Bridge No: 0170015900100

Asset ID: 2108

County: Abbeville

Facility Carried: S-1-159 (Millers Mill Road)

Feature Intersected: Long Cane Creek

Year Built: 1955

Main Structure Type: Pony Truss

Design: Warren (Bolted)

Main Material: Steel

Railing Type: Rail High Steel Angle Railings

Number of Main Spans: 1

Structure Length: 151 feet

Structure Width: 14 feet

Setting: The bridge carries a single lane unimproved road over a stream in a wooded rural setting.The bridge is located in the Sumter National Forest.

The 4-span, 151'-long bridge consists of an 80'-long Warren pony truss and 3 steel stringer approach spans. The truss span has polygonal upper chords The truss has paired angles for the lower chords and I-shaped sections for the polygonal upper chords, diagonals, and verticals. The members are connected by high-strength bolts at the gusset plates. The rolled floorbeams support stringers and a wood plank deck. The bridge has 2-rail high angle railings and is supported on solid-stem concrete piers that appear to date to a previous bridge.

The Warren pony truss bridge dated 1955 by SCDOT stands as one of the earliest extant examples of the type and design that came to dominate pony truss design in South Carolina and across the nation after World War II. With improvements in metallurgy and rolling technology, both rolled H and I section came into common use for chords and web members starting nationally in the late 1920s and in South Carolina by 1936 (see 0490128500100). Having a rolled rather than a built-up section eliminates plate-to-plate connections and opportunities for moisture-penetration corrosion. Use of rolled section dominated pony truss construction after World War II and continues to this day. As one of the earliest documented example of the important postwar transition to all rolled section member spans, the bridge is historically and technologically significant within the state context. It meets criterion C.