Prospect Bridge

Information and Findings From Ohio's Historic Bridge Inventory

Setting/Context

The bridge carries a 2-lane highway over a stream in an area of 19th and early-20th-century residential and commercial development in Prospect.

Physical Description

The 1 span, 226'-long, pin-connected Parker thru truss bridge is traditionally composed of built-up compression members and eye bar or rod tension members. The bridge has lattice portals decoratively finished with a circular medallion plaque and wrought-iron crestline. The stringers and open-steel grid deck were replaced in 1985. It's unclear from the available photos but it appears floorbeams were replaced or connections strengthened. The bridge is supported on concrete abutments.

Integrity

Deck replacement (1985)

Summary of Significance

The pin-connected Parker thru truss was fabricated by the Standard Engineering Company in 1913. It is a complete and long-span example of its type/design in the state context. It has had a deck replacement, but that has not compromised its ability to convey its technological significance. A project was planned to replace the bridge in 1999 with an adverse effect, but the bridge is still in place in 2008. The eligible recommendation of the prior inventory remains appropriate.

Camelback and Parker trusses are members of the Pratt-family of trusses with sloped top chords Technologically, Camelback and Parker trusses differ only in the number of top chord slopes (Camelbacks have exactly five slopes, and Parkers have more than five slopes.) The sloped-chord trusses provide the greatest depth at midspan where it is needed to accommodate the stresses, meaning that less material is needed in their construction as compared to a parallel chord truss of similar span, but fabrication is made more difficult due to the varying lengths of the members. The sloped-chord trusses are often associated with longer spans where the savings in material is great enough to be worth the additional fabrication costs. The practice of sloping the top chords dates to at least the 1840s and appeared early in the development of metal trusses. As with other truss designs, pin connections were used from the 1870s to 1900s, and mostly phased out during the 1910s. Rivet connections were being used by the early 1900s and were prevalent from the 1910s to 1940s. Standardized rivet-connected Camelback and Parker designs were used by many state highway departments, including the Ohio State Highway Department. There are 23 trusses (8 Camelback, 15 Parker) in the Ohio inventory (Phase 1A, 2008).

Justification

The later pin connected thru truss bridge is one of 13 extant examples of bridges with polygonal upper chords and/or subdivided panels in the state that date from 1888 until 1923. It is of moderate significance given that the numbers in the population.

Bridge Considered Historic By Survey: Yes