Photos
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Oblique view Photos taken Dec. 2006 by Ruth Reynolds |
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Deck view |
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Barricade fence |
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Plaque |
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1905 Photo taken by Robert Elder in February 2004 |
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This photo shows how the main span of this bridge is a "Reverse Parker". Photo taken by Robert Elder in 2002 |
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Photo taken by Robert Elder in 2002 |
An Unusual Truss Design
Written by Robert ElderThere have been some interesting discussions on this page concerning the design of the Asylum Bridge. The bridge generally appears to be of a Cantilevered design, but also features a Parker truss, with inverted top chords as the main span. This main span is comprised of eight panels. The two middle panels contain counters in addition to the diagonal members. The inverted top chords seem to be the only features that distinguish the main span (ignoring the "towers") of the Asylum Bridge from a standard Parker truss.
A standard Cantilever truss would generally feature alternating diagonal members, often of heavy or "built up" steel. These alternating diagonal members can be seen very well on the Murray Baker Bridge in Illinois. http://www.bridgehunter.com/il/peoria/illinois-74/ and on the much smaller Neosho River Bridge in Lyon County, Kansas http://www.bridgehunter.com/ks/lyon/560350/ Similar alternating diagonal members are not found on the Asylum Bridge, which was buit in 1905, well before the Cantilever truss became a popular design.
Thus, the Asylum Bridge is neither a Parker truss, nor a standard Cantilever span. The suspension of a separate truss within a Cantilever truss is unusual, but can also be seen on the Lansing Bridge in Iowa/Wisconsin, which contains a Pennsylvania truss that is supported by the main cantilever structure. http://www.bridgehunter.com/ia/allamakee/black-hawk/ Notice that the suspended span on the Lansing bridge is not connected directly to the substructure.
Unlike the Lansing Bridge, the main span of the Asylum Bridge (the "Reverse Parker" span) is supported directly by the same stone piers that support the "towers" which give the bridge a Cantilever appearance.
I have been able to locate some further information concerning this bridge. The Kansas State Historical Society completed a National Register nomination for for the Asylum Bridge. That form is now online and can be viewed either as a PDF
http://www.kshs.org/resource/national_register/nominationsNRDB/Miami_AsylumBridgeNR.pdf or as an HTML document http://74.125.47.132/search?q=cache:8SFM3rbVVN4J:www.kshs.org/resource/national_register/nominationsNRDB/Miami_AsylumBridgeNR.pdf+asylum+bridge&cd=15&hl=en&ct=clnk&gl=us
Although the above forms refer to the Asylum Bridge as being a single span, it could be considered to be comprised of three spans. These would include the main span and the two approach spans which rest on the aforementioned stone piers. All three of these spans appear to be suspended by the "towers".
Regardless of how one would classify the Asylum Bridge, it remains as one of the most unique truss bridges in the United States.
Facts
- Overview
- Reverse Parker through truss bridge over Marais Des Cygnes River on 1st Street in Osawatomie
- Location
- Osawatomie, Miami County, Kansas
- Status
- Closed to all traffic
- History
- Built 1905 by the Kansas City Bridge Co.
- Builder
- - Kansas City Bridge Co. of Kansas City, Missouri
- Design
- Reverse Parker through truss
- Dimensions
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Length of largest span: 121.0 ft.
Total length: 219.1 ft.
Deck width: 16.0 ft.
Vertical clearance above deck: 15.5 ft.
- Recognition
- Posted to the National Register of Historic Places
- Approximate latitude, longitude
- +38.50506, -94.95372 (decimal degrees)
38°30'18" N, 94°57'13" W (degrees°minutes'seconds") - Approximate UTM coordinates
- 15/329644/4263663 (zone/easting/northing)
- USGS topographic map
- Paola West
- Inventory numbers
- NRHP 89002187 (National Register of Historic Places reference number)
BH 18104 (Bridgehunter.com ID) - Inspection (as of 08/2007)
- Substructure condition rating: Poor (4 out of 9)
Appraisal: Structurally deficient
Sufficiency rating: 19.5 (out of 100)
Update Log
- June 14, 2009: Essay added by Robert Elder
- July 9, 2008: New photo from Robert Elder
- February 27, 2008: Updated by Robert Elder: Changed "Overview" and "Design" from "Through truss" to "Reverse Parker through truss".
- February 18, 2008: New photo from Robert Elder
- January 11, 2007: Posted photos from Ruth Reynolds
Comments
I am not certain when the technology for this style originated initially. This particular bridge was built in 1905 however. I agree, it is a very interesting, and rare style of bridge. Thankfully it has been listed on the National Register of Historic Places. I would like to see it restored however. Most of the bridge, including much of the truss was submerged in a major flood in 2007. Thankfully, it survived.
The Plaque looks like it says "1805", rather than 1905. Is that possible? Did they even have this technology in 1805?
I would vote this bridge the one of the most interesting bridges on this web site. Definitely in the top 5. I sure hope somebody jumps on this beautiful example and preserves it.
It's funny you mention this, because on more than one occasion my wife has threatened to have me committed. I have a unique ability to turn just about any trip into a bridge hunt.......drives her crazy! HUH
LOL J.R Manning. I guess with our hobby, any bridge could be the Asylum Bridge. The State of Kansas has a mental health facility near the north end of the bridge. When the bridge was open, it could be used to access the site.
I love this, if for no other reason than all the names for the bridge, the location and the waterway! Anyone know why it's called the Asylum Bridge? (Besides the fact that most of us bridge hunters are headed there?)
The center span of this bridge is actually a Parker Truss with the top chords inverted so they "dip" towards the center of the span, hence the term Reverse Parker. This is easier seen in a side view of the bridge. This bridge is believed to be the only Reverse Parker Truss in existence.
Looks like a small cantilever bridge to me, ie a continuous through truss. Stylistically similar to the Thamesville Bridge in Ontario. I am not familiar with the term "reverse parker" unless this was an early term to describe cantilever technology.
This is a Reverse Parker through truss. This may possibly be the only example of Reverse Parker in existance.