Allerton Road Bridge

Information and Findings From Pennsylvania's Historic Bridge Inventory

Discussion of Bridge

The one-span, 105'-long, steel, Pratt thru truss bridge, built ca. 1905, has built-up members, lattice railings, and is supported on stone abutments. The upper chord-diagonal connections have bolts replacing original rivets at the gusset plates, but the lower chord connections are still riveted. U-shaped floorbeam hangers pick up rolled floorbeams and pass over saddles at the lower chord connections. According to county records, the truss bridge was moved to this site from another location in 1953. It is representative of the transition period from 1895 to 1905 when riveted connections replaced pinned connections as the dominant type of metal truss bridge connection. U-shaped floorbeam hangers, a detail most often associated with pin connected bridges, are an important transition detail. Riveted truss bridges with Ushaped floorbeam hangers are not common. Relocation did not result in significant alterations. It is an individually significant example of its type and design. The bridge is evaluated in the 1995 Worth-Jefferis HD nomination as a noncontributing resource based on the fact that it was placed at its present location in 1953, and thus postdates the district's 1707-1943 period of significance. The bridge was not, however, evaluated based on its own individual merits, and in fact is misidentified as a "steel trestle." The nomination also did not note that the bridge is an older structure that was relocated.

Discussion of Surrounding Area

The bridge carries 1 lane of a 2 lane road over a stream in a rural setting with open fields to all four quadrants. The bridge is located in the Worth-Jefferis HD, an 1,800 acre rural historic district that is significant in the areas of exploration, agriculture, and architecture with a period of significance of 1707-1943.

Bridge Considered Historic By Survey: Yes