A
Jersey barrier or
Jersey wall is a modular
concreteConcrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...
barrier employed to separate lanes of
trafficTraffic on roads may consist of pedestrians, ridden or herded animals, vehicles, streetcars and other conveyances, either singly or together, while using the public way for purposes of travel...
. It is designed to both minimize vehicle damage in cases of incidental contact while still preventing crossover in the case of head-on accidents.
Also utilized extensively to re-route traffic and protect pedestrians during
highwayA highway is any public road. In American English, the term is common and almost always designates major roads. In British English, the term designates any road open to the public. Any interconnected set of highways can be variously referred to as a "highway system", a "highway network", or a...
construction, such barriers are increasingly deployed in anti-terrorism roles as both quick fixes and semi-permanent protections against perceived landborne threats.
Jersey barriers are known colloquially by a variety of names in the U.S., including
Jersey bumps and, in the western states,
K-rail --a term borrowed from the
California Department of TransportationThe California Department of Transportation is a government department in the U.S. state of California. Its mission is to improve mobility across the state. It manages the state highway system and is actively involved with public transportation systems throughout the state...
specification for temporary concrete traffic barriers.
Development and use
The Jersey barrier was developed at
Stevens Institute of TechnologyStevens Institute of Technology is a technological university located on a campus in Hoboken, New Jersey, USA – founded in 1870 with an 1868 bequest from Edwin A. Stevens. It is known for its engineering, science, and technological management curricula.The institute has produced leading...
in
HobokenHoboken is a city in Hudson County, New Jersey, United States. As of the 2010 United States Census, the city's population was 50,005. The city is part of the New York metropolitan area and contains Hoboken Terminal, a major transportation hub for the region...
,
New JerseyNew Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
,
United StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
, under the direction of the
New Jersey State Highway DepartmentThe New Jersey Department of Transportation is the agency responsible for transportation issues and policy in New Jersey. It is headed by the Commissioner of Transportation...
to divide multiple lanes on a highway. A typical Jersey barrier stands 32 inches (81.3 cm) tall and is made of
steel-reinforced poured concreteReinforced concrete is concrete in which reinforcement bars , reinforcement grids, plates or fibers have been incorporated to strengthen the concrete in tension. It was invented by French gardener Joseph Monier in 1849 and patented in 1867. The term Ferro Concrete refers only to concrete that is...
. 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 general construction projects and temporary re-routing of traffic into stopgap carpool and rush hour reversing highway lanes.
The design of the Jersey barrier was specifically intended both to minimise damage in incidental accidents and reduce the likelihood of a car crossing into oncoming lanes in the event of a
collisionA collision is an isolated event which two or more moving bodies exert forces on each other for a relatively short time.Although the most common colloquial use of the word "collision" refers to accidents in which two or more objects collide, the scientific use of the word "collision" implies...
. In common shallow angle hits
sheet metalSheet metal is simply metal formed into thin and flat pieces. It is one of the fundamental forms used in metalworking, and can be cut and bent into a variety of different shapes. Countless everyday objects are constructed of the material...
damage is minimised by allowing the vehicle
tireA tire or tyre is a ring-shaped covering that fits around a wheel rim to protect it and enable better vehicle performance by providing a flexible cushion that absorbs shock while keeping the wheel in close contact with the ground...
s to ride up on the lower sloped face. Head-ons are minimised 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 barrierA constant slope barrier is a traffic barrier made of reinforced concrete and designed with a single slope that is used to separate lanes of vehicular traffic...
and the
F-shape barrierThe F-shape barrier is a concrete crash barrier, originally designed to divide lanes of traffic on a highway. It is a modification of the widely-used Jersey barrier design, and is generally considered safer....
. 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 barrierA concrete step barrier is a safety barrier used on the central reservation of motorways and dual carriageways as an alternative to the standard steel crash barrier.The barrier has contained all vehicles up to 13.5 tonnes.-United Kingdom:...
.
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 42 inches (106.7 cm), it is 10 inches (25.4 cm) 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 highwaysThe 400-series highways are a network of controlled-access highways throughout the southern portion of the Canadian province of Ontario, forming a special subset of the provincial highway system. They are analogous to the Interstate Highway System in the United States or the British Motorway...
.
