About this Project
LKB was retained by Westchester County Department of Public Works to provide construction management and construction inspection services for this bridge replacement project. The historic Crane Road Bridge was comprised of two bridges, both carrying the Bronx River Parkway through the Bronx River Parkway Reservation in the Village of Scarsdale and the Town of Greenburgh in Westchester County, NY. The southern bridge was a multi-span concrete “Mushroom Bridge” that crossed the Bronx River, while the northern bridge was a single span steel through-girder bridge that crossed the two track Metro-North Railroad Harlem Line (“MNR Bridge”). Constructed in 1925, both bridges had undergone numerous rehabilitation programs, however had become increasingly deteriorated. In addition, traffic safety along the Bronx River Parkway within the project limits was a major concern. Narrow travel lanes, minimum shoulders, sharp curves, and limited sight distance created a condition where the rate of highway accidents was more than 6 times the statewide average.
To address safety concerns, geometric changes were incorporated into the replacement structures. By increasing the overall bridge width, all four travel lanes and shoulders were widened. Acceleration/Deceleration lanes were increased dramatically. The curved alignment was also softened in order to improve sight distances. Additionally, a merging roadway was raised so that drivers on the Bronx River Parkway and the merging roadway can easily see one another and merge safely. Numerous challenges included several piers located inside of the Bronx River, complicating construction and approvals. Also crossing the river is a sanitary sewer pipe, constructed in the early 1900’s, which could not be re-routed. As a result, several pier footings were affected. Two of the six spread footings were designed to span over the top of the sewer pipe.
In order to provide the roadway improvements without negatively affecting the river or hampering water flow, the bridge deck was widened, but the piers remained relatively the same size. As a result, the cantilever brackets were significantly lengthened in comparison to the original bridge. A reinforced concrete solution such as the original, proved infeasible due to rebar congestion. An innovative steel solution was designed, in which steel brackets connected to a steel core, which in turn was secured to the concrete bridge pier. The surfaces were clad in existing and new architectural stone.
LKB’s services included detailed inspection, on-site field testing of materials and other construction activities, including field measurement and collection of data, submission of monthly and final estimates and progress reports, and preparation of record plans showing all changes from the contract plans. The construction management/inspection services included overseeing all construction operations and the placement of Work Zone Traffic Control.
Westchester County Department of Public Works
This article was originally published by LOCKWOOD, KESSLER & BARTLETT, INC. (LKB), a wholly-owned subsidiary of The Vertex Companies, LLC since January 2021.