The Minnesota Department of Transportation will try for the first time overnight Wednesday a new technique that will effectively "push" the new Larpenteur Avenue bridge into place, the Star Tribune reports.
The move involves hydraulic jacks and concrete shoes with Teflon pads underneath to give the bridge some glide. The DOT will close both directions of I-35E between I-94 and Hwy. 36 during the what is called the "slide-in bridge construction" from 9 p.m. Wednesday to 5 a.m. Thursday.
An innovation of the Federal Highway Administration, the "slide-in bridge" technique has previously been used in Oregon, Utah, Missouri, Michigan, Colorado and Massachusetts, and other states may try it as well, the Star Tribune says.
The FHA has detailed information on slide-in bridge construction, also known as "lateral slide" construction.
The DOT estimates the construction time of the old Larpenteur Avenue bridge to the new one will be shortened to an estimated 35 days in comparison to 60 days for bridges of a similar size, like the bridges recently constructed at Arlington Avenue and Wheelock Parkway. The beams and decks of those bridges were moved in laterally and vertically.
The Pioneer Press says the bridge beams and deck for the slide-in project – which weigh 3.5 million pounds – were constructed just four feet north of the existing Larpenteur Avenue bridge framework; unlike the Arlington Avenue and Wheelock Parkway, which were constructed off-site.
The construction of the bridges is part of the MnDOT's "MnPASS Project."