Formation Level
In transport engineering, subgrade is the native material underneath a constructed road,http://www.highwaysmaintenance.com/drainage.htm The Idiots' Guide to Highways Maintenance ''highwaysmaintenence.com'' Road surface, pavement or Track (rail transport), railway track (US: railroad track). It is also called formation level. The subgrade provides support to the subbase level and acts as an integral load-bearing layer. Failure of the subgrade can cause depressions and rutting of the upper base and surface courses. These in turn can lead to water pooling in deformations and cause vehicle aquaplaning among other issues. The term can also refer to imported material that has been used to build an Embankment (transportation), embankment. Construction Subgrades are commonly compacted before the construction of a road, pavement or railway track. This is to ensure their ability to absorb the loads being transferred down from the upper layers, increasing the life and wear of the surface ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Section Through Railway Track And Foundation
Section, Sectioning, or Sectioned may refer to: Arts, entertainment and media * Section (music), a complete, but not independent, musical idea * Section (typography), a subdivision, especially of a chapter, in books and documents ** Section sign (ยง), typographical characters * Section (bookbinding), a group of sheets, folded in the middle, bound into the binding together * The Section (band), a 1970s American instrumental rock band * The Outpost (1995 film), ''The Outpost'' (1995 film), also known as ''The Section'' * Section, an instrumental group within an orchestra#Organization, orchestra * "Section", a song by 2 Chainz from the 2016 album ''ColleGrove'' * Sectioning (Peep Show), "Sectioning" (''Peep Show''), a 2005 television episode * David "Section" Mason, a fictional character in ''Call of Duty: Black Ops II'' Organisations * Section (Alpine club) * Section (military unit) * Section (Scouting) Science, technology and mathematics Science * Section (archaeology), a vi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Transport Engineering
Transportation engineering or transport engineering is the application of technology and scientific principles to the planning, functional design, operation and management of facilities for any mode of transportation to provide for the safe, efficient, rapid, comfortable, convenient, economical, and environmentally compatible movement of people and goods transport. Theory The planning aspects of transportation engineering relate to elements of urban planning, and involve technical forecasting decisions and political factors. Technical forecasting of passenger travel usually involves an urban transportation planning model, requiring the estimation of trip generation, trip distribution, mode choice, and route assignment. More sophisticated forecasting can include other aspects of traveler decisions, including auto ownership, trip chaining (the decision to link individual trips together in a tour) and the choice of residential or business location (known as land use forec ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Road
A road is a thoroughfare used primarily for movement of traffic. Roads differ from streets, whose primary use is local access. They also differ from stroads, which combine the features of streets and roads. Most modern roads are paved. The words "road" and "street" are commonly considered to be interchangeable, but the distinction is important in urban design. There are many types of roads, including parkways, avenues, controlled-access highways (freeways, motorways, and expressways), tollways, interstates, highways, and local roads. The primary features of roads include lanes, sidewalks (pavement), roadways (carriageways), medians, shoulders, verges, bike paths (cycle paths), and shared-use paths. Definitions Historically, many roads were simply recognizable routes without any formal construction or some maintenance. The Organization for Economic Co-operation and Development (OECD) defines a road as "a line of communication (travelled way) using a stab ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Road Surface
A road surface (British English) or pavement (North American English) is the durable surface material laid down on an area intended to sustain vehicular or foot traffic, such as a road or walkway. In the past, gravel road surfaces, macadam, hoggin, cobblestone and granite setts were extensively used, but these have mostly been replaced by asphalt or concrete laid on a compacted base course. Asphalt mixtures have been used in pavement construction since the beginning of the 20th century and are of two types: metalled (hard-surfaced) and unmetalled roads. Metalled roadways are made to sustain vehicular load and so are usually made on frequently used roads. Unmetalled roads, also known as gravel roads or dirt roads, are rough and can sustain less weight. Road surfaces are frequently marked to guide traffic. Today, permeable paving methods are beginning to be used for low-impact roadways and walkways to prevent flooding. Pavements are crucial to countries such as United St ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Track (rail Transport)
Railway track ( and UIC terminology) or railroad track (), also known as permanent way () or "P way" ( and Indian English), is the structure on a railway or railroad consisting of the rails, fasteners, sleepers ( railroad ties in American English) and ballast (or slab track), plus the underlying subgrade. It enables trains to move by providing a dependable, low-friction surface on which steel wheels can roll. Early tracks were constructed with wooden or cast-iron rails, and wooden or stone sleepers. Since the 1870s, rails have almost universally been made from steel. Historical development The first railway in Britain was the Wollaton wagonway, built in 1603 between Wollaton and Strelley in Nottinghamshire. It used wooden rails and was the first of about 50 wooden-railed tramways built over the subsequent 164 years. These early wooden tramways typically used rails of oak or beech, attached to wooden sleepers with iron or wooden nails. Gravel or small stones were pa ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Aquaplaning
