John Greenleaf Whittier Memorial BridgeNewburyport and Amesbury, Massachusetts
Massachusetts Department of Transportation
As designer- and engineer-of-record, HNTB designed the John Greenleaf Whittier Memorial Bridge and Interstate 95 improvements as part of MassDOT's Accelerated Bridge Program. HNTB drew on extensive expertise in designing the innovative, network-tied arch bridge, which is one of only 14 in the U.S.
The accelerated schedule meant submitting multiple early-release packages and gaining consensus from both the contractor and owner. Tackling one of MassDOT's largest projects ever, HNTB focused on a constructability with a plan to build the John Greenleaf Whittier Memorial Bridge one span at a time and while preserving its architectural and historic elements. With its innovative, unique proposal, HNTB delivered several firsts for the client:
- network tied-arch bridge
- EPS wall
- shared-use path along a Massachusetts interstate
- innovative launch girder, gantry crane erection scheme
- application of an anchor system on a network-tied arch
- new Pine Hill Bridge featuring continuous, curved steel girders, variable skews at the ends, an intermediate pier and integral abutments
The design-build project expanded a 4-mile stretch of I-95 from three lanes to four in each direction, repaired and widened a major three-lane bridge and replaced or rehabilitated several other structures - all while maintaining six lanes of traffic to avoid major traffic backups. Despite numerous challenges, HNTB met every deadline, and, during the five-year construction period, there were no delays or cost overruns associated with design.