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Bollman, Wendel

Walnut Street Bridge
Society: ASCEMain Category: CivilSub Category: BridgesEra: 1890-1899DateCreated: 1890Susquehanna RiverHarrisburdState: PAZip: 17101Country: USAWebsite: http://www.asce.org/Project/Walnut-Street-Bridge/Creator: Bollman, Wendel , Reeves, Samuel

The structure has two segments: an East Channel bridge consisting of four 175-foot spans and three 240-foot spans crossing from Harrisburg to City Island; and a West Channel bridge, consisting of seven 175-foot spans crossing from City Island to Wormleysburg.

With 15 truss spans totaling 2,820 feet, the Walnut Street Bridge is the finest and largest surviving example of the standardized Phoenix wrought-iron truss bridges produced from 1884 to 1923.

YearAdded:
1997
Image Credit: Courtesy Flickr/rjonesProject856 (cc-by-2.0)Image Caption: Walnut Street BridgeEra_date_from: 1890
Bollman Truss Bridge
Society: ASCEMain Category: CivilSub Category: Bridges, TransportationEra: 1860-1869DateCreated: 1869Little Patuxent RiverSavageState: MDCountry: USAWebsite: http://www.asce.org/Project/Bollman-Truss-Bridge/Creator: Bollman, Wendel

The design of the Bollman Truss Bridge-patented in 1852 and one of the first to use iron exclusively in all essential structural elements-was critical in the rapid expansion of American railroads in the 19th century. Replacing wooden bridges, which  were cumbersome to build and vulnerable to decay, the Bollman Truss Bridge could be built relatively quickly and inexpensively, while providing the long-lasting qualities associated with metal. This allowed new rail lines to be built over long distances in a short period of time.

YearAdded:
1966
Image Credit: Courtesy Flickr/Andrew Bossi (CC BY-SA 2.0)Image Caption: Bollman Truss Bridge as it looks today, after the repairs done in 1934-84.Era_date_from: 1869
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Bollman Truss Bridge

The design of the Bollman Truss Bridge-patented in 1852 and one of the first to use iron exclusively in all essential structural elements-was critical in the rapid expansion of American railroads in the 19th century. Replacing wooden bridges, which  were cumbersome to build and vulnerable to…

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Walnut Street Bridge

The structure has two segments: an East Channel bridge consisting of four 175-foot spans and three 240-foot spans crossing from Harrisburg to City Island; and a West Channel bridge, consisting of seven 175-foot spans crossing from City Island to Wormleysburg.

With 15 truss spans totaling…

Read More

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