
I. “We do not believe that the fall of the bridge could have been prevented by any action that might have been taken after August 27, 1907. Any effort to brace or take down the structure would have been impracticable, owing to the manifest risk of human life involved.
J. The loss of life in August. 1907, might have been prevented by the exercise of better judgment on the part of those In responsible charge of the work for the Quebec Bridge & Railway Company and for the Phoenix Bridge Company.
K. The failure on the part of the Quebec Bridge & Railway Company to appoint an experienced bridge engineer was a mistake. This resulted In a loose and inefficient supervision of all parts of the work on the part of the Quebec Bridge & Railway Company.
L. The work done by the Phoenix Bridge Company in making the detail drawings and in planning and carrying out the erection, and by the Phoenix Iron Company in fabricating the material was good, and the steel used was of good quality. The serious defects were fundamental errors in design.
M. No one connected with the general designing fully appreciated the magnitude of the work nor the Insufficiency of the data upon which they were depending. The special experimental studies and investigations that were required to confirm the judgment of the designers were not made.
N. The professional knowledge of the present day concerning the action of steel columns under load Is not sufficient to enable engineers to economically design such structures as the Quebec bridge. A bridge of the adopted span that will unquestionably be safe can be built, but in the present state of professional knowledge a considerably larger amount of metal would have to be used than might be required if our knowledge were more exact.
O. The professional record of Mr. Cooper was such that his selection for the authoritative position that he occupied was warranted, and the complete confidence that was placed In his judgment by the officials of the Dominion government and the Phoenix Bridge Company was deserved.
—An account in the October, 1907 issue of Machinery of the widely reported and shocking destruction of the Quebec Bridge, which was built as a part of National Transcontinental Railway Project. The disaster and the loss of life has been suggested as the inspiration for Cather’s novel.