Built to provide decades of additional reliable service and improve the safety and access to maintain the bridge operating systems, the Harlem River Lift Span on the RFK Bridge is a 310-foot Warren truss tower drive vertical lift bridge that raises to allow marine traffic pass through on the Harlem River. The HRLS carries six lanes of vehicular traffic and two sidewalks between Manhattan and Randall’s Island to the Bronx and Queens. Work included upgrading the lift span operating system, the installation of a new standby generator and related equipment to provide an auxiliary source of power, as well as rehabilitation of the rack and pinion driven tower elevators. Improving maintenance access, upgrading walkways and ladders, and installing new designated tie-off points for maintenance personnel were all important aspects of the project. This project also included innovations that further reduced maintenance requirements, specialty-made electrical boxes, and warning gates accessible from one side to more safely maintain equipment.
Innovation Helps Connect Communities
The Harlem River Lift Span is a large, complex movable bridge, which meant that the design-build team needed to be proactive and develop a short, efficient construction
schedule along with making repairs less complex, simpler to fabricate and easier to install on the bridge and reduce long-term maintenance. Key innovations in certain areas encouraged the Owner to implement those ideas and innovations on other projects, including replacing the specified automatic lubricating system for the main and auxiliary counterweight guides with lubrication-free guides made with solid engineered nylon polymer. Rather than taking the bridge out of service to replace four rack pinion gears, the team was able to recondition all eight pinions to provide the required 20-year life. The design-build team maximized the DB model by striving for innovation, creativity and outside-the-box thinking throughout the design development. Thanks to that collaborative success, the HRLS was completed five months ahead of schedule.
|MTA Bridges and Tunnels (MTAB&T)
|HNTB NY Engineering and Architecture, P.C.
Photo Credit: J. Wasielewski, HNTB