Thinking outside the box and learning the ins and outs of construction machinery contributed to the solution Almeter and his design-build team devised for replacement of the Park Avenue Viaduct in uptown Manhattan. They got equipment maker Mi-Jack Products, Inc. to custom-build the biggest pair of gantries possible to place 190,000-lb prefabricated bridge segments. Over 19 weekends, crews performed 128 bridge installations equaling 8,240 track-ft for the 132-year-old structure, all without disrupting Metro-North train service.

Matt Moran, chief engineer with Mi-Jack, recalls the request in 2022 for a custom 200‑ton rubber-tired gantry crane. "The MJ200HD model was selected as the ideal solution, designed to straddle both sides of the rail and minimize ground footprint, reducing roadway closures from four lanes to two—an otherwise impossible task in the dense environment of North Manhattan," he says.

Oversized components were shipped from Hazel Crest, Illinois, to 125th Street for preassembly, then staged on 119th Street for precise placement along Park Avenue, Moran adds. Column and side beam positions were aligned within ¼ inch for structural connections, verified by 50 surveyors before installing the 82,000-lb top beams across the four elevated tracks. "Precise load control was essential for aligning 130-ton bridge assemblies within 1/8 inch, ensuring accurate track alignment under tight time constraints," he says.

Crews built structural supports underneath the existing viaduct. Then, two of the four tracks of the viaduct were taken out of service. Using a moveable, 200-ton capacity gantry, crews cut and removed sections of the existing structure, with the rest of the structure supported on a temporary bracing system.

The first, $590-million phase finished last fall. Owner New York Metropolitan Transportation Authority stated that the project overall is $93 million under budget and 51 months ahead of schedule.

The gantries “solved a lot of the logistical constraints of the project,” says Almeter. “It allows us to stage trucks beneath the viaduct, load them efficiently for the demolition, and stage units up to three blocks away and move them 900 feet.”

This isn’t Almeter’s first foray into an out-of-the-box solution for a major rail project. In 2019, the team of Dragados USA, John P. Picone, Halmar International and CCA Civil utilized a box-jacking method developed by an Italian engineer to move multiple rail crossings for the Long Island Rail Road’s $2.6-billion 3rd Track Program, with only weekend shutdowns (ENR 9-2/19, p. 18). The box-jacking system from Petrucco utilized hydraulic jacks and spreaders to move a cast-in-place concrete box carrying the entire underpass and rail bridge into place in a matter of hours.

Almeter recalls going through the proposal phase with the design team led by Stantec. “One of the guys from Europe said, maybe we can do something that’s done there. I’m like, well, bring [the inventor] in.” Crews cast on site a concrete box consisting of a 112-ft by 40-ft reinforced concrete slab, with 24-ft side walls and two spans on top bearing rail and a roadway. The 2,000-metric-ton concrete box was cast on site, and then slid 58 ft into its final place. It was the first use of the method in the U.S.

Almeter says that such accelerated bridge construction techniques are a passion for him. “The rail industry in New York City has latched onto ABC, and I enjoy it. I’ve replaced 14 or so bridges that way, but the Park Avenue Viaduct takes it to whole new levels.”

Anthony Tufano, senior vice president for railroads with MTA Construction & Development, has worked with Almeter on both projects. “I have not encountered a more competent, prepared and dedicated project lead from any design-build team,” he says. “Nick brings an innovative and comprehensive approach to project delivery, leaving no stone unturned during planning and execution. He consistently evaluates the most efficient methods to deliver successful projects while ensuring that railroad operations are maintained and community impacts are carefully managed.”