The Major General Nathanael Greene Memorial Bridge was built in 1900 and reconstructed in the 1980s with a new superstructure. The original substructure sustained significant damage during a historic flood event, was deemed unsafe for passage, and closed.
Having created a substantial impact to the community, RIDOT recognized the urgency of the replacement and sought a fast solution to restore the connection. The project was quickly put out for bid under Rhode Island’s first ever Design-Build (DB) contract. CME, in collaboration with well-respected construction firm, Cardi Corporation, proposed the use of Accelerated Bridge Construction techniques to get the job done fast without sacrificing quality. The design team was selected to perform the work in Sept. 2011 and delivered final design documents including permits in March of 2012 for the beginning of the construction season. The bridge was opened to traffic in October 2012.
The bridge carries Laurel Avenue over the South Branch of the Pawtuxet River and the Anthony Mills Dam, which is a stone weir step outlet, is located approximately 10 feet upstream of the abutments. During the flooding, the north abutment, south abutment, and wing walls were all damaged and the superstructure was deemed unsafe. As a result, the team had to carefully dismantle the existing north abutment; construct new deep foundations and a new superstructure; reconstruct the existing concrete splash pad in the riverbed below the bridge; construct a scour revetment structure immediately downstream from the splash pad; and construct new roadway approaches for Laurel Avenue.
The new bridge is an 84 ft. span widened by 4 feet from its previous footprint to include room for the addition of sidewalks on both sides of the roadway. The project involved the replacement of the entire bridge structure using micropile supported cantilever abutments. The use of precast semi-integral abutments proved valuable in several ways by eliminating the time needed to form this component, having it also serve as the backwall, and allowing for the elimination of a formal bridge joint, leading to significant construction time savings. To comply with contract requirements, stones from the original abutments were used to veneer the new abutments.
In addition to water handling during construction, the team also designed a stable outlet for the dam to protect the new abutments from scour. A full width concrete slab was placed under the bridge and transitioned to a stone filter sized for the anticipated hydraulic flows to protect the channel and wingwalls downstream of the bridge.
CME provided a full suite of design and technical services throughout the project and construction was completed on budget and prior to the contract deadline to complete the construction.