Freeway Nomenclature Construction Issues History Controversy

Freeways have high speed limits, multiple lanes for travel in each direction, and a large separation (either through distance or high crash barriers) between the lanes travelling in opposite directions. Crossroads are bypassed by grade (height) separation using underpasses and overpasses, with freeway entrances and exits being limited in number and designed with special onramps and offramps so as to ensure that vehicles do not disrupt the main flow of traffic as they enter or leave the freeway. Where freeways cross, engineers provide interchanges with elaborate ramp systems that allow for smooth transitions between all through routes (as funds permit). In major cities, drivers are directed by large signs mounted on overhead gantries. Freeways do not usually have traffic lights, but expressways do, in places where this distinction is made.

To minimize accidents, access to freeways is usually limited to vehicles capable of consistently maintaining a high speed, like automobiles, trucks, motorcycles, vans, and busThis article is about the form of transport. See computer bus or electrical bus for the use of the term in computing and electronics respectively, or places like Bus, Pas-de-Calais and Bus-Saint-Remy. The Bus, established by Mayor Frank Fasi, is Honolulu'es. PedestrianA pedestrian is a person travelling on foot, whether walking or running. In modern times, the term mostly refers to someone walking on a road but this was not the case historically. Nowadays, roads often have a designated footpath attached especially fors, bicyclists, slow-moving vehicles, horseThis article discusses ungulate mammals. For other meanings of horse see Horse (disambiguation). The Horse Equus caballus is a large ungulate mammal, one of the seven modern species of the genus Equus''. It has long played an important role in transportats, horse-drawn vehicles, and anything else that might obstruct fast-moving vehicles are all prohibited.

1 Nomenclature

Freeway is the term used in most of the United StatesThe United States of America also referred to as the United States U. America ¹ or the States is a federal republic in central North America, stretching from the Atlantic in the east to the Pacific Ocean in the west. It shares land borders with Canada in and CanadaCanada historically the Dominion of Canada is the second-largest, and northernmost, country in the world. It is a decentralized federation of 10 provinces and 3 territories, governed as a constitutional monarchy, and formed in 1867 through an act of Confe, and all of AustraliaAustralia is the sixth-largest country in the world (geographically), the only one to occupy an entire continent, and the largest in the region of Australasia. Australia includes the island of Tasmania, which is an Australian State. Its neighbouring count; the United Kingdom and some Commonwealth countries prefer motorwayA motorway ( United Kingdom, Republic of Ireland, and some Commonwealth nations) is both a type of road and a classification. Motorways may also be regarded as highways, designed to carry a large volume of traffic where a normal road would not suffice or, the German-speaking world uses autobahn, and the French-speaking world uses autoroute. Italy uses autostrada , and China uses the term expressway, although it once used freeway.

The United States definition, as accepted by civil engineers, is that an expressway is any highway to which adjoining property owners do not have a legal right of access. A freeway is an expressway which is free-flowing; that is to say, there are no traffic conflicts on the main line of the highway which must be mediated by a traffic signal, stop signs, or related traffic controls. Another way to look at it is that an expressway is limited-access, and a freeway is controlled-access, but this distinction is not universally accepted. Many non-engineers misapprehend the "free" in "freeway" to mean that such a highway must be free of charge to use. In some states, like California, the vast majority of freeways are toll-free (except where they cross an occasional toll bridge), while other states like Illinois and Florida have toll plazas at every exit on certain expressways.

In the U.S., the terms expressway and freeway are legally defined by federal regulation and under the laws of most states according to civil engineering usage described above. However, the distinction between these two terms is not universal, and in several states which built freeways very early on (including Connecticut, Illinois, Massachusetts, New Jersey, New York, and Pennsylvania), the terms expressway and freeway have the same meaning, and usually expressway, an older usage, is preferred. (In New Jersey and Pennsylvania, newer roads are often officially styled freeways, where older roads retain the title "expressway".) In the rest of the country, freeway is the usual term; however, the distinction between freeways and expressways is not always as clear or well-understood as it is in California, which has many of both kinds of highway. Florida is an exception to these conventions, and the terms "expressway" and "freeway" have two separate and distinct meanings. In Florida, an "expressway" is defined as a limited-access toll road, while a "freeway" is any other limited- or controlled-access road which costs no money to travel on.

2 Construction issues

Freeways have been constructed both between urban centres and within them, making common the style of sprawling suburban development found near most modern cities. As well as reducing travel times, the ease of driving on them reduces accident rates, though the speeds involved also tend to increase the severity and death rate of the collisions (or crashes) that do still happen.

Because abutters do not have the right of access that they would on an ordinary public way, the authority undertaking construction of a freeway is frequently required to provide alternate means of access to those landowners. This is frequently accomplished, in areas lacking a dense surface street network, by construction of two uncontrolled roads parallel to and on either side of the freeway, known as frontage roads. These often are designed with one-way traffic flow, but not always. In Texas, where this pattern is perhaps at its zenith, such roads are frequently constructed in anticipation of a future freeway corridor, as many as ten years in advance, in order to influence development patterns on the adjoining land. Frontage roads are also often constructed in more densely-developed areas as a means to provide convenient direct access to and from the parallel freeway while minimizing the need for interchanges at every major cross street.

3 History

The concept of limited-access automobile highways dates back to the New York City area Parkway system, which began to be constructed in 1907– 1908. Designers elsewhere also researched these ideas, especially in Germany, where the Autobahn became the first national freeway system. On December 30, 1940 California opened its first freeway, the Arroyo Seco Parkway, now called the Pasadena Freeway, which connected Pasadena with Los Angeles. Today, many freeways in the United States belong to the extensive Interstate highway system (most of which was completed between 1960 and 1990). Almost all interstates are freeways, but the earlier United States highway system and the highway systems of U.S. states also have many sections that are limited-access (though these systems are mostly composed of uncontrolled roads). Only a handful of sections of the Interstate system are not freeways, such as I-81 as it crosses the American span of the 2-lane Thousand Islands Bridge.

4 Controversy

Freeways have been heavily criticized by environmentalists and preservationists for the noise, pollution, and economic shifts they bring. The route of a new freeway can make or break rural towns depending upon their proximity. And freeways do take up a lot of land. Some argue that freeway expansion is self-defeating, in that expansion will just generate more traffic. This is the debated induced demand hypothesis.

Pro-freeway advocates point out that properly designed and maintained freeways are aesthetically pleasing, convenient, and safe (in comparison to the uncontrolled roads they replace or supplement.) Freeways expand recreation, employment and education opportunities for individuals and open new markets to small businesses. And for many, uncongested freeways are fun to drive.

At present, freeway expansion has largely stalled in the United States, due to a multitude of factors that converged in the 1970s: higher due process requirements prior to taking of private property, increasing land values, increasing costs for construction materials, local opposition to new freeways in urban cores, the passage of the National Environmental Policy Act (which imposed the requirement that each new project must have an environmental impact statement or report), and falling gas tax revenues as a result of better fuel mileage and the tax revolt movement.

5 Recent developments

Outside the U.S., many countries continue to rapidly expand their freeway networks. Examples include: Australia, Canada, Chile, China, France, India, Israel, Mexico, and Taiwan.

Progress has been made in making U.S. freeways and expressways more efficient. Experiments include the addition of high-occupancy vehicle lanes (HOV lanes) to discourage driving solo, and building new roads with train tracks down the median (or overhead). California has been very innovative in squeezing HOVs into limited right-of-way (by elevating them), and in building special HOV-only ramps so that HOVs can switch freeways or exit the freeway without having to merge across regular traffic. Many states have added truck-only ramps or lanes on heavily congested routes, so that cars need not weave around slow-moving big rigs.

Intelligent transportation systems (ITS) are also increasingly used, with cameras to monitor and direct traffic, so that police, fire, ambulance, tow, or other assistance vehicles can be dispatched as soon as there is a problem, and to warn drivers via variable message signs, radio, television. and the web to avoid problem areas. Research has been underway for many years on how to partly automate cars by making smart road s with such things as buried magnets to guide sensor-equipped vehicles, with on-board GPS to determine location, direction, and destination. While these systems may eventually be used on surface streets as well, they are most practical in a freeway setting.

In the United States, a few short privatized toll freeways have also been built by private companies with mixed success.

6 See also

7 External links

Georgia NaviGAtor - example of a freeway information system
A new concept in motorway design - Rethink the highways

Road transport

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