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Key Facts |
Bridge Name | Type | Road | Location | City | Crossing |
| Perry Highway Bridge | Truss | US-19 (Perry Highway) | Mercer County, PA | Rural | Neshannock Creek |
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Technical Facts |
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Construction Date |
Rehabilitation Date |
Structure Length | Deck Width | Builder |
| 1928 | 1975 | 133 Feet | 24 Feet | Unknown |
My photos of this bridge are abysmal, thanks to weather in Pennsylvania that seems to turn to rain whenever I enter the state! This was a bad situation, with dark clouds over the bridge making it dark, and lighter skies in the distance, washing out my photos. If I had to pick one bridge to have the bad weather at, I would pick this one though, as compared to the other Mercer County metal truss bridges, this is the least pleasing in my mind. On the other hand, I am not saying that preserving this bridge is pointless. On the contrary, this is still a beautiful structure. But if I had to pick favorites, this would not be at the top. The historic bridge inventory often lists truss bridges as non-historic because of some little modification like replacing some rivets with bolts, or replacing a diagonal member, etc. I think that is silly, because such small modifications do not affect the overall historic appearance of the bridge. The modification done to this bridge however is blatant and hard not to notice. Galvanized steel bracing was added of all places to the outside of the bridge, supposedly to increase the room inside the trusses. The knee bracing inside the bridge was then removed. It is rather strange looking. On the other hand, if these modifications have kept the bridge able to carry traffic, and have saved it from demolition, then I guess it is worth it.
Information and Findings From Pennsylvania's Historic Bridge InventoryDiscussion of Bridge The 1928, riveted, single span, 133'-long, Pratt thru truss bridge is supported on concrete abutments with flared wingwalls. The heavy trusses are composed of built up members. Connections were changed in 1975 from rivets to high strength bolts at some lower panels points and at the battens of the lower chords. The bridge has no innovative or distinctive details. It is a late example of a common technology used in Pennsylvania since ca. 1890 and built with frequency by both county and state highway bridge builders in the 20th century. It is not historically or technologically significant. Nor is the highway noteworthy. US 19, the Perry Highway connected Pittsburgh and Erie on a meandering route that passed through only one major town along the way. The route was a minor carrier of north-south traffic. Discussion of Surrounding Area The bridge carries a 2 lane road in a mixed use setting of scattered commercial and residential buildings that lacks the cohesiveness of a potential historic district. Most buildings date from the late 20th century. Bridge Considered Historic By Survey: Yes
Information From www.mercercotrussbridges.com Demolition Mitigation WebsiteWhen built, the bridge was an example of a standard-design, heavily constructed, Pratt Through Truss bridge. Subsequently, the upper lateral braces were moved to the exterior of the bridge, to help the bridge retain stiffness and to increase roadway clearance. Riveted connections were also added to high-strength bolts at some lower panel points. |
