Types of bridges

Types of bridges
1 - Arch Bridge Arch BridgeArch arch bridge is one of the oldest types of bridges and has a great natural power of resistance which is the transfer of loads, whether living or dead is Zmnha weight of the bridge across the curved arch to the pillars at each end of which is to protect the bow of the stretching and relaxation.

New river bridge

The process of building bridges Alarc need to crafty ideas for example,
Can build a curved arch spans through the cast or fitted by method of construction of the parties to the center by
Supported by the construction of scaffolding underneath even meet in the middle and support themselves.
How does the arch pillars in the process of backing??
Take a ruler length of 30 cm, for example, and fold gently until the arc consists of a curved arch you have, and then clicking on the arc formed you from the midNotice what will happen to the ends of the bow ...!!!

Place the collection of books at each end of the arches. Now what happens? Notice how the piles of books are the pillars, to keep the ends of the bow of the stretching and relaxation.

Then the pillars carry the weight of Alarc and weight of vehicles that pass it to all of this becomes part of the curve Alarc under strong pressure compressionSo it must be the origin of building materials, including materials Alarc strong under strong pressure compression
One of the oldest and most famous example of this type built by the Romans built of stones BC is the channel near the Gard du Bout based î said Mays, France

Bout based in Canal du Gard, FranceToday, the presence of construction materials such as steel and concrete became possible to build longer Alarc spaces and beautiful forms (for example, the new river bridge in the state of West Virginia, a distance of 1700 feet)Usually bridges are Alarc distances between (200-800) feet.

New river bridge
The process of building bridges Alarc need to crafty ideas for example,Can build a curved arch spans through the cast or fitted by method of construction of the parties to the center by their support by building scaffolding underneath even meet in the middle and self-sustaining


Another way is by supporting and lifting cables and by this method is used in cases of establishment Alarc
If one is held above the river was above or through heavy traffic to avoid a disruption to the traffic of one of the innovative new ways in this area which is the way Alkinteliver.

Among the latest bridges Alarc revolutionary design is the impact of the Natchez bridge in Franklin, Tennessee United States, which opened to traffic in 1994, where his determination to adopt concrete prefabricated pre-cast concreteAnd distribute the load on the columns has a side has won numerous awards on how good design and a new idea.

2 - bridge beam (bar or beam) Beam Bridge

Bridge of incidental or beam Hua easier and cheaper types of bridges according to Craig Finlay Finlay / PR down a, "Craig Finley of Finley / McNary Engineering They are considered the reference in the world of bridge."
In the general form is considered a bridge bar is a horizontal beam supported at both ends pillars, which in turn transfer the weight of the beam
(Bridge) to the foundationBeam or the beam itself must be strong and do not bend under the weight and the weight of self-crossing them.When pressed affect or carry down on the beam, the upper edge of the beam and become pressed together under the influence of pressure (compression) and the bottom edge become under the influence of strain (tension).
What happens when the pressure load on a bridge beam (beam)?

Helmets flat piece of eraser or a piece of sponge, and both its small incision in the middle of the top and bottom, then design a bridge beam through the eraser or sponge that will serve as the bar, and located where the collection of books at both ends as if they were pillars of this bridge.Then pressing down in the middle of this bridge.
What happens to divide the top and bottom part ???!!Note the notch in the top How do you get upset how the beam under the influence of pressure, while the bottom part is expanding and spreading out under the influence of tensile strength.
Ideal material used in the construction of a bridge beam is a concrete effort prior Pre-stressed concrete, where concrete is the material has good resistance to the forces of pressure and flooded the iron arms at the bottom is where the steel material has a good denominated in strong tension. The concrete prior effort of the few substances, low-cost building materials in general.But even the best materials can not give away more in length specified in the length.Bridges that are far from the risers are weaker than others as a result.Beam bridges (beam) is rarely up to a maximum of 250 feet that does not mean they do not use to cross long distances, only several bridges must be tied together with what is known as a string in the language of engineering to "continuous span." The extent of continuing.
In fact, the longest bridge in the world Hoa Bridge with radial extent of continuous continuous span beam bridge
A length of 24 miles almost cut Lake Ponchartrain Causeway consists in the state of Louisiana.

