Topic/subtopic: Transportation (Bridges)/Rehabilitation Target Audience: Bridge engineers/design practitioners, builders, educators and officials; professional and amateur historians; those interested in bridge design aesthetics. Take-Away Lessons from this Presentation: Two contrasting design approaches for arch bridges; an aesthetic program for a bridge rehabilitation design that is responsive to its historic context; and an interesting story about a historically significant bridge. The purpose of this project was to improve the Main Street crossing of the Dan River in the City of Danville. The existing seven-span, 823-foot long, four-lane concrete arch bridge carrying Main Street was designed by Daniel Luten and constructed during the late 1920s. It had deteriorated significantly and was in need of rehabilitation or replacement. Major traffic capacity improvements were needed on the crossing as well as the intersection at the north end of the bridge. Additional objectives were to maintain the historic integrity of the existing bridge and to affect as few businesses and residences as possible. The bridge is a contributing element to four historic districts that surround it. The Main Street/Riverside Drive intersection immediately north of the bridge was widened to accommodate future year traffic. Additional southbound lanes were constructed on a new two-lane concrete arch bridge located west of the existing bridge. Each span includes four parallel arches. The floor system is framed with AASHTO girders spanning from arch crowns to the adjoining substructure. The historic identity of the existing Main Street bridge was maintained by rehabilitating it in place. Existing concrete arches and piers were repaired while the spandrel columns , floor system and deck were replaced, in kind, with cast-in-place concrete. Its appearance will remain similar to the existing bridge by virtue of the arches and piers remaining. Architecturally designed form liners and pigmented concrete were also utilized. The intent of the aesthetic design is for both bridges to share common elements while having their own identity. A custom designed, open handrail was constructed on both bridges. The project was completed during 2006.
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