Arch Bridge Definition
A arch bridge is a type of suspension bridge which consists of two or more arches connected by beams. The arched structure provides stability to the weight of vehicles or other objects placed on top of it. Arch bridges are usually made from wood, but steel and concrete have been used as well. They can span great distances with little effort and they can support loads up to several tons without any problems.
Some arch bridges are even capable of supporting human beings at times!
Arch bridges were originally designed to allow ships to travel across oceans without having to navigate dangerous shoals. Today, arch bridges are often used for transportation purposes such as trains, buses and trucks. They are also commonly found in cities where they provide access between different areas.
Arch Bridges Materials
The most common material used for arch bridges is wooden beams. However, steel and concrete have also been used. Steel arch bridges are generally stronger than their wooden counterparts due to its greater strength per unit weight ratio. Concrete arch bridges tend to be lighter than their timber counterparts because they don’t require as much reinforcement.
Most modern arch bridge structures use aluminum or stainless steel as the main structural element instead of wood.
Types Of Arch Bridges
There are various types of arch bridges. Here are some examples:
Tied Arch Bridge – A Tied Arch Bridge is one in which the arch supports the load of a vehicle or object placed on top of it. When a car or truck is put on top of an arch bridge, it will not fall down because there is a solid support underneath. A tied arch bridge is usually the cheapest type of arch bridge because it can be made from readily available materials such as wood.
Suspension Bridge – A suspended bridge is supported by cables which are connected to two or more towers. The weight of the vehicle or load pushes down on the bridge, which in turn, puts pressure on the cables. The cables that support the load are anchored by the towers on either side of the river or valley. A pin connects the cables to the bridge deck, which is a platform or series of decks that vehicles or objects travel on.
A suspended bridge can span great distances without needing vertical supports in the middle.
Suspension bridges are usually made from metal and these days, steel is the most common material because it is strong and durable. However, early suspension bridges were made from wood because it was widely available at the time. The problem with wooden bridges is that they require regular maintenance or they can even collapse.
Beam Bridge – A beam bridge consists of a series of parallel beams laid across a river. The purpose of the bridge is to get people or vehicles from one side to the other. A beam bridge is constructed by laying beams across the river and then either anchoring them on both sides or using cables attached to each end of the beams on both sides as well. The ends of the beams can either touch the bottom of the river or rest on supports such as piers.
The oldest beam bridges were made out of wood and haven’t survived the ravages of time. Some of the oldest stone beam bridges that still exist are Roman in origin and were constructed using mortar and stone blocks.
Post Bridge – A post bridge is an interesting structure in that it doesn’t span the entire river. Instead, there are posts or pillars on both sides of the river. This allows people or vehicles to cross the river without interfering with boat traffic which might be going up and down stream. A post bridge can either have a deck that allows people to walk on it or it can just be for vehicle traffic.
The type of bridge that you have depends largely on the amount of traffic that needs to cross the river.
A post bridge can be made of wood, stone or a combination of both. The original bridges made by settlers in the 1800s were usually just made out of logs that were laid across the river. These types of bridges are dangerous because they often sink into the soft soil near the river and people have been known to fall through cracks onto rocks below.
One of the most famous post bridges in American history is the covered wagon bridge that Lewis and Clark used to cross the Missouri River. It was made out of pine logs that were laid side by side across the Missouri River and had a tall, square cabin on each end. It saved the lives of the entire Corps of Discovery when they were crossing the river during a sand storm and allowed them to ride out the storm in relative safety.
Another bridge that was made during the Lewis and Clark expedition was a raft they used to cross the Clearwater River in Idaho. The raft was 13-feet square and had the words “U.S. Army” painted on each side.
It also had oars and a rudder made out of a wooden wash tub. The name for the river was given by William Clark during the expedition and is unusual in that it has been the only river in the United States to have an apostrophe in its name.
The city of Lewiston, Idaho sits where the Snake River meets the Clearwater River and is known for being one of the main centers for processing phosphate. Not far away is Clarkston, Washington where the Nez Perce Indian Reservation is located and the final battle of the Nez Perce War took place in 1877.
Bridge Facts and Trivia
There are more than 2 million bridges in the world.
The earliest known bridge in the world is the Ding-Zhuang Bridge in China and was made of wood and ropes and was used for foot traffic only.
The longest bridge in the world is the Donghai Bridge which was opened in 2005 and stretches almost 52 miles across the Shanghai sea.
A. The next bridge after that is the Verrazzano-Narrows Bridge in New York City which spans 8,981 feet over the Hudson River.
B. The next bridge after that is the Tsing Ma Bridge which also spans over the water and connects Hong Kong, China to the New Territories area of Kowloon.
A. The next bridge is the Akashi Kaikyō Bridge which is located in Japan and spans almost 6,532 feet over the Tokai Strait to connect the city of Kobe on the mainland of Honshu to Iwaya Peninsula on Awaji Island.
B. The next bridge after that is the Humber Bridge in the city of Kingston-Upon-Hull, England.
A. The next bridge is the second bridge in New York City and is called the Verrazano-Narrows Bridge. It connects Staten Island in New York City to Brooklyn.
B. The next bridge is the Tsing Ma Bridge which connects Kowloon, Hong Kong to the New Territories area of Hong Kong over the water.
C. The next bridge after that is the Akashi-Kaikyō Bridge which connects the city of Kobe on the mainland of Honshu to Iwaya Peninsula on Awaji Island over the water as well.
D. The last bridge is the Humber Bridge in the city of Kingston-Upon-Hull, England.
E. Thousands of people die every year from leaning too far over a bridge railing or falling while taking a picture and falling off a bridge.
F. The Golden Gate Bridge has been featured in several movies most notably “Vertical Limit” and “Jump Off Louisiana.”
G. The city of Ryugyong in North Korea is a modernist nightmare that has 133 story skyscraper that has remained unoccupied since it was built.
H. Before the Eiffel Tower was built, an engineer suggested that a 3,000-foot tall statue of an angel be built instead of a monument.
I. The world’s first parking meter was installed in Oklahoma City in July, 1935.
J. In the 1800s, a Philadelphia inventor created a carriage that ran on steam power and had a boiler inside it to produce the steam. The ride could reach speeds of up to 35 mph.
K. There is a town in Minnesota called Santa Claus which features a life-size metal Santa Claus statue surrounded by Christmas trees and displays at the town park, church and even the town bar.
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