It consists of two roads parallel construction completed in 1956 and consists of 2243 Hua bridge connected
The sense that it consists of a series of 2243 Mtslat beam bridge with some.

Suspension bridge (Suspension Bridge)

Golden Gate Bridge in San Francisco of the most famous suspension bridges.

We can summarize our description of the bridges outstanding when viewed them, light weight, beautiful, powerful, outstanding Vakabari can reach distances of 2,000 to 7,000 feet - a much longer than any other type of bridge. It is also the most expensive in terms of cost and construction of any kind from the other bridges. The suspension bridge of his name reflects the described where most of the road hanging cables Home (main cables) where stretches main cables from the beginning of the bridge to an end, the main cables to be extended over the towers, columns, bridge and be tight at both ends of the bridge by the basis of the installation or anchors ( anchorages).
The basis of installed cables (anchorages)

Picture of the process of establishing the foundations of the installation Anchorage construction

Picture of the process of lifting cables when the foundations of the installation

And enables the towers, columns, suspension bridge main cables that wraps and extends to long distances
Where most of the weight of the bridge carrying cables to anchors or the basis of the installation (anchorages)Prove that any main cables, either in solid rock or massive concrete blocks.
Within the foundations of the installation, spread over a large area cables to distribute the load evenly and to prevent the cablesEmancipation of the interruption.

What is the idea of ​​the foundations of the installation anchors (anchorages)?

First: Connect two nodes of the rope around the upper Glavi two books with the same size hard disks and then tie a rope between the last Alakaditn even hanging on loosely between the books, and then click on the middle third of the rope to see what happens?

Second: Place the two books and standing about 10 inches, and then put a pile booklet heavy on the edge of the two books standing and then brought the rope and install it than when you stack the books then passed the rope over the books standing to the other side and then place the stack other books on the other side, and bibliographic the rope is also in this side and you can leave the cord hanging some thing that does not have any tight or completely. Click again on the center of the string. See what happens? Note also how the piles of books, the process of installing the bridge, where piles of books here as the foundations of the installation (anchorages).

A bundle or group of cables Akashi Bridge Home

The Bridge Humber Humber bridge in England is the longest bridge distance carried on cable, where the distance is 4.623 feet, but now the world record of the share of the bridge Japan with a cost of 706 billion dollars Bridge Akashi Keiko Akashi Kaikyo Bridge, which opened in 1998, and connecting the islands of Honshu, and Shikoku Honshu and Shikoku and the average distance of up to a portable 6.527 feet.
Humber Bridge Humber bridge


To keep the bridges outstanding stable as it basically is a lightweight and flexible engineers to add areas like Balbndol on the towers to keep them from swinging and also converged to add the so-called Balzanfah stable at the center of origin such as is found under the ship to resist the power of wind, especially wind storms so that the strong wind is one of the most dangerous forces that affect the origin, but this is outstanding and the bridges that led to the collapse of the Tacoma Washington Bridge because of strong winds after its opening four monthsWhere he opened the bridge Strait Tacoma Washington in 1940 and was then the longest third bridge hangs in the world, with the title at the time of the local population including means running quickly on a horse "Galloping Gertie," the proportion to his behavior with the wind where it was not swaying side only, but it undulates vertically This was also observed bobbing with little wind and relatively calm. The spikes to make motorists who pass by the bridge to report these ripples and Staggers where they Abulgo the cars that ran the bridge disappear and show the impact of the ripples that you get to the bridge and there have been several attempts to install the bridge by stabilizers Hedrolekih and a set of cables, but those attempts failed. the abysmalIn the seventh month of November 1940 four months after the opening of the bridge, the Strait of Tacoma Washington bridge collapsed due to wind speeds of 42 miles / hour with because he was determined to bear the strength of winds faster than 120 miles / hour.
Pictures of bridge to shake the Strait of Tacoma and Tmaalh and then collapse


