This is the Second Oldest Covered Bridge in the US

Roberts Covered Bridge, Eaton Ohio

Date added: November 15, 2023 Categories: Ohio Bridges Covered Bridges Burr Arch

The Roberts Covered Bridge, erected in 1829, is the oldest covered bridge extant in Ohio and the second oldest covered bridge remaining in the United States. It is also the only covered, double-barrelled span (two-lane) bridge remaining in the state. It was built by Orlistus Roberts, who did not live to see it finished, and Joseph Campbell for traffic on the Hamilton and Eaton Turnpike, which was privately owned and operated under authority granted by the Ohio State Legislature. It was built as a toll bridge.

Today, this bridge is still in use, although the once heavily-traveled road on which it stands was long ago abandoned in favor of Ohio 127, which is located just west of Old Camden Road. The bridge is in good condition.

On June 24, 1962, a historic site marker was dedicated at the bridge. This marker was sponsored by the Ohio Society of Professional Engineers and honors all Ohio covered bridges and their builders.

Bridge Description

Theodore Burr, a relative of Aaron, was born in New England, but lived most of his life in Harrisburg, Pennsylvania. He began to build bridges shortly after 1800 in the form of a combination of arch and truss. He patented this structural system in 1817. His was not a new idea, for Wiebeking in Bavaria and Gauthey in France had previously been designing bridges by this system. Condit describes the Burr system as follows: "The Burr bridge consisted of two separate parts: the main member was a flat truss with parallel top and bottom chords and either single or double diagonals; distinct from it were two timber arch ribs, one on each Side of the roadway, either outside or inside the truss plane. Thus the total load was distributed between the truss and the arches." Burr's system had one major defect, true of a sizeable number of bridge designs of the day, the structures were structurally indeterminant. It was impossible to make an accurate analysis of stresses in the individual truss members, because of the combination of truss and fixed arches.

The two-lane construction of the Roberts Bridge is unique in Ohio. It consists of 3 trusses strengthened by Burr arches. The clear span is 73 feet, each lane is 11-1/2 feet wide and the bridge itself is 91-1/2 feet in length. When the bridge was built, the clear span was 75' but the north abutment was badly damaged by flood water, very likely during the severe 1886 storm, and when a new abutment was built, it shortened the clear span to 73'. The structure is protected by a gable roof and horizontal siding. The bridge has been re-sided and re-floored.

The posts are 9" by 9" poplar, except for a 9" by 10" oak post in the center of each truss. The upright braces are 7" by 9" poplar, and the arches 6" by 15" poplar. All of the poplar timbers are planed to a smooth finish. The remainder of the framework is white oak and beech, top chords 6" by 9", bottom chords 6" by 11", floor beams 7" by 8", and floor joists, sway braces and roof structure heavy white oak and beech timbers. The top of each arch is 11'-6" above the floor. The third truss was used purely for structural reasons, not for the purpose of creating a two-lane bridge.