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A Jersey barrier or Jersey wall is a modular concrete or plastic barrier employed to separate lanes of traffic. It is designed to minimize vehicle damage in cases of incidental contact while still preventing the crossover case of a head-on collision. Jersey barriers are also used to reroute traffic and protect pedestrians during highway construction, as well as temporary and semi-permanent protections against landborne attack such as suicide vehicle bombs. A Jersey barrier is also known in the western United States as K-rail, a term borrowed from the California Department of Transportation specification for temporary concrete traffic barriers, or colloquially as a Jersey bump. Plastic water barriers of the same general shape are also now commonly referred to as Jersey barriers. ==Development and use== The Jersey barrier, also called New Jersey wall, was developed at the Stevens Institute of Technology in the 1950s (introduced in current form in 1959),〔(【引用サイトリンク】title=New Jersey Median Barrier History )〕 New Jersey, United States, under the direction of the New Jersey State Highway Department to divide multiple lanes on a highway. A typical Jersey barrier stands tall and is made of steel-reinforced poured concrete or plastic.〔Federal Highway Administration (FHWA). Washington, D.C. ("Concrete Barriers." ) FHWA Safety Programme. 2010-09-24.〕 Many are constructed with the embedded steel reinforcement protruding from each end, allowing them to be incorporated into permanent emplacements when linked to one another by sections of fresh concrete poured on-site. Their widespread use in road construction has led to wide application as a generic, portable barrier during construction projects and temporary rerouting of traffic into stopgap carpool and rush hour reversing highway lanes. The design of the Jersey barrier was specifically intended to minimize damage in incidental accidents and reduce the likelihood of a car crossing into oncoming lanes in the event of a collision. In common shallow angle hits, sheet metal damage is minimized by allowing the vehicle tires to ride up on the lower sloped face. Head-ons are minimized by gradually lifting the vehicle and pivoting it away from oncoming vehicles and back into traffic heading in its original direction. Modern variations include the constant slope barrier and the F-shape barrier. The F-shape is generally similar to the Jersey barrier in appearance but is taller with somewhat different angles.〔 The UK equivalent is the concrete step barrier. First tested in 1968 by the then Department of Highways in Ontario, Canada, the Ontario Tall Wall is a variant of the Jersey barrier. Standing at , it is taller than the standard Jersey barrier. In Ontario, the Ministry of Transportation is replacing guiderails (steel guardrail and steel box-beam) with these barriers on 400-series highways. The New Jersey Turnpike Authority developed and tested a similar, but heavily reinforced, design. This barrier design has been credited with effectively containing and redirecting larger vehicles, including semi-trailer (tractor-trailer) trucks.〔 The states of New York, Massachusetts, and New Jersey have adopted the taller barrier for their roads, as compared to the standard suggested by the Federal Highway Administration.〔 Designs with two rectangular notches at the bottom (through the short axis) allow for forklift-style lifting by front-end loaders. Barriers meant for short-term placement—especially in military and security barrier uses—might include steel rebar loops embedded in the top surface for rapid hook-and-cable system lifting. The 2010 G-20 Toronto summit used a modified modular Jersey barriers with wired fencing bolted onto the concrete. The fence used the barrier as sturdy base to prevent protesters from toppling the fence around the security zone at the Metro Toronto Convention Centre. The U.S. military nicknamed the devices as "Qaddafi Blocks" after truck bomb attacks in Beirut in 1983 resulted in more widespread use in military installations. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Jersey barrier」の詳細全文を読む スポンサード リンク
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