Editing Bridge (section)

===Fixed or movable bridges===
{{Redirect|Fixed link|other uses|Intercontinental and transoceanic fixed links|and|Link (disambiguation)}}
[[File:AVLB 01.jpg|thumb|Alvis Unipower TBT (tank bridge transporter) of the British army]]
Most bridges are fixed bridges, meaning they have no moving parts and stay in one place until they fail or are demolished. Temporary bridges, such as [[Bailey bridge]]s, are designed to be assembled, taken apart, transported to a different site, and re-used. They are important in military engineering and are also used to carry traffic while an old bridge is being rebuilt. [[Movable bridge]]s are designed to move out of the way of boats or other kinds of traffic, which would otherwise be too tall to fit. These are generally electrically powered.<ref>{{Cite book|last=Hovey|first=Otis Ellis|title=Movable bridges|publisher=John Wiley & Sons, Inc.|year=1927|location=New York|pages=1–2|hdl=2027/mdp.39015068174518}}</ref>

The tank bridge transporter (TBT) has the same cross-country performance as a tank even when fully loaded. It can deploy, drop off and load bridges independently, but it cannot recover them.<ref>{{cite web |url=http://army.mod.uk/royalengineers/equipment/702.aspx |title=Close Support Bridging (CSB) - British Army Website |publisher=Army.mod.uk |accessdate=2012-08-07 |archive-url=https://web.archive.org/web/20111126032356/http://army.mod.uk/royalengineers/equipment/702.aspx |archive-date=2011-11-26 |url-status=live }}</ref>