This failure caused the collapse and a great shock to the engineering community and has become a questionHow is the provenance of a length greater than half a mile and weighs tens of thousands of tonsThe collapse because of relatively light winds and the movement of a relatively simple and the affect itThis strong influence to make it fall apartIn order to find engineers to answer this question disease the application of science aerodynamics aerodynamics in the design of bridges and experts continue to Altgueniyon disagree on the cause of the collapse of this bridge, but most agree that the phenomenon is similar to the phenomenon of resonance is the cause of this apparent e are similar to the phenomenon that occurs the voice of God of music lead to shattered glassNow, the wind tunnel testing is very important and mandatory in the design of bridges and became aware of the basics of design of bridges.
For the bridge, the Strait of Tacoma, Washington was Alibd in the re-built in 1949 and became the new bridge show and also was supported under along the way Bgamalon trusses and hollow cylinders in the middle of all that has been added to the design to resist the strong wind has deep stiffening trusses under the roadway and even sports a slender gap down the middle


Backed bridge or cable provider (Cable-Stayed Bridge)

Supported bridges may seem like cables for bridges outstanding way in which
Laptop cables and both have towers, but the way of support and distribution of loads
Of the road is quite differentThe difference is in the way the cable connection with towers towers in the pending cable extends freely through the power of the towers tanker loads to anchors anchorage at the ends of the bridge The bridges supported by cables installed in the towers that take the load alone.
* You can install the cable on the road in several configurations, including a model of radiation half a country where the cables extend from several points on the road to a single point at the top of the tower

And also a form of radiation, where the parallel cable show in different heights along the tower to extend parallel to each

How does the cable support?Stand with your arms extended horizontally on each side of the bridge are imagining your arms and your head is the tower in the middle of this situation, your muscles are supported by your armsTried to make the idea of ​​supporting cables to support your arms, take a piece of rope five feet long and let your colleague that joins both ends of the rope to each of your elbows, and then put the center of the rope over your head, rope work here and guest support to carry the cables and elbowsMark your colleague a link length of a second piece of rope about 6 feet to each wrist put the rope over your headYou now have cables to support your arms at your elbows and wrists.Where now feels strongly pressure?Notice how the cables that support the movement force of the bridge (your arms) to the tower (your head) the outcome of any transfer of power from the bridge to the tower ..Stand and Hold your weapons abroad horizontally on each side. Imagine that your arms bridge, and head tower in the middle. In this mode, your muscles are supported by your arms.

Although the bridges supported by cables innovative idea but the idea is not new, where he found a sketch of this idea in a book called Machinae Novae in the publication in 1595 AD But the engineers did Abdo in the use of this idea, but in our centuryWas initially using this idea after World War II in Europe in the rebuilding of destroyed bridges, especially bridges that did not take long destruction of their foundations. (Bases), where the steel was rarely on time.

Began in the United States supported the establishment of cables newly bridges where there was a revolutionary event and met with great admiration.
Diagram of a provider bridge cables in Sydney
Average length free medium length spans of this type of bridges between 500 to 2800 feet.

Higher bridge linking Sweden and Denmark is the longest bridge in the world for this type

The bridges are supported by cables to the first choice of engineers and bridges compared to the outstanding Valjsur supported cables consume less than the amount of cables and can be built identical parts of Precast Concrete identical pre-cast concrete sections and faster construction.The result is we have a bridge in the economic cost Odhu unrivaled aesthetic form.

Sunshine Skyway Bridge

Horizontal scroll: Greetings: Anas Ramadan student at the Higher Institute of Technology, Benha Moved from Eng freestar in 1988 won the Bridge Sunshine Skyway in Tampa, Florida Design Award Presidential National Endowment for the Arts, where painted yellow to be compatible with the environment marine in his area, one of the bridges, the first proven Kwablh in the mid-way on the reverse is common in the design of this type of bridges, which are often installed on the limbs Kwablh Although common options that cost less but city officials adopted a method of installing cable in the middle so you can enjoy a view of the Gulf and the natural beauty of the area.

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