The Bridge of Quebec During its 30-year construction, the Quebec Bridge in Quebec City collapsed twice. In 1907, 75 employees were killed and 11 were injured when the bridge fell due to a design flaw that was subsequently proved to be insufficient to hold its own weight. In 1948, another bridge was built over the same site as a replacement for the former one. This new structure also collapsed, killing 43 people.
In total, the Quebec Bridge has been destroyed three times. The first two incidents led to major disasters that killed many people. The third collapse happened several years ago and it was not as serious.
Each time the bridge has collapsed, officials have said that they were surprised by how many people were on the bridge at the time of the accident. A lot of people go across the bridge each day to work or school, so this fact shows just how dangerous this place is even with a new bridge built over the same spot.
After the first two incidents, changes were made to make the bridge safer for pedestrians. For example, guard rails were put in place to prevent people from falling off of the side of the bridge. Also, steps were added to some of the towers where people could get out of the rain or snow if it started falling. These changes helped but they were not enough to prevent more deaths on the bridge.
However, at 5:37 p.m. on August 29, 1907, just as the Phoenixville convention was wrapping up, the Quebec Bridge collapsed. The south anchor arm, cantilever arm, and half constructed suspended span all collapsed 150 feet into the St. Lawrence River in less than 15 seconds. The loss of life was relatively light with only two people killed that day. However, because of the unstable nature of the bridge, it took more than a month for investigators to determine what caused the collapse.
The Quebec Bridge is an international bridge that connects Montreal, Quebec, with Pointe-Claire, a suburb of Montreal. It has three parallel spans over the Saint Lawrence River, each about half a mile long. The main span crosses from Montreal's Island South of the river to Pointe-Claire on the north shore. It is one of the world's longest cable-stayed bridges, with a length of 2.5 miles (4.0 km).
Construction began in February 1905 and was completed in October 1908 at a cost of $7 million ($100 million in 2007 dollars). At the time of its construction, it was considered to be one of the most expensive public works projects in history. The bridge opened for traffic the next year on January 7, 1909. It was designed by Thomas Casey Jr. and Robert Montgomery Bird of the United States, and Henry Fox & Sons of London.
Over the last decade, more than 60 bridges have fallen throughout the world. And, as investigators in Italy look for the cause of Polcevera's single-point failure, survivors of bridge collapses tell the harrowing story of the day the road gave way and they fell into the nothingness.
Read about these disasters below.
April 2013: Moria Bridge, Greece
The new Moria Bridge was opened in February 2003 over the Mediterranean Sea port of Piraeus. But only three years later, on April 11, 2006, it collapsed during a heavy rainstorm killing 22 people and injuring dozens more.
The 930-foot (290-meter) bridge was the first in Greece to be built using modern materials instead of traditional methods. It had two parallel tubular steel trusses with concrete girders as supports. After the collapse, an official report concluded that the main cable of the bridge was damaged by ice when it was still under construction. This led to its collapse during the storm.
May 2012: Pontiac River Raisin Memorial Bridge, Michigan
The Pontiac River Raisin Memorial Bridge is a four-lane divided highway bridge that crosses the Pontiac River between Warren and Lincoln townships in Oakland County, Michigan. It connects I-75/I-96 to Telegraph Road (former M-52).
Bridge collapses may be devastating incidents, resulting in fatalities and significant property damage. As a result, bridge engineers, designers, and builders must take their duties very seriously at all times. Understanding bridge failures can result in significant improvements in the design, construction, and safety of future construction projects.
When bridges are built, they are not guaranteed to last forever. Over time, the supporting soil beneath them will shift and move, causing stress on the bridge structure. Continued use of the bridge will also put additional strain on the structure.
Sometimes this is what has happened with older bridges. They serve our communities well for many years and then one day they fail when someone drives into a hole hidden under the road. More commonly, though, modern bridges are designed to be safe for hundreds of thousands of miles of travel. When they fail, it is because something bad enough has happened that the remaining portion of the bridge cannot hold its weight. The cause of this event varies but usually involves one of three things: a piece of metal in the lane of traffic breaks off from the rest of the bridge, which falls onto the roadway below; an explosive charge is placed on the bridge by terrorists or criminals hoping to destroy it; or simply poor maintenance by the city over time. In any case, when a bridge fails there is often no warning. You can drive over it and never know what might happen next.
It is estimated that at least 3,000 people died. As if it wasn't enough, portions of the bridge fell on 1281, 1309, 1425, and 1437. The collapse in 1281 was caused by growing ice from the frozen Thames, which physically destroyed five of the arches. This is because they were made of wood, which grows trees about twice as fast as it can be harvested. Thus, the growing bridge over time became heavier than the supporting walls underneath it. In winter, when the river is frozen, this is not a problem but in summer, when there's no ice on the river, this can cause problems.
The next collapse occurred 130 years later in 1837. By then, the city had learned its lesson, so engineers built the bridge with iron arches instead. They would eventually become standard on any new bridge over a frozen river in cold climates.
Almost a hundred years later, in 1966, another part of the bridge collapsed due to heavy traffic. This time, more than just bricks and mortar were damaged, resulting in one death and 13 injuries. The British government ordered an investigation into the stability of the bridge, which resulted in some changes being made. For example, wide bands of metal were added to the sides of the bridge to help it withstand future pressure from large vehicles.
Finally, in 2009, yet another portion of the bridge collapsed due to overweight trucks driving too close together.