Planning the replacement of the Beards Creek bridge

摘要

US Route 20A crosses Beards Creed, a tributary ofthe Genesee River, in the hamlet of Cuylerville near the Town ofGeneseo in western New York. In early March 1994 fresh water(>20 mgd) began entering the Retsof Salt Mine ca 1100 feetbeneath the bridge. Despite efforts to stop the inflow, itcontinued until early 1996 when the mine became completelyinundated. Since March 1994, the bridge crossing the creek hassettled 15 ft and move ca f ft upstream toward the smaller of twolarge-diameter sinkholes centered on the creek which haddeveloped ca 400 and 1300ft upstream of the bridge. Both priorto and during the inundation of the mine, the owner of the mineand several public agencies conducted an extensive array ofsurface measurements, hydraulic surveys, subsurfaceinvestigations and predictive impact studies. Upon developmentof the sinkholes and the initial settlements, the bridge wasdeclared unsafe and taken out of service. Public need andpotential archeological resources in the immediate environs ofthe bridge require that the bridge be replaced, at its presentlocation, with little or no taking of additional right-of-way.The suthors's firms have been engaged in designing thereplacement bridge and the restoration of the approach roadways.Their work has included the review and interpretation of the dataand findings of the numerous studies conducted at and near thebridge site. They have used these reviews and interpretations as abasis for the hydraulic and foundation design for the fridgereplacement and roadway restoration. This paper presents asummary of their design approach and rationale.