Durable and Compatible Concrete Repair of Historic Bridges

Focus Area

Historic Preservation/Cultural Resources

Subcommittee

Community & Cultural Concerns

Status

Current

Cost

$100,000-$249,000

Timeframe

Under 1 year

Research Idea Scope

Many bridges that have been determined eligible for the National Register of Historic Places possess concrete components in need of repair. The Secretary of Interior Standards for concrete repair cannot always be directly applied to concrete repairs on historic bridges to achieve a lasting repair due to issues of incompatible binding, differential flexibility, etc. This results in a situation where the need to make the lasting repairs competes with the need to preserve the historic integrity of the bridge, which in turn requires DOT, FHWA, and SHPO staff time to investigate and negotiate a reasonable compromise. Reconciling the need to make durable concrete repairs on historic bridges while making them compatible in appearance with adjacent historic materials will attend to both transportation and historic preservation goals. A comprehensive address of the issue would benefit all state DOTs who have an ever increasing amount of repair projects involving the concrete portions of their historic bridges. The study should involve bridge maintenance and repair specialists in state DOTs, repair consultants, AASHTO, FHWA, ACHP, National Park Service Preservation Standards staff, SHPOs and architectural historians experienced in historic bridge repair. The study should begin with a survey of state DOTs on and special historic bridge concrete repair techniques they employ, followed by a summary. Then identifying the gaps between SOI standards for concrete repair and specific repair techniques needed for concrete on historic bridges with a summary. Next an investigation of how to make lasting repairs to concrete that will satisfy both transportation needs and preservation of historic integrity, with a summary. The results should be organized into a guide that can be readily incorporated into the bridge repair manuals for state DOTs and quickly put to use.

Urgency and Payoff

The problem is extremely common among every state DOT and is certain to increase as historic bridges age and are subject to increasing transportation demands. Providing comprehensive assessment and guidance to this ubiquitous issue will allow State DOTs and their transportation partners quickly adopt lasting repair techniques of historic bridge concrete components and save much time that would otherwise be spent researching and negotiating repair techniques on a per case basis. The time and costs spent researching and coming to an agreement with historic preservation interests is great, especially multiplied by the dramatically increasing number of repairs by the number of historic bridges in each state. This time and expense can be dramatically reduced with comprehensive research and guidance that can be applied to most historic bridge concrete repair scenarios that may be adopted by state DOTs and accepted by SHPOs and other historic preservation interests.

Suggested By

Carey Coxe Louisiana Department of Transportation and Development 225-242-4520

[email protected]

Submitted

03/16/2021