The center span of the Roebling Bridge is 1057 feet between the two towers. At this location, you can get up close to the suspension cables and appreciate their size. The lower cable is the original iron strand cable that is slightly over 12 inches in diameter made up of over 5000 strands of wrought iron wire. The upper cable is the steel strand cable added in the 1890’s reconstruction and is 10 and a half inches in diameter made up of over 2200 strands of steel wire. Both cables are wrapped with a smaller diameter wire. An interesting feature of the original iron cable is that it was treated with linseed oil to prevent corrosion.
Both the original iron and added steel cables were built in place on the bridge using a unique ‘spinning’ process developed by John Roebling. This process uses a special traveler device that carries the wire strand back and forth from end to end of the bridge to construct the suspension cable out of a single long continuous wire. The continuous length is made by splicing the end of one wire to the beginning of the next and continuing the spinning process. This process is still used today in the construction of suspension bridge cables.
At the center of the span you can also see some of the features that allow for the expansion and contraction of the bridge during temperature changes. The steel roadway has a toothed expansion joint that looks similar to a comb to allow the two sections of the roadway to move relative to each other. There are similar expansion joints at each abutment at the end of the center span. Also on the edge of the roadway you can see a sliding truss section where the blue bridge paint is worn from sliding back and forth with the movement of the sections of the bridge.
The open grid steel road deck was installed on the bridge in the 1950’s, replacing the asphalt-covered wood deck which was prone to damage and deterioration due to weather. This steel grating results in the ‘singing bridge’ nickname due to the noise generated by vehicles driving over the bridge.
The Roebling Bridge was the only bridge in an 800 mile stretch of the Ohio River to remain open during the 1937 flood. During this record 80 foot crest of the Ohio River, the Cincinnati side was high and dry, and the Covington side remained accessible through the installation of a temporary sand and gravel ramp.
This automated tour is provided by the Covington Cincinnati Suspension Bridge Committee. The committee is a citizen volunteer group dedicated to the preservation and enhancement of the Roebling Bridge. The committee is responsible for the decorative lighting and flags on the bridge and for promoting public awareness of the bridge’s history. The committee is totally funded through public donations and membership fees. Please visit the committee web site at roeblingbridge.org and consider membership or a donation to help preserve and enhance this famous symbol of the Cincinnati area. The committee thanks you for your support.