Box-jack. Have you heard of it? No, not the burger, and definitely not the creepy musical clown that pops out at you. It’s yet another in a series of incredible firsts for the MTA as part of the LIRR Expansion Project: a revolutionary technique to install railroad bridges over underpasses, known in the construction industry as “box-jacking.” The box-jacking system was developed by an Italian contractor, Petrucco. Italy has quite a storied history of engineering feats, from the Coliseum to the Vatican and thousands of bridges and buildings in between — so you know this is legit.
The box-jacking system was used successfully for the first time ever in the USA at the Urban Avenue Grade Crossing in New Cassel over the weekend of July 20-21 and was deployed again during the weekend of August 24-25 for the elimination of the at-grade crossing along Covert Avenue. You can watch a timelapse video of the roll-in here.
Box-jacking reduces the length of time the tracks must be taken out of service. Using this approach, workers build a multi-ton (more than 100 tons, easily) concrete structure onsite comprising includes the rail bridge, the length of roadway beneath the bridge and the side walls connecting roadway below with rail bridge above. They then use powerful hydraulic jacks to inch the structure into place over the course of one weekend.
Box-jacking is changing the way the MTA delivers modernized infrastructure for a world-class transportation system – allowing our construction crews to complete these complex jobs faster and easier. 3TC and LIRR crews can now install railroad bridges over new underpasses in single weekends, dramatically minimizing interruptions to the hundreds of thousands of riders who rely on the LIRR every day — compared to the weeks, months or even years that these kind of projects used to take in the past. Up next, crews will utilize this innovative and transformative technique at three more grade crossing elimination projects: New Hyde Park Road in New Hyde Park, Willis Avenue in Mineola, and School Street in Westbury.
“The LIRR Expansion Project is transformative in so many ways, with construction techniques being no exception,” says Nick Almeter, Area Manager for 3TC. “We are thinking outside of the box and using ingenuity to solve the issue of how to construct a new bridge in one weekend. Jacking the ‘box’ eliminates multiple doubletrack outages that would be required using a conventional approach, reducing risk and minimizing the impact to the LIRR schedule.” Looks like the MTA has the elimination of further grade crossings in the LIRR Expansion Project corridor in the box!
The construction of a third track from Floral Park to Hicksville will reduce train congestion and delays and enable true bi-directional service during peak hours with a more reliable rail network. This transformative work includes several related projects, including the construction of parking garages, retaining walls, improvements to rail bridges and the removal of eight street-level grade crossings.
Construction is being managed to minimize the impact on daily routines, with extensive mitigation and public outreach efforts in local communities. For more information and photos, please visit the LIRR Expansion Project Floral Park to Hicksville project page on AModernLI.com.