Gravel road is a type of unpaved road that appears with gravel that has been taken to the site from a quarry or stream. They are common in less developed countries, as well as in rural areas of developed countries such as Canada and the United States. In New Zealand, and other Commonwealth countries, they may be known as ' metal roads' . They can be referred to as 'dirt roads' in public speaking, but the term is used more for bad roads without added surface material. If well built and maintained, gravel roads are all-weather roads.
Video Gravel road
Characteristics
Construction
Compared to closed roads, which require large machines to work and pour concrete or to lay and smooth asphalt-based surfaces, gravel roads are easy and inexpensive to build. However, compared to dirt roads, all-weather highway gravel is quite expensive to build, as they require front loaders, dump trucks, graders, and roadrollers to provide a compacted earth base course or other material, sometimes macadamised, covered with one or gravel layer which is more different. Graders are also used to produce more extreme camber than paved roads to aid drainage, as well as to build ditches and drainage embankments in lowland areas. Cell confinement systems can be used to prevent the washboarding effect.
Materials
The pebbles used consist of various amounts of crushed stone, sand, and fines . Fines are mud or clay particles smaller than 0.075 millimeters (0.0030 in), which can act as a binder. The crushed stone is used because the pebble with a cracked face will remain in a better place than the round river gravel. Gravel is good for gravel roads will have a higher percentage of gravel than gravel used as a subbase for paved roads. This often creates problems if gravel roads are paved without adding sandstone and pebbles to melt a percentage of fines.
The gravel road is very different from the 'gravel drive', which is popular as a private entrance in the UK. It uses clean pebbles consisting of uniforms, cobblestones and small pebbles.
Lateral and murram road
In Africa and parts of Asia and South America, laterite soils are used to build dirt roads. Yet laterite, called murram in East Africa, varies in the proportion of stones (usually very small) to earth and sand. Starting from the hard pebbles to the softer earth that is embedded with small stones. Not all laterite and murram roads are strictly gravel roads. Laterite and murram containing significant proportions of clay become very slippery when wet, and in the rainy season, it may be difficult even for a four-wheeled vehicle to avoid slipping off a very sloping path to a roadside drainage channel. As it dries, such laterites can become very hard, like a sun-dried brick.
Maintenance
Gravel roads require much more frequent maintenance than paved roads, especially after wet periods and when accommodating increased traffic. Move the wheel pushing the material out (as well as between the travel paths), leading to rutting, reducing water runoff, and ultimately destruction of the road if unchecked. As long as the process is interrupted early enough, simple rearrangement is sufficient, with material being pushed back into shape.
The gravel road segment on the ground is also easy to be easy due to running water. When assessing or building roads, waterbars are used to direct water from the road. As an alternative method, bumps can be formed in gravel along the road to block the flow of water, thereby reducing rutting.
Another problem with gravel roads is washboarding - the formation of wrinkles all over the surface at right angles to the direction of travel. They can become severe enough to cause vibrations in the vehicle so that the bolts loosen or crack in component form. Grading removes wrinkles, and reconstruction with good quality gravel options can help prevent it from undergoing change. In addition, installing a cellular confinement system will prevent wrinkles like washers from occurring.
Gravel roads are often found in cold climates because they are less susceptible to freezing/liquefying damage than asphalt roads. Inferior gravel surfaces do not matter if the road is covered by snow and ice for a long time.
Driving
Although a well-constructed and graded gravel road is suitable for speeds of up to 100 km/h (60 mph), driving on it requires more attention to surface variations and is easier to lose control than on paved roads. In addition to holes, loose wheels and loose stones or sandy backs on the edges or in the middle of the road, problems associated with driving on rocky roads include:
- sharper and bigger stones cut and punctured the tires, or thrown by the wheel and damaged the bottom, especially piercing the unmodified car fuel tank
- rocks jumping around hitting the car body, lights, or windshields as two vehicles drive at high speed
- dust removed from passing vehicles reduces visibility
- 'washboard' corrugations cause loss of control or damage to the vehicle due to excessive vibration. These are most commonly found near intersections as termination or braking causing them to form or otherwise if heavy farming or other equipment often uses this path.
- glide in the mud after rain
- the fishtailing vehicle as a result of the ruts on the surface of the gravel. Often found on frequent streets
- In areas with high rainfall, an increase in camber is needed to drain water, and open drainage channels on the road side, often causing vehicles with high center of gravity, such as trucks and off-road vehicles, to the upside if they do not close to the crown path
- Excess dust pierces the rubber mold that opens the door that destroys the seal
- Bindings lost in the form of road dust, if mixed with rain, will remove the painted surface of the vehicle
- Many gravel roads have only one lane that is wide or slightly larger, requiring special attention while driving at higher speeds
Maps Gravel road
Related types
Forest service road
A 'Forest Service Road' is a type of incomplete access road, built by the US Forest Service to access remote areas that have not yet been developed. These roads are built primarily for industrial logging and forest management workers, although in some cases are also used for inland recreational access.
The river road network is branched off from FSR trunks. Roads are usually named after regional districts, and branches have alphanumeric designations.
Typically, four-wheel drive vehicles with sufficiently high distances are required to travel effectively on the road, especially where large holes and/or waterbars are present. Switchback is used to make roads passable through steep terrain.
These streets quickly become damaged and quickly become impassable. The remains of old roads can exist for decades. They are finally erased by washout, erosion, and ecological succession.
Road logging
Logging roads are built to provide access to forests for logging and other forest management operations. They are usually narrow, winding, and unpaved, but the main haul road can be widened, straightened or paved if traffic volume guarantees it.
The standard choice of road design is a trade off between construction costs and freight costs (designed to reduce roads). Roads that only operate multiple stands will be used by relatively few trucks over their lifetime, making sense to save on construction costs with narrow, winding, unpaved roads that increase the time (and freight costs) of some of these trips. The main haul roads serve large areas but will be used by many trucks every day, and each trip will be shorter (saving time and money) if the road is more straight and wider, with a smoother surface.
Logging trucks are generally provided in the right way. In areas where this practice is set (or should be) a non-highway road with heavy logging traffic can be "controlled by radio", which means a CB radio on any vehicle on the road is recommended for safety reasons.
Picture gallery
See also
References
External links
- Skorseth, Ken; Selim, Ali A. (November 2000),
Gravel Maintenance and Design Guide (PDF) , FHWA, South Dakota Local Transport Assistance Program - Sensitive Environmental Maintenance Practices for U.S. Forest Transportation and Gravel Transport and Gravel.
Source of the article : Wikipedia
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