The
New Jersey Turnpike AuthorityThe New Jersey Turnpike Authority is a state agency responsible for maintaining the New Jersey Turnpike and the Garden State Parkway...
developed and tested a similar, but heavily reinforced, design. This barrier design has been credited with effectively containing and redirecting larger vehicles, including
semi-trailerA semi-trailer truck, also known as a semi, tractor-trailer, or articulated truck or articulated lorry, is an articulated vehicle consisting of a towing engine , and a semi-trailer A semi-trailer truck, also known as a semi, tractor-trailer, or (in the United Kingdom and Ireland) articulated truck...
(tractor-trailer) trucks. The states of
New YorkThe New York State Department of Transportation is responsible for the development and operation of highways, railroads, mass transit systems, ports, waterways and aviation facilities in the U.S...
, Massachusetts, and
New JerseyThe New Jersey Department of Transportation is the agency responsible for transportation issues and policy in New Jersey. It is headed by the Commissioner of Transportation...
have adopted the taller barrier for their roads, as compared to the standard 32 inches suggested by the
Federal Highway AdministrationThe Federal Highway Administration is a division of the United States Department of Transportation that specializes in highway transportation. The agency's major activities are grouped into two "programs," the Federal-aid Highway Program and the Federal Lands Highway Program...
.
Designs with two rectangular notches at the bottom (through the short axis) allow for forklift-style lifting by
front-end loadersA loader is a heavy equipment machine often used in construction, primarily used to load material into or onto another type of machinery .-Heavy equipment front loaders:A loader A loader is a heavy equipment machine often used in construction, primarily used to load material (such as asphalt,...
. Barriers meant for short-term placement --especially in military and security barrier uses-- might include steel
rebarA rebar , also known as reinforcing steel, reinforcement steel, rerod, or a deformed bar, is a common steel bar, and is commonly used as a tensioning device in reinforced concrete and reinforced masonry structures holding the concrete in compression...
loops embedded in the top surface for rapid
hook-and-cable systemA lifting hook is a device for grabbing and lifting loads by means of a device such as a hoist or crane. A lifting hook is usually equipped with a safety latch to prevent the disengagement of the lifting wire rope sling, chain or rope to which the load is attached.A hook may have one or more...
lifting.
The
2010 G-20 Toronto summitThe 2010 G-20 Toronto summit was the fourth meeting of the G-20 heads of government, in discussion of the global financial system and the world economy, which took place at the Metro Toronto Convention Centre in Toronto, Ontario, Canada, during June 26–27, 2010...
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 CentreMetro Toronto Convention Centre , located in Downtown Toronto, Ontario at 255 Front Street West, has of space. The convention centre was completed in October 1984 and is home to the 1330-seat John Bassett Theatre...
.
Plastic Jersey barriers
Hollow
polyethylenePolyethylene or polythene is the most widely used plastic, with an annual production of approximately 80 million metric tons...
barriers have been developed for short-term applications where portability is important. These plastic barriers are normally filled with water after placement on-site to provide a moderate level of crash protection. They are not designed to deflect vehicles; vehicles may penetrate the barriers. These barriers can also be filled with soil, spill or cement to produce a heavier barrier with greater crash protection, at the cost of reduced portability.
See also
- Constant slope barrier
A constant slope barrier is a traffic barrier made of reinforced concrete and designed with a single slope that is used to separate lanes of vehicular traffic...
- F-shape barrier
The F-shape barrier is a concrete crash barrier, originally designed to divide lanes of traffic on a highway. It is a modification of the widely-used Jersey barrier design, and is generally considered safer....
- Barrier transfer machine
Barrier transfer machines, also known as zipper machines, are heavy vehicles used to transfer Jersey barriers or other concrete lane dividers used to relieve traffic congestion during rush hours....
- Cable barrier
Cable barrier, sometimes referred to as guard cable, is a type of roadside or median barrier. It consists of steel wire ropes mounted on weak posts. As is the case with any roadside barrier, its primary purpose is to prevent a vehicle from leaving the traveled way and striking a fixed object or...
- Median strip
On divided roads, such as divided highways or freeways/motorways, the central reservation , median, parkway , median strip or central nature strip is the area which separates opposing lanes of traffic...
- Crash barrier
External links