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Saturday, January 30

  1. page Influences edited How did technology influence bridge building ? by making the process of building a bridge easie…

    How did technology influence bridge building ?
    by making the process of building a bridge easier and faster,
    and with technology they have more tools and machines to help them.
    How did building bridges influence the bahraini culture ?
    by making it easier to go place to place without traffic,
    also now with bridges we can have roads over rivers, lakes.

    (view changes)
    12:40 am
  2. page Strengths and Weaknesses edited Strengths and Weaknesses - Arch bridge : Arch bridges are one of the oldest types of bridges and…
    Strengths and Weaknesses -
    Arch bridge : Arch bridges are one of the oldest types of bridges and have great natural strength. Instead of pushing straight down, the weight of an arch bridge is carried outward along the curve of the arch to the supports at each end. These supports, called the abutments, carry the load and keep the ends of the bridge from spreading out.
    Beam bridge : A beam or "girder" bridge is the simplest and most inexpensive kind of bridge. In its most basic form, a beam bridge consists of a horizontal beam that is supported at each end by piers. The weight of the beam pushes straight down on the piers.
    The beam itself must be strong so that it doesn't bend under its own weight and the added weight of crossing traffic. When a load pushes down on the beam, the beam's top edge is pushed together while the bottom edge is stretched (tension).
    Truss bridge : Truss bridges may look similar to suspensions bridges—both have roadways that hang from cables and both have towers. But the two bridges support the load of the roadway in very different ways. The difference lies in how the cables are connected to the towers. In suspension bridges, the cables ride freely across the towers, transmitting the load to the anchorages at either end. In cable-stayed bridges, the cables are attached to the towers, which alone bear the load.
    Suspension bridge : Suspension bridges can span distances from 2,000 to 7,000 feet—far longer than any other kind of bridge. They also tend to be the most expensive to build. True to its name, a suspension bridge suspends the roadway from huge main cables, which extend from one end of the bridge to the other. These cables rest on top of high towers and are secured at each end by anchorages. The towers enable the main cables to be draped over long distances.
    Most of the weight of the bridge is carried by the cables to the anchorages, which are imbedded in either solid rock or massive concrete blocks. Inside the anchorages, the cables are spread over a large area to evenly distribute the load and to prevent the cables from breaking free.

    (view changes)
    12:31 am
  3. page Features and Forces edited ... Tension and compression are the two main forces. Tension is pulling. It would be hard to break…
    ...
    Tension and compression are the two main forces. Tension is pulling. It would be hard to break a straw if you held both ends and pulled apart. Wood also has the ability to resist tension. Tension may be applied parallel to the grain of the wood, but should be avoided perpendicular to the grain. Wood is very strong in tension parallel to the grain, but extremely weak in tension perpendicular to the grain.
    Compression is a pushing (compressing) force. The shorter a piece of wood is, the more compression it can hold. The longer a piece of wood is, the less compression it can hold.
    Strengths and Weaknesses -
    Arch bridge : Arch bridges are one of the oldest types of bridges and have great natural strength. Instead of pushing straight down, the weight of an arch bridge is carried outward along the curve of the arch to the supports at each end. These supports, called the abutments, carry the load and keep the ends of the bridge from spreading out.
    Beam bridge :

    (view changes)
    12:24 am
  4. page Features and Forces edited ... The three basic types of spans are shown below. Any of these spans may be constructed using be…
    ...
    The three basic types of spans are shown below. Any of these spans may be constructed using beams, girders or trusses. Arch bridges are either simple or continuous. A cantilever bridge may also include a suspended span.
    Forces on a bridge -
    Tension and contractioncompression are the
    ...
    main forces.
    Strengths
    Tension is pulling. It would be hard to break a straw if you held both ends and pulled apart. Wood also has the ability to resist tension. Tension may be applied parallel to the grain of the wood, but should be avoided perpendicular to the grain. Wood is very strong in tension parallel to the grain, but extremely weak in tension perpendicular to the grain.
    Compression is a pushing (compressing) force. The shorter a piece of wood is, the more compression it can hold. The longer a piece of wood is, the less compression it can hold.
    Strengths
    and Weaknesses -
    Arch bridge : Arch bridges are one of the oldest types of bridges and have great natural strength. Instead of pushing straight down, the weight of an arch bridge is carried outward along the curve of the arch to the supports at each end. These supports, called the abutments, carry the load and keep the ends of the bridge from spreading out.
    Beam bridge :

    (view changes)
    12:23 am
  5. page Features and Forces edited Some features Features - The four main factors are used in describing a bridge. By combining t…
    Some featuresFeatures -
    The four main factors are used in describing a bridge. By combining these terms one may give a general description of most bridge types.
    span,
    ...
    form
    The three basic types of spans are shown below. Any of these spans may be constructed using beams, girders or trusses. Arch bridges are either simple or continuous. A cantilever bridge may also include a suspended span.
    ...
    bridge -
    Tension and contraction are the two main forces.
    Strengths and weaknessesWeaknesses -
    (view changes)
    12:14 am

Thursday, January 28

  1. page Features and Forces edited ... form The three basic types of spans are shown below. Any of these spans may be constructed us…
    ...
    form
    The three basic types of spans are shown below. Any of these spans may be constructed using beams, girders or trusses. Arch bridges are either simple or continuous. A cantilever bridge may also include a suspended span.
    Advantages & DisadvantagesForces on a bridge -
    Tension and contraction are the two main forces.
    Strengths and weaknesses
    -
    (view changes)
    11:24 pm
  2. page Glossary edited Words you need to know to get started; Compression : is the reduction in size of data in order to…
    Words you need to know to get started;
    Compression : is the reduction in size of data in order to save space or transmission time.
    Deck : any of various platforms built into a vessel.
    Engineer : work to develop economical and safe solution to practical problems.
    Girder : is a support beam used in construction.
    Load : forces which are applied to structure.
    Span : the distance or interval between two points.
    Tension : is a force that acts to expand or lengthens the thing its acting on.
    Torsion : is a matter of characterizing a twist or screw of a moving frame around a curve.
    Truss : is a bridge composed of connected elements, which may be stressed from tension, compression, or sometimes both in response to dynamic loads.

    (view changes)
    11:19 pm
  3. page Truss Bridges edited ... {250px-Quebec_Bridge_-_Pont_de_Québec.jpg} Cantilever & Truss Bridge. MATERIALS: stee…
    ...
    {250px-Quebec_Bridge_-_Pont_de_Québec.jpg}
    Cantilever & Truss Bridge.
    MATERIALS:
    steel rope,
    multiple steel wire,
    stand cables.

    (view changes)
    11:05 pm
  4. page Cantilever Bridges edited ... Cantilever bridges are built using cantilevers—horizontal beams that are supported on only one…
    ...
    Cantilever bridges are built using cantilevers—horizontal beams that are supported on only one end. Most cantilever bridges use two cantilever arms extending from opposite sides of the obstacle to be crossed, meeting at the center. The largest cantilever bridge is the 549-metre (1,800 ft) Quebec Bridge in Quebec, Canada.
    {250px-Quebec_Bridge_-_Pont_de_Québec.jpg} The Quebec bridge from the east side, with the Pierre-Laporte bridge in the background.
    MATERIALS:
    iron,
    structural steel,
    prestressed and reinforced concrete.

    (view changes)
    11:01 pm

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