TYPES OF ROADS

There are many different types of roads, from multilane freeways and expressways to two-way country roads. One important quality of a road is known as control of access. This term describes how vehicles are allowed to enter and exit a road. By controlling access to a road, the road can support more traffic at higher speeds. Roads can be classified into three broad categories: highways, urban or city streets, and rural roads. Each type of road controls access to different degrees. Each type also differs in location, the amount of traffic it can safely handle, and the speed at which traffic can safely travel.

Highways are high-speed roads designed to connect major cities. There are many different types of highways. Highways differ in the amount of access control they have and in the amount of traffic they are designed to carry.

Highways with fully controlled access can handle the most traffic and are built to the highest construction standards. Freeways and expressways are examples of fully controlled access highways. Vehicles that enter and exit these types of highways can do it only at certain points along the highway, generally by using special entrance and exit ramps. The ramps allow vehicles to access the road without disturbing the flow of traffic. Intersections with other roads are avoided by using either bridges known as overpasses to carry one roadway over another or short tunnel-like structures called underpasses to carry one roadway under another. Shoulders on the edges of highways allow drivers of disabled vehicles to make repairs or await assistance without blocking traffic. Highways with fully controlled access generally have two or more lanes for each direction of travel and often include medians (dividers in the middle of the road) to separate traffic moving in opposite directions.

Some highways offer only partial control of access. These highways handle less traffic than highways with fully controlled access. They may intersect other roads at the same level (called at-grade) rather than using overpasses or underpasses. One benefit of highways with partially controlled access is that they are much cheaper to construct than highways with fully controlled access. Many highways in the USA are roads with partially controlled access.

Urban streets, which cover cities, towns, and most suburbs, allow vehicles to access properties such as homes and businesses. Urban streets are used by private motor vehicles, public transportation, bicycle traffic, and pedestrians. Urban streets also accommodate underground public-utility facilities, such as electrical wiring, water and sewage pipes, and telecommunications lines. In addition, these streets must often be built around existing buildings and other barriers, such as parks and rivers. Rather than shoulders, urban streets usually have raised edges called curbs, which provide a barrier between the street and the sidewalk.    

Urban streets are generally two-way paved roads that intersect each other frequently, allowing a high degree of access but at slow speeds. Traffic lights and signs help regulate the movement of vehicles along these streets and control the access to some streets.

Most urban streets are used to get quickly from one point to another and can accommodate high volumes of traffic. In large cities they are often similar to highways in construction even though they are located within city limits.

Rural roads are found in areas of the country outside cities, towns, and suburbs. Rural roads are classified into local and arterial roads. Because of the light traffic and extensive mileage on these roads, design standards are relatively low. Rural roads may or may not have shoulders. Local rural roads provide access to individual properties and farms. In many areas rural roads may be unpaved gravel roads. Two travel lanes, one for each direction of travel, can accommodate normal traffic on local rural arterial roads provide a high-speed network for heavier traffic between major towns in rural areas. They range from two-lane roadways to multilane highways. These roadways are designed to carry more traffic than local roads and are usually constructed to higher standards. Rural arterial roads often have shoulders and may have more than one lane in each direction.

Ex.2 Answer the questions.

1. What are the main types of roads?

2. What is the most important function of a road?

3. When can a road support more traffic at higher speeds?

4. What is the purpose of highways?

5. What categories can roads be classified into?

6. What can highways with fully controlled access handle?

7.  What allows vehicles to access the road without disturbing the flow of traffic?

8. What are the functions of intersections and shoulders?

9. What does partial control of access include?

10. What kind of benefit do highways with partially controlled access have?

11. What do urban streets accommodate?

12. How are rural roads classified?

13. What do rural roads provide?

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