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Cut (earthmoving)
In civil engineering, a cut or cutting is where soil or rock from a relative rise is removed. Cuts are typically used in road, rail, and canal construction to reduce a route's length and grade. Cut and fill construction uses the spoils from cuts to fill in defiles to create straight routes at steady grades cost-effectively. Cuts are used as alternatives to indirect routes, embankments, or viaducts. They also have the advantage of comparatively lower noise pollution than elevated or at-grade solutions. In river management, the term cut or cutting is also used, which refers to the action of short-cutting a meander, in order to speed a waterway's flow. History The term ''cutting'' appears in the 19th century literature to designate rock cuts developed to moderate grades of railway lines. ''Railway Age's Comprehensive Railroad Dictionary'' defines a cut as "a passage cut for the roadway through an obstacle of rock or dirt." Creation Cuts can be created by multiple pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Road Cut
In civil engineering, a cut or cutting is where soil or Rock (geology), rock from a relative rise is removed. Cuts are typically used in road, Rail transport, rail, and canal construction to reduce a route's length and Grade (slope), grade. Cut and fill construction uses the spoils from cuts to fill in defiles to create straight routes at steady grades cost-effectively. Cuts are used as alternatives to indirect routes, embankment (transportation), embankments, or viaducts. They also have the advantage of comparatively lower noise pollution than elevated or Intersection (road), at-grade solutions. In river management, the term Cut (river engineering), cut or cutting is also used, which refers to the action of short-cutting a meander, in order to speed a waterway's flow. History The term ''cutting'' appears in the 19th century literature to designate rock cuts developed to moderate grades of railway lines. ''Railway Age's Comprehensive Railroad Dictionary'' defines a cut as "a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Railway Cutting At The Summit Of Talerddig Bank - Geograph
Rail transport (also known as train transport) is a means of transport using wheeled vehicles running in tracks, which usually consist of two parallel steel rails. Rail transport is one of the two primary means of land transport, next to road transport. It is used for about 8% of passenger and freight transport globally, thanks to its energy efficiency and potentially high speed.Rolling stock on rails generally encounters lower frictional resistance than rubber-tyred road vehicles, allowing rail cars to be coupled into longer trains. Power is usually provided by diesel or electric locomotives. While railway transport is capital-intensive and less flexible than road transport, it can carry heavy loads of passengers and cargo with greater energy efficiency and safety. Precursors of railways driven by human or animal power have existed since antiquity, but modern rail transport began with the invention of the steam locomotive in the United Kingdom at the beginning of the 19th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gorge
A canyon (; archaic British English spelling: ''cañon''), gorge or chasm, is a deep cleft between escarpments or cliffs resulting from weathering and the erosion, erosive activity of a river over geologic time scales. Rivers have a natural tendency to cut through underlying surfaces, eventually wearing away rock layers as sediments are removed downstream. A river bed will gradually reach a baseline elevation, which is the same elevation as the body of water into which the river drains. The processes of weathering and erosion will form canyons when the river's River source, headwaters and estuary are at significantly different elevations, particularly through regions where softer rock layers are intermingled with harder layers more resistant to weathering. A canyon may also refer to a rift between two mountain peaks, such as those in ranges including the Rocky Mountains, the Alps, the Himalayas or the Andes. Usually, a river or stream carves out such splits between mountains. Exa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cliff
In geography and geology, a cliff or rock face is an area of Rock (geology), rock which has a general angle defined by the vertical, or nearly vertical. Cliffs are formed by the processes of weathering and erosion, with the effect of gravity. Cliffs are common on coasts, in mountainous areas, escarpments and along rivers. Cliffs are usually composed of rock that is resistant to weathering and erosion. The sedimentary rocks that are most likely to form cliffs include sandstone, limestone, chalk, and Dolomite (rock), dolomite. Igneous rocks such as granite and basalt also often form cliffs. An escarpment (or scarp) is a type of cliff formed by the movement of a geologic fault, a landslide, or sometimes by rock slides or falling rocks which change the differential erosion of the rock layers. Most cliffs have some form of scree slope at their base. In arid areas or under high cliffs, they are generally exposed jumbles of fallen rock. In areas of higher moisture, a soil slope may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Table
The water table is the upper surface of the phreatic zone or zone of saturation. The zone of saturation is where the pores and fractures of the ground are saturated with groundwater, which may be fresh, saline, or brackish, depending on the locality. It can also be simply explained as the depth below which the ground is saturated. The portion above the water table is the vadose zone. It may be visualized as the "surface" of the subsurface materials that are saturated with groundwater in a given vicinity. In coarse soils, the water table settles at the surface where the water Hydraulic head, pressure head is equal to the atmospheric pressure (where gauge pressure = 0). In soils where capillary action is strong, the water table is pulled upward, forming a capillary fringe. The groundwater may be from precipitation or from more distant groundwater flowing into the aquifer. In areas with sufficient precipitation, water infiltrates through pore spaces in the soil, passing through t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landslide
Landslides, also known as landslips, rockslips or rockslides, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, mudflows, shallow or deep-seated slope failures and debris flows. Landslides occur in a variety of environments, characterized by either steep or gentle slope gradients, from mountain ranges to coastal cliffs or even underwater, in which case they are called submarine landslides. Gravity is the primary driving force for a landslide to occur, but there are other factors affecting slope stability that produce specific conditions that make a slope prone to failure. In many cases, the landslide is triggered by a specific event (such as heavy rainfall, an earthquake, a slope cut to build a road, and many others), although this is not always identifiable. Landslides are frequently made worse by human development (such as urban sprawl) and resource exploitation (such as mining and deforestation). Land degradation freque ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral Extraction
Mining is the Resource extraction, extraction of valuable geological materials and minerals from the surface of the Earth. Mining is required to obtain most materials that cannot be grown through agriculture, agricultural processes, or feasibly created Chemical synthesis, artificially in a laboratory or factory. Ores recovered by mining include Metal#Extraction, metals, coal, oil shale, gemstones, limestone, chalk mining, chalk, dimension stone, rock salt, potash, gravel, and clay. The ore must be a rock or mineral that contains valuable constituent, can be extracted or mined and sold for profit. Mining in a wider sense includes extraction of any non-renewable resource such as petroleum, natural gas, or even fossil water, water. Modern mining processes involve prospecting for ore bodies, analysis of the profit potential of a proposed mine, extraction of the desired materials, and final mine reclamation, reclamation or restoration of the land after the mine is closed. Mining ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Open-pit Mining
Open-pit mining, also known as open-cast or open-cut mining and in larger contexts mega-mining, is a surface mining technique that extracts rock (geology), rock or minerals from the earth. Open-pit mines are used when deposits of commercially useful ore or rocks are found near the surface where the overburden is relatively thin. In contrast, deeper mineral deposits can be reached using underground mining. Open-pit mining is considered one of the most dangerous industrial sector, sectors in the industrial world. It causes significant effects to miners' health, as well as damage to the ecological land and water. Open-pit mining causes changes to vegetation, soil, and bedrock, which ultimately contributes to changes in surface hydrology, groundwater levels, and flow paths. Additionally, open-pit produces harmful pollutants depending on the type of mineral being mined, and the type of mining process being used. Extraction Miners typically drill a series of test holes to locate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daylighting (tunnels)
Daylighting a tunnel is to remove its "roof" of overlying rock and soil, exposing the railway or roadway to daylight and converting it to a railway or roadway Cut (earthmoving), cut. Tunnels are often daylighted to improve vertical or horizontal clearances—for example, to accommodate Double-stack rail transport, double-stack container trains or electrifying rail lines, where increasing the size of the tunnel bore is impractical. List of daylighted tunnels * Australia ** The Moocomonga Tunnel carried the Central Western railway line, Queensland, Central Western railway line through the Gogango Range in Queensland, Australia (). It opened in 1876. The tunnel was daylighted in 1983 due to rock falls which blocked the tunnel from time to time. ** The Coromandel and Pinera Tunnel, Pinera Tunnels on the Belair line in Adelaide, South Australia, both built as a single track tunnel with the line in 1883, were daylighted in the 1920s when the line to Belair, South Australia, Belair wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rock Blasting
Drilling and blasting is the controlled use of explosives and other methods, such as gas pressure blasting pyrotechnics, to break rock for excavation. It is practiced most often in mining, quarrying and civil engineering such as dam, tunnel or road construction. The result of rock blasting is often known as a rock cut. Drilling and blasting currently utilizes many different varieties of explosives with different compositions and performance properties. Higher velocity explosives are used for relatively hard rock in order to shatter and break the rock, while low velocity explosives are used in soft rocks to generate more gas pressure and a greater heaving effect. For instance, an early 20th-century blasting manual compared the effects of black powder to that of a wedge, and dynamite to that of a hammer. The most commonly used explosives in mining today are ANFO based blends due to lower cost than dynamite. Before the advent of tunnel boring machines (TBMs), drilling and b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Excavator
Excavators are heavy equipment (construction), heavy construction equipment primarily consisting of a backhoe, boom, dipper (or stick), Bucket (machine part), bucket, and cab on a rotating platform known as the "house". The modern excavator's house sits atop an undercarriage with Caterpillar track, tracks or wheels, being an evolution of the steam shovel (which itself evolved into the power shovel when steam was replaced by diesel and electric power). All excavation-related movement and functions of a hydraulic excavator are accomplished through the use of hydraulic fluid, with hydraulic cylinders and hydraulic motors, which replaced winches, chains, and steel ropes. Another principle change was the direction of the digging action, with modern excavators pulling their buckets toward them like a dragline rather than pushing them away to fill them the way the first powered shovels did. Terminology Excavators are also called diggers, scoopers, mechanical shovels, or 360-degree ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheel Tractor-scraper
In civil engineering, a wheel tractor-scraper (also known as a land scraper, land leveler, tournapull or simply called a scraper) is a type of heavy equipment used for earthmoving. It has a pan/hopper for loading and carrying material. The pan has a tapered horizontal front cutting edge that cuts into the soil like a carpenter's plane or cheese slicer and fills the hopper which has a movable ejection system. The horsepower of the machine, depth of the cut, type of material, and slope of the cut area affect how quickly the pan is filled. When full, the pan is raised, the apron is closed, and the scraper transports its load to the fill area. There the pan height is set and the lip is opened (the lip is what the bottom edge of the apron is called), so that the ejection system can be engaged for dumping the load. The forward momentum or speed of the machine affects how big an area is covered with the load. A high pan height and slow speed will dump the load over a short dista ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