Aquaplaning or hydroplaning by the tires of a road vehicle, aircraft or other wheeled vehicle occurs when a layer of water builds between the wheels of the vehicle and the road surface, leading to a loss of traction that prevents the vehicle from responding to control inputs. If it occurs to all wheels simultaneously, the vehicle becomes, in effect, an uncontrolled sled. Aquaplaning is a different phenomenon from when water on the surface of the roadway merely acts as a lubricant. Traction is diminished on wet pavement even when aquaplaning is not occurring. Causes Every vehicle function that changes direction or speed relies on friction between the tires and the road surface. The grooves of a rubber tire are designed to disperse water from beneath the tire, providing high friction even in wet conditions. Aquaplaning occurs when a tire encounters more water than it can dissipate. Water pressure in front of the wheel forces a wedge of water under the leading edge of the tire, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Embankment (transportation)
An embankment is a raised wall, bank or mound made of earth or stones, that are used to hold back water or carry a roadway. A road, Rail tracks, railway line, or canal is normally raised onto an embankment made of compacted soil (typically clay or rock-based) to avoid a change in level required by the terrain, the alternatives being either to have an unacceptable change in level or detour to follow a contour. A cutting (transportation), cutting is used for the same purpose where the land is originally higher than required. Materials Embankments are often constructed using material obtained from a cutting. Embankments need to be constructed using non-aerated and waterproofed, compacted (or entirely non-porous) material to provide adequate support to the formation and a long-term level surface with stability. An example material for road embankment building is sand-bentonite mixture often used as a protective to protect underground utility cables and pipelines. Intersection of ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Subsoil
Subsoil is the layer of soil under the topsoil on the surface of the ground. Like topsoil, it is composed of a variable mixture of small particles such as sand, silt and clay, but with a much lower percentage of organic matter and humus. The subsoil is labeled the soil horizon, B Horizon in most soil mapping systems. Because it has less organic matter than topsoil, subsoil soil color, soil colour is mainly derived from iron oxides. Iron oxides and clay minerals form due to soil formation, weathering. Rainfall moves these weathering products downward as solutes and colloids by rainfall. The subsoil is the depth where these weathering products accumulate. The accumulation of clay minerals, iron, aluminum, and organic compounds is called illuviation. Whereas the topsoil tends to be the depth of greatest physical, chemical, and biological activity, the subsoil is the depth of most deposition. Due to physical, chemical, and biological activity, the subsoil generally has a soil struct ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Track Bed
The track bed or trackbed is the groundwork onto which a railway track is laid. Trackbeds of disused railways are sometimes used for recreational paths or new light rail links. Background According to Network Rail Network Rail Limited is the owner (via its subsidiary Network Rail Infrastructure Limited, which was known as Railtrack plc before 2002) and railway infrastructure manager, infrastructure manager of most of the railway network in Great Britain. ..., the trackbed is the layers of Track ballast, ballast and sub-ballast above a prepared subgrade/formation (see diagram). It is designed primarily to reduce the stress on the subgrade. Other definitions include the surface of the ballast on which the track is laid,, p. 386. the area left after a track has been dismantled and the ballast removed or the track formation beneath the ballast and above the natural ground. The trackbed can significantly influence the performance of the track, especially ride quality of passeng ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Road Transport
Road transport or road transportation is a type of transport using roads. Transport on roads can be roughly grouped into the transportation of goods and transportation of people. In many countries licensing requirements and safety regulations ensure a separation of the two industries. Movement along roads may be by Bicycle, bike, Car, automobile, bus, truck, or by Pack animal, animal such as horse or oxen. Standard networks of roads were adopted by Ancient Rome, Romans, Persians, Aztec, and other early empires, and may be regarded as a feature of empires. Cargo may be transported by Truck driver, trucking companies, while passengers may be transported via Public transport, mass transit. Commonly defined features of modern roads include defined lanes and Traffic sign, signage. Various classes of road exist, from two-lane local roads with at-grade Intersection (road), intersections to controlled-access highways with all cross traffic grade-separated. The nature of road transportat ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Pavements
Pavement(s) or paving may refer to: Surfacing * Road surface, the durable surfacing of roads and walkways * Sidewalk, a walkway along the side of a road, called a pavement in British English * Asphalt concrete, a common form of road surface * Cool pavement, pavement that delivers higher solar reflectance than conventional dark pavement * Crazy paving, a means of hard-surfacing used outdoors * Nicolson pavement, a road surface material consisting of wooden blocks * Pavers (flooring), an outdoor floor done in blocks * Permeable paving, paving that enables stormwater to flow through it or between gaps * Portuguese pavement, the traditional paving used in most pedestrian areas in Portugal * Resin-bound paving, a mixture of aggregate stones and resin used to pave footpaths, driveways, etc. * Tactile paving, textured ground surface indicators to assist vision-impaired pedestrians * Whitetopping, the covering of an existing asphalt pavement with a layer of Portland cement concret ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |