Lancaster Avenue over the East branch of the Brandywine Creek Bridge Rehabilitation
Project Location
Overview
The Pennsylvania Department of Transportation proposes rehabilitating the Lancaster Avenue Bridge (U.S. 322/Business U.S. 30) over the East Branch of Brandywine Creek in the Borough of Downingtown, Chester County. The existing bridge is a four (4) span, closed spandrel reinforced concrete arch bridge built in 1921. The bridge has a total length of 211 feet from end to end of wing walls with an out-to-out width of 54 feet. The structure carries three lanes of traffic with flanking sidewalks and balustrade railings. The bridge is structurally deficient, and we are proposing to rehabilitate it. It is in poor condition due to extensive spalling of the spandrel walls, arch barrels, and sidewalk/spandrel wall interface. Large void areas are in the existing earthfill below the pavement, and the balustrade railings exhibit sections leaning outward. There are widespread areas of cracked, delaminated, and spalled concrete on the substructure units. The bridge is currently weight-restricted to a maximum limit of 36 tons, except for combination vehicles of 40 tons. U.S. 322 is classified as a principal arterial highway with an ADT of 14,698 vehicles per day (2017).
The project scope is to rehabilitate the bridge by removing and replacing the sidewalks and balustrade railings, overhang brackets, portions of the spandrel walls and piers, performing concrete repairs, replacing the earth fill with lightweight concrete fill and placing a new bituminous wearing surface. The existing balustrade railings will be replicated with a precast concrete balustrade railing system with an exposed aggregate finish to match the existing railing finish. The sidewalks will be 6’-0” wide (transparent), and a new PA Type 10M bridge barrier will be placed between the roadway and the sidewalks. The new bridge will be 1’-6” wider on each side due to the addition of the PA Type 10M bridge barriers (57’-0” proposed out-to-out width). The bridge brackets will be reconstructed similarly long enough to support the wider superstructure. Also included in the scope of work is resetting the existing light fixtures, salvaging, restoring, and reinstalling the existing bridge plaques, placing scour protection as needed, and replacing the modern balustrade railing in the adjacent plaza with a railing that matches the one to be used on the bridge.
It is anticipated that one lane of traffic (westbound) will be maintained during construction, with eastbound traffic detoured.