Bridges are some of the most common architecture in the world today, but their innovation comes from thousands of years of discovery. A bridge can be as simple as a log across a stream or as complex as a massive metal structure spanning an entire river.
The Millau Viaduct is the tallest vehicular bridge in the world. It took 17 years to plan and build this bridge, and it was finally completed in 2004. This bridge, located in France, connects Paris and Perpignan. Commuters say that this route saves more than an hour off the trip, as well as toll money.
The Glenfinnan Viaduct is a railway viaduct. It is quite iconic and has been featured in fantastical movies. The view from this viaduct is breathtaking. The running train often pauses for travellers to take pictures and admire the view .
Bridges are usually a single layer, but double-decked bridges are common in some parts of the world. The George Washington Bridge is a double-decked suspension bridge in New York. It is considered to be the busiest bridge in the world. More than 250,000 cars use this bridge every day!
The Quebec Bridge located in Canada is the world's largest cantilever bridge. It stands at 987m. It was completed in 1919, 30 years after initial construction, and it cost many lives in the process. It was thought to be a huge engineering feat.
The Kinsol Trestle in Canada is one of the tallest rail trestles in the world. Its completion dates back to 1920 and it was primarily built by farmers and loggers. This trestle encompasses a lot of Canadian history, dating back to its early resource extraction days.
There are many suspension bridges across the world. The Pearl Bridge in Japan is the longest in the world, spanning 1,991m! This gigantic construction has the longest central span of any bridge in the world. A span is the distance between two beams or support structures. This bridge is used by about 23,000 cars per day!
Not all bridges are for cars. The Henderson Waves in Singapore is for pedestrians only; it is a footbridge. It's the highest pedestrian bridge in Singapore, at 36 meters from the road below. It connects two major parks and is a favourite for walkers and joggers every day. The curved wooden walls give shelter from the sun during the day.
Most bridges are made of concrete, wood, or metal. They are designed to help humans cross natural rivers, but in the process they can take away from the natural beauty around them. They can also disrupt the natural terrain. Living bridges do the exact opposite. They are not constructed from man-made materials.
Instead, they are made entirely from living plant roots. Local residents of the area carefully and patiently grow strangler figs and tend to them to make them grow in a certain direction. Over generations, these strangler figs have reached the other side of the river. These plants are still growing! It is their deep, living roots that will keep the bridges strong for centuries.
Have you ever been worried or concerned about the safety of these structures? We have structural engineers to thank for these different kinds of bridges. They plan and design these structures and ensure they are safe for the public. Engineers in Canada often graduate from engineering school with an Iron Ring ceremony. The Iron Ring symbolizes the professionalism and responsibility that these engineers must uphold. They have a duty to design and build safe structures for all.
Bridge monitoring systems are also put in place. They keep track of movements and any structural changes to the bridges. The system can identify any points that need repair, which contributes to the overall safety of the bridge.