Bridges_notes

 **Some questions to reflect about:** 1. Are all bridges alike? Bridges can be different from each other in the morphological sense, they can have different materials and different designs, however the purpose of a bridge and its basic structure will remain constant. Think of the bridges you remember: Wood, iron, steel, rock...  Examples: Wooden bridge over Enipeas River Stone Bridge River Duje
 * What are they made of?

They connect two places or points, usually divided or separated by an obstacle of some sort.  It varies a lot, in some occasions the span is shorter or larger, and the bridge can have several elements all the way through one pier or tower to another, like arcs or strings. 2. What social and/or political benefits can bridges provide to places? They shorten distances from one place to another so people can arrive sooner and in that way the country progresses because it makes an advance in the routes of transportation. I think originally they were build in order for people to communicate and interact with other places.
 * What are they connecting?
 * How is the span between their piers or towers?
 * Why were the bridges built?
 * Did they provide benefits? To whom? Why?

Yes, given that they connect two points in an efficient way it can help in several aspects: They connect us socially, increase and helps the routes commercially etc.

Notes on Bridges - Bridges are technological tools that aim to solve the problem of crossing an obstacle in such a way as to cut down the effort and time needed to do so. - They have many benefits, for instance supplies and other things can get from one place to another in a shorter time. They also help people to travel in an easier and safer way so that they can share ideas, intellectual, political etc enriching society itself. - <span style="font-family: Arial,sans-serif; font-size: 10pt;">Artists, architects and engineers pour vast resources into bridge construction and, in doing so, reshape the very environment in which we live. <span style="font-family: Arial,sans-serif; font-size: 10pt;">- There are ancient bridges such as:

<span style="font-family: Arial,sans-serif; font-size: 10pt;"> & <span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;"> Arkadiko Bridge iGreece Meghalaya Living Bridges (India)

<span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">- The key structural components of bridge construction are: **<span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">beams **<span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">, **<span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">arches **<span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">, **<span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">trusses **<span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;"> and **<span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">suspensions (BATS) **<span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">. Various combinations of these four technologies allow for numerous bridge designs. <span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">- Compression and tension are present in all bridges and they are both capable of damaging part of the bridge as varying load weights and other forces act on the structure. It's the job of the bridge design to handle these forces without buckling or snapping. The best way to deal with these powerful forces is to either dissipate them or transfer them. <span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">- Many beam bridges use concrete or steel beams to handle the load. The size of the beam, and in particular the height of the beam, controls the distance that the beam can span. By increasing the height of the beam, the beam has more material to dissipate the tension.

=__**<span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">Types of Bridges **__=


 * **__<span style="font-family: arial,helvetica,clean,sans-serif;">Arch Bridge: __** <span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;"><span style="background-color: #ffffff; color: #333333; font-family: arial,helvetica,clean,sans-serif;">Its semicircular structure elegantly distributes compression through its entire form and diverts weight onto its two abutments, the components of the bridge that directly take on pressure. <span style="font-family: Arial,sans-serif; font-size: 10pt;">The essence of an arch is that ideally there should be no tendency for it to bend, except under live loads. It should be purely in compression, and for that reason it can be made of materials such as, masonry, cast iron and concrete, that perform poorly in tension.

<span style="font-family: Arial,sans-serif;">Examples:



<span style="font-family: Arial,sans-serif; font-size: 10pt;"> Yesanhe River A <span style="font-family: Arial,sans-serif; font-size: 10pt;">rch Bridge (China) New River Gorge Bridge in West Virginia

<span style="font-family: Arial,sans-serif;"> <span style="font-family: Arial,sans-serif;">Examples: <span style="font-family: Arial,sans-serif; font-size: 10pt;"> Texcapa Bridge (Mexico) <span style="font-family: Arial,sans-serif;"> <span style="font-family: Arial,sans-serif;"> <span style="font-family: Arial,sans-serif;">Examples:
 * **__<span style="font-family: arial,helvetica,clean,sans-serif;">Beam Bridge: __** <span style="font-family: Arial,sans-serif; font-size: 10pt;">Conformed basically by a rigid horizontal structure (a beam) and two, or more supports, one at each end, to rest it on. These components directly support the downward weight of the bridge and any traffic traveling over it.
 * ** ** ** ** __<span style="font-family: arial,helvetica,clean,sans-serif;">Cable-Stayed Bridge: __ ** ** ** **<span style="font-family: Arial,sans-serif; font-size: 10pt;">It’s a bridge that consists of one or more columns, with cables supporting the bridge deck. Cable-stayed bridges don't require anchorages, instead, the cables run from the roadway up to a single tower that alone bears the weight. The cables attach to the roadway in various ways.





<span style="font-family: Arial,sans-serif; font-size: 10pt;"> Memorial Bridge, Boston, USA

<span style="font-family: Arial,sans-serif;">
 * **__<span style="font-family: arial,helvetica,clean,sans-serif;">Cantilever Bridge: __** <span style="font-family: Arial,sans-serif; font-size: 10pt;">A cantilever bridge is a bridge built using beams that project horizontally into space and that are anchored at one end only.

<span style="font-family: Arial,sans-serif;"> <span style="font-family: Arial,sans-serif;">
 * **__<span style="font-family: arial,helvetica,clean,sans-serif;">Suspension Bridge: __** <span style="font-family: Arial,sans-serif; font-size: 10pt;">Suspension bridge, suspend the roadway by cables, ropes or chains from two tall towers.The towers then dissipate the compression directly into the earth.

<span style="font-family: Arial,sans-serif;">Examples: <span style="font-family: Arial,sans-serif;"> <span style="font-family: arial,helvetica,clean,sans-serif;"> <span style="font-family: arial,helvetica,clean,sans-serif;"> **Brooklyn Bridge, USA** <span style="font-family: Arial,sans-serif; font-size: 10pt;">Clifton Suspension Bridge, UK  <span style="font-family: arial,helvetica,clean,sans-serif;"> <span style="font-family: Arial,sans-serif;"> <span style="font-family: Arial,sans-serif;"> <span style="font-family: Arial,sans-serif; font-size: 10pt;">The Socastee Intracoastal Waterway Swing Bridge, US
 * ** ** __**__<span style="font-family: arial,helvetica,clean,sans-serif;">Truss Bridge: __**__ ** **<span style="font-family: Arial,sans-serif; font-size: 10pt;">A truss bridge is a bridge composed of connected elements. They are usually made of steel beams, creating a structure of triangles. They are a variation of the beam bridge type.