Suspension bridges are one of the most popular types of bridges in the world. A suspension bridge is a type of bridge that has cables that suspend the deck from towers. The first suspension bridge was built in 1824 by Scottish engineer Thomas Telford. The Bridge was built over the Menai Strait in Wales. The Brooklyn Bridge, which was completed in 1883, is one of the most famous suspension bridges in the world. It spans 1,595 feet (486 meters) and connecting Manhattan and Brooklyn.
Today, there are many different types of suspension bridges. Some are designed for cars and trucks, while others are designed for pedestrians or trains. Suspension bridges can be found all over the world, spanning everything from small creeks to large rivers. They are an important part of our infrastructure and help us to travel and move goods around the globe.
A suspension bridge is one in which numerous cables are stretched between two or more towers, which bear the majority of the bridge weight and force. The cables connect the towers to the anchorages.
The towers are set in the riverbanks and act as abutments. The roadway or deck is suspended from the cables, which also support any vertical loads on the bridge, such as pedestrians and vehicles.
Suspension bridges were first used by the ancient Incas and Mayans in South America, who Suspended ropes or vines across gorges or canyons. The first modern suspension bridge was designed by British engineer James Finley in 1811. The Bridge was never completed, but his design was used for many other bridges.
The longest suspension bridge in the world is currently the Akashi Kaikyō Bridge in Japan, which has a main span of 1,991 meters (6,532 ft). It was completed in 1998.
The Brooklyn Bridge, which opened in 1883 and spans 1,595 meters (5,249 ft), was the longest suspension bridge in the world for over a century.
Suspension bridges are one of the most popular types of bridges because they can be built across very long distances with fewer materials than other types of bridges. They are also very beautiful, which makes them popular tourist attractions.
Suspension bridges have improved our daily lives since John A. Roebling created the suspension bridge design in 1845 and erected the Allegheny Suspension Bridge in Pittsburgh, Pennsylvania. These bridges are superior to previous ones in a variety of ways. Suspension bridges may span greater distances and are far less expensive than beam bridges, which are simply made of beams supporting the deck of the bridge and can’t span as long as these suspension bridges can (“Suspension Bridge”).
Despite their advantages, suspension bridges also have some disadvantages. These bridges are very susceptible to high winds and earthquakes, which can cause the bridge to collapse. In fact, the first major suspension bridge disaster occurred in 1854 when a hurricane hit the Bridge of Sighs in England, causing it to collapse and kill thirteen people (Placzek). Even though suspension bridges may have some disadvantages, they continue to be one of the most common types of bridges today because of their many benefits.
Suspension bridges are made up of two towers that support cables, which in turn support the roadway or deck of the bridge. The cables are attached to the towers at different points and then they cross the towers and are anchored into the ground at different points on each side of the river or valley that the bridge is spanning. The roadway is suspended from these cables by vertical suspender cables or wires (“Suspension Bridge”).
The first suspension bridge was built by James Finley in 1808 over Elk River in Pennsylvania, but it was not a very successful design, as it only lasted around three years before collapsing (Placzek). In 1811, French engineer Jean-Rodolphe Perronet designed and built a suspension bridge over the Seine River in Paris, but it was also not very successful as it only lasted for around seven years before being demolished due to safety concerns (Placzek).
The first major success for suspension bridges came in 1817 when American engineer Samuel Brown designed and built a bridge over the River Wear in England (Placzek). This bridge was much more successful than previous suspension bridges and lasted for around fifty years before being replaced. The Bridge of Sighs in England, built in 1831, was also a successful design and lasted for around twenty years before it collapsed during a hurricane (Placzek).
It was not until 1845 that John A. Roebling designed and built the Allegheny Suspension Bridge in Pittsburgh, Pennsylvania, which was the first suspension bridge to successfully span a large river (Placzek). This bridge was 1,010 feet long and had a main span of 358 feet (Placzek). The Allegheny Suspension Bridge was such a success that Roebling went on to design and build many more suspension bridges, including the Brooklyn Bridge in New York City, which was completed in 1883 and is one of the most famous suspension bridges in the world (Placzek).
The Brooklyn Bridge was built using Roebling’s new wire-rope manufacturing process, which made the bridge’s cables much stronger and allowed them to support a longer span than previous suspension bridge designs (Placzek). The Brooklyn Bridge has a main span of 1,595.5 feet and is one of the longest suspension bridges in the world (“Brooklyn Bridge”).
Suspension bridges continue to be designed and built today. Some of the longest suspension bridges in the world include the Akashi Kaikyō Bridge in Japan, which has a main span of 1,991 feet, and the Xihoumen Bridge in China, which has a main span of 2,222 feet (“List of Longest Suspension Bridges”). These bridges are able to span such long distances because of advances in technology and engineering.
Suspension bridges are an important part of our infrastructure and will continue to be built as we need to span longer distances. They are cheaper than other types of bridges and can span much longer distances. However, they are also susceptible to high winds and earthquakes and need to be regularly inspected and maintained.
The pull forces are transferred through the supporting wires, which run between the two anchorages. The cables running from one anchorage to the next are stretched by the weight of the bridge and its traffic. The soil beneath each anchorage is also under tension, but since they are firmly planted to the ground, it is placed into the ground. To assist stiffening a suspension bridge and limit swinging, most suspension bridges include a truss system underneath the bridge deck.
The Bridge Deck:
The bridge deck is the roadway or walkway of the bridge. It is also what supports the weight of the traffic on the bridge. The deck hangs from the cables and is either suspended by hangers or directly connected to them. In early suspension bridges, like the Brooklyn Bridge, hangers were used. Hangers are metal rods that connect the cables to the deck. The modern tendency, however, is to use eye-bars and suspenders to connect the deck directly to the cables.
The Towers:
The towers of a suspension bridge are very massive structures that support the cables and also hold them apart. The towers must be very tall so that they can support the cables well above river traffic and clearance must be given for the up and down movement of the deck as vehicles pass over. The towers are usually made of steel or reinforced concrete, but some, like the Golden Gate Bridge, have used suspension chain links in their construction.
The Cables:
The cables are the key to a suspension bridge. They must be very strong in order to support the weight of the Bridge Deck and all the traffic that crosses it. The cables also must be flexible enough to allow for expansion and contraction due to changes in temperature. The main cables of a suspension bridge are composed of many individual wires that are twisted together. These wires are then spun together into larger strands and finally those strands are woven together into the massive cable that we see today.