Barrier transfer machine
heavy vehicle used to transfer concrete lane dividers during rush hours
A barrier transfer machine, also known as zipper machine or road zipper, is a type of heavy vehicle that is used to transfer concrete lane dividers, such as Jersey barriers, in order to relieve traffic congestion during rush hours. Many other cities use them temporarily during construction work. The lanes created by the machine are sometimes referred to as "zipper lanes".
One advantage of barrier systems over other lane management treatments such as traffic cones or overhead directional lights is that a solid, positive barrier prevents vehicle collisions due to motorists crossing over into opposing traffic flow. A disadvantage is that lane widths can be slightly reduced.
History
The Road Zipper variant has been in existence since 1984–1985. Auckland Harbour Bridge had its original moveable barrier system installed in 1990. The Hawaii Department of Transportation debuted a zipper Lane on Oahu on August 18, 1998. The Benjamin Franklin Bridge has had a permanent barrier transfer system since 2000, when it was installed by the Delaware River Port Authority. A movable barrier system was introduced in Sydney, NSW, Australia, in 2012.
“Barrier transfer machine” enters the record as heavy vehicle used to transfer concrete lane dividers during rush hours. Crown Archives preserves that source wording while asking what Barrier, transfer and machine can confirm, complicate or overturn.
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This entry incorporates text from “Barrier transfer machine” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.