Photo Credit: Urek Jurek Wyder
| Key Facts |
| Bridge Name | Facility Carried / Feature Intersected | Location | Structure Type | Construction Date / Builder or Contractor | |
|---|---|---|---|---|---|
|
Pont de Québec
Quebec Bridge | QC-175 and Railroad (Canadian National) Over St. Lawrence River | Québec City and Lévis: Capitale-Nationale, Québec and Chaudiére-Appalaches, Québec | Metal Pinned Cantilever Through Truss, Stationary | 1919 By: Ralph Modjeski |
| Technical Facts |
| Rehabilitation Date | Main Span Length | Structure Length | Roadway Width | Main Spans | Approach Spans |
| 1800 Feet (549 Meters) | 3239 Feet (987 Meters) | 94 Feet (29 Meters) | 3 |
We (HistoricBridges.org) are looking for additional large size digital photos of this bridge to expand the photo gallery. We are looking for both photos that show the whole bridge and also photos that show the details and parts of the bridge. We are interested in photos taken both beside of the bridge and also from on the bridge itself. There are not enough photos of this bridge available on the Internet. We hope you will contact us and send us photos. We will credit you for the photos that we put in the photo gallery.
This bridge is one of the most important and impressive bridges in the world. When this bridge was built it broke the world record for the largest cantilever span, and to this day the bridge is still the longest cantilever span in the world. It will probably never lose this recognition since metal truss bridges and cantilever bridges are not built anymore today. Cable stayed bridges and pre-stressed concrete bridges may continue to break records and knock one another off the record charts as the years go by, but Pont de Québec will continue to stand as the longest cantilever truss bridge ever built. The bridge is recognized as an International Historic Civil Engineering Landmark and is a National Historic Site of Canada.
Pont de Québec is today a lasting monument that with continuous preservation should stand for centuries to come. However this was not always the case. The first attempt to build a bridge at this location was undertaken by the Phoenix Bridge Company, the same company who fabricated the famous Phoenix column bridge compression members in the late 1800s. Their attempt to build a cantilever truss bridge failed, and resulted in a terrible bridge collapse that killed many people. It was perhaps one of the most tragic chapters in the history of the Phoenix Bridge Company, which was otherwise an excellent and noteworthy bridge company. One of the decorative finials from this first bridge is reported to be standing in a cemetery in Saint-Romuald at the foot of the grave of a man killed in the accident. This finial is important as a remnant of this first bridge and a memorial to one of the worst bridge disasters in history.
The second attempt to build a bridge here resulted in the cantilever truss bridge standing today. However, even the second attempt was not without disaster. When the center suspended span was being lifted into place, an accident resulted in the suspended span falling, and killing a number of people. The rest of the bridge was not destroyed however, and the next attempt to place a new suspended span succeeded, completing the bridge that stands today. Ralph Modjeski, a famous engineer who designed the second bridge, wanted to be certain that his bridge would not meet the fate of the first bridge. He did this by making the members of the bridge very massive.
Modjeski's caution in designing the bridge is evident in how massive this bridge is. The shear size and complexity of this bridge is incomprehensible. Some of the tension members on this bridge contain no less than twelve parallel eye bars! The a-frame portal bracing on this bridge is enormous. A single beam of the portal bracing is nearly as wide as a whole car. A number of members are so large and massive that they feature two rows of lattice instead of the more common single row. The top chord of this bridge is so large that it looks like three members lined up side by side. The network of sway bracing above the roadway on this bridge is infinitely complex. There are so many braces and trusses composing this bridge that when the bridge is crosses it often feels much more like a tunnel rather than a bridge. An additional sense of the mass of this bridge is created by its diamond-shaped cantilever towers that includes trusses below the deck as well as above. This is a less common design of cantilever bridge, since most through truss cantilever bridges feature trusses only above the deck. In this sense, Pont de Québec is actually a hybrid, with both through and deck truss characteristics. Finally, the central suspended span of this bridge is a structurally independent feature, a large Pennsylvania "Petit" truss which is massive and large in its own right. This suspended span is itself 195 meters (640 feet) in length. On its own, it is among the longest remaining simple truss bridge spans that are older than 1950. The suspended span displays a different bracing configuration which is easy to see when crossing the bridge.
This bridge was originally built for railway traffic. The bridge is open to vehicular, pedestrian, and also railway traffic. An unusual fact is that despite carrying highway traffic, this bridge is actually owned by the railways, specifically, Canadian National. However, this privately owned bridge does receive public funding for maintenance from the government.
