Queen post

Queen Post

Interior structure of a covered bridge that uses a queen-post structure
Ancestor Truss bridge
Related None
Descendant None
Carries Pedestrians, livestock, vehicles
Span range short to medium
Material wood planks
Movable No
Design effort medium
Falsework required Sometimes

A queen post is a tension member in a truss that can span longer openings than a king post truss. A king post uses one central supporting post, whereas the queen post truss uses two.[1] Even though it is a tension member, rather than a compression member, they are commonly still called a post. A queen post is often confused with a queen strut, one of two compression members in roof framing which do not form a truss in the engineering sense.[2]

Day Bridge in Southwestern Pennsylvania (Morgan Township, Green County)

Architecture

A queen-post bridge has two uprights, placed about one-third of the way from each end of the truss. They are connected across the top by a beam and use a diagonal brace between the outer edges. The central square between the two verticals is either unbraced (on shorter spans), or has one or two diagonal braces for rigidity. A single diagonal reaches between opposite corners; two diagonal braces may either reach from the bottom of each upright post to the center of the upper beam, or form a corner-to-corner "X" inside the square.[3]

See also

References

  1. Gopi, Satheesh. Basic civil engineering. New Delhi: Dorling Kindersley (India) Pvt. Ltd., 2010. 155. Print. ISBN 8131729885
  2. "Timber Framing for Beginners: VI. Glossary of Terms" Timber Framing Vol. 68 June 2003. 12. "Archived copy" (PDF). Archived from the original (PDF) on December 7, 2012. Retrieved December 10, 2012.
  3. American Barns and Covered Bridges, Eric Sloane, Wilfred Funk, Inc. New York, New York; 1954, pg 96-97


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