The Shippee Bridge, Rhode Island Department of Transportation (RIDOT) Bridge No. 307, carries Sherman Farm Road (RI Route 98) over the Nipmuc River just north of the village of Harrisville in the town of Burrillville, Rhode Island. The proposed structure will utilize the existing abutments which will accommodate new 74-foot-long prestressed box beams to support the 28-foot-wide roadway. Minor modification to the bridge beam seats and backwalls will be required to support the new bridge superstructure. The new approach slabs will be constructed behind the backwalls. The sidewalk will be constructed on the west side of the bridge. To support the sidewalk, a 92-foot-long prestressed box beam will be placed on the modified wingwalls. The modifications required to the existing beam seats, backwalls, and wingwalls will not encroach upon the wetland limit; however, all proposed work will take place within the 200-foot riverbank wetland.
The new superstructure will consist of five BI48 and two BI36 prestressed deck box beams. These new box beams will fit within the existing available bridge seat width. To provide for two 12-foot-wide lanes with a 2-foot-wide shoulder on each side, an 8-inch-thick cast-in-place deck or precast deck will be placed onto the box beams. The maximum overhang of the deck will be 2 feet x 9.25 inches on each side. The deck and box beams will be constructed to act as a composite section to minimize the required depth of the beams. This will ensure that at a minimum, the existing hydraulic opening is maintained. A waterproof membrane will be installed to protect the concrete deck followed by a 3-inch bituminous pavement overlay, which is proposed to prevent damage to the concrete deck from scarification during future cold planing and resurfacing operations. The deck will be extended beyond the backwalls to prevent leakage onto the beam seats and beam ends through the deck joints. The total width of the bridge superstructure which will support the vehicular traffic will be 31.5 feet with a 28-foot clear roadway width. The approach slabs will be constructed for the full roadway width behind each backwall. The replacement structure will utilize accelerated bridge construction method for minimal disturbance to traffic.
A 6-foot-wide sidewalk will be provided on the west side adjacent to the new superstructure. Since a bridge seat is not available to support the new sidewalk beam, the beam will be supported on the modified wingwalls. The sidewalk beam will be 92-feet-long and will consist of a single BI48 prestressed box beam. The wingwalls will be modified slightly at the back and top sides to accommodate the placement of this longer beam. A 6-inch-thick deck will be cast on this beam for the 6-foot sidewalk width. Pedestrians using the sidewalk will be protected with a pedestrian railing on the west side and a bridge parapet on the east side. The sidewalk deck and bridge parapet will not be connected due to the differential movement of the two structures. The parapet located on the east side of the bridge will be aligned with the fascia of the existing southeast retaining wall. Therefore, lengthening of the abutments and retaining wall will not be necessary. However, modifications will be required to the concrete seats, concrete backwalls, and the retaining wall to accommodate the new bearings, deck expansion joints, and parapets.
- Historical Preservation
- Scour Analysis
- Accelerated Bridge Construction Method