Pyrmont Road Bridge Rehab
Lewisburg, OH United States | 2020
Crossing a tributary of Sycamore Creek, this attractive 94’ bridge in length was built in 1888 by the Queen City Bridge Company, perhaps the only surviving example of a bridge built by this company. It is a pin connected Pratt through truss bridge. The structure is composed of six panels. It is most noted for its slight skew, rare among pin-connected truss bridges. Although modern railings are in front, the original pipe railings remain behind them. They are highly unusual because they pass through the vertical members, and the end posts.
This railing design is clear evidence that railings in this era were not built with protecting the trusses in mind. The Hamilton County Engineer's office, along with the Village of Indian Hill, knew the bridge needed to be rehabilitated in order to keep it in service. The plan included replacing the load bearing beams with concrete and utilizing the existing steel trusses while widening the bridge slightly and reinstalling them.
The success of this galvanized bridge rehab project will help future generations enjoy the beauty of the historic steel truss bridge for decades to come.
Hamilton County built a beam bridge underneath the truss bridge, making the truss essentially decorative and non-functional for supporting the load of vehicles. Another perspective is that this method eliminated the need to repair or retrofit the truss to continue to support traffic at a high weight limit. Thus, it limited alterations to the original truss design and materials. This example of adding beams under the bridge was especially unobtrusive because the beams were added under the floor beams. Sometimes the floor beams would be removed with this method, which would alter the bridge, but this was not the case here.
The galvanizer was involved early on in the project to recommend proper preparation of the existing beams and trusses for hot-dip galvanizing. Both the County and the City had many concerns over how the 134 year old steel bridge would react to today's hot-dip galvanizing process. Several sample pieces were presented and aesthetic questions were answered based on previous bridge rehab projects and helpful documentation from the American Galvanizer's Association technical department. The success of this galvanized bridge rehab project will help future generations enjoy the beauty of the historic steel truss bridge for decades to come.
Bridge & Highway
Indian Hill, OH United States
Coating Durability, Corrosion Performance, Life-Cycle Cost
Beams, stringers, plate, channel
Evers Steel Construction
Johnson, Mirmiran & Thompson Engineers
V&S Columbus Galvanizing
Thank you! Your vote has been accepted.