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Unpaved
A road surface (British English), or pavement (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 In the past, gravel road surfaces, hoggin, cobblestone and granite setts were extensively used, but these have mostly been replaced by asphalt or concrete laid on a compacted base course.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, 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. Pavements are crucial to countries such as United States and Canada, which heavily depend on road transpo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravel Road
A gravel road is a type of unpaved road surfaced with gravel that has been brought to the site from a quarry or stream bed. They are common in less-developed nations, and also in the rural areas of developed nations such as Canada and the United States. In New Zealand, and other Commonwealth countries, they may be known as metal roads. They may be referred to as "dirt roads" in common speech, but that term is used more for unimproved roads with no surface material added. If well constructed and maintained, a gravel road is an all-weather road. Characteristics Construction Compared to sealed roads, which require large machinery to work and pour concrete or to lay and smooth a bitumen-based surface, gravel roads are easy and cheap to build. However, compared to dirt roads, all-weather gravel highways are quite expensive to build, as they require front loaders, dump trucks, graders, and roadrollers to provide a base course of compacted earth or other material, sometimes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permeable Paving
Permeable paving surfaces are made of either a porous material that enables stormwater to flow through it or nonporous blocks spaced so that water can flow between the gaps. Permeable paving can also include a variety of surfacing techniques for roads, parking lots, and pedestrian walkways. Permeable pavement surfaces may be composