Higginsport Bridge

Information and Findings From Ohio's Historic Bridge Inventory

Setting/Context

The bridge is closed to traffic. It carries a single-lane over a stream in a rural setting. To the west is a campground. The bridge appears to be on the alignment of a bypassed section of old US 52.

Physical Description

The 1 span, 176'-long, double-intersection Pratt (Whipple) truss bridge is supported on stone abutments with concrete repairs. The truss is traditionally composed with built-up compression members and eyebar tension members. The upper chords are toe-out channels with coverplate and battens. The verticals are toe-out channels with lacing. The diagonals are eyebars with loop-welded eyes. The lower chord eyebars have forged eyes. The interior panels have a mid-height strut of toe-out channels with lacing. The upper lateral bracing is composed of I-sections with a U-shaped clip to form the connection with the upper chords at the pins. The A-frame lattice portal bracing features decorative cast-iron moldings at the base of the brackets. U-shaped hangers at the lower panel points pick up built-up floorbeams. The floorbeams carry rolled stringers and a steel deck pan (non original). The bridge has pipe railings with many sections missing.

Integrity

The end posts at the west end have been strengthened with channel sections welded to the interior. The counter rods at mid-span have snapped. Snapped diagonals in two panels on the upstream side have been repaired with the addition of cables. Rods have been added to strengthen the end panels of the lower chords. The alterations and lack of maintenance are having an impact on the integrity of the design/materials, but sufficient integrity remains for the bridge to convey its technological significance.

Summary of Significance

The ca. 1885 double-intersection Pratt truss is a technologically significant example of an increasingly uncommon truss type/design (Criterion C). The builder is undocumented by available county records. Double-intersection Pratt trusses, also known as Whipple or Murphy-Whipple trusses, were among the most successful of long-span thru truss designs (up to 300' long) of the 1860s to 1890s for both railroad and vehicular crossings. Surviving examples are uncommon nationally and considered technologically significant; Ohio with at least 14 identified examples dating from 1881 to 1898 (Phase 1A survey, 2008) has a very high number in comparison to most other states. The truss design is characterized by diagonals that extend over two panels. In 1847, Squire Whipple, one of America's foremost bridge engineers, developed the design figuring that the double-intersection configuration increased the depth of panel without altering the optimal angle of the diagonals, thus allowing for increased span length. His design was further refined in 1859 by John W. Murphy, the talented chief engineer of Pennsylvania's Lehigh Valley RR, who substituted wrought-iron pins for cast-iron connecting pieces, thus developing the connection detail that would prove to be advanced construction practice for this and other truss designs for the next several decades. Ohio's surviving examples, which mostly date to the 1880s, were not cutting edge for their time, but they show how the form had evolved into the preferred long-span thru truss design of the period. Most have documented associations with prominent Ohio-based fabricators.

Justification

There are at least 14 examples of the bridge type important to the development and maturation of the pin-connected thru truss bridge (Dec. 2009). They date from 1881 and concentrate in the 1880s. Even though there are more than 12 extant examples in Ohio, each built in the 1880s has high significance based on overall scarcity (everywhere but in Ohio) of the design. This is a major and technologically significant bridge type. The bridge has high significance.

Bridge Considered Historic By Survey: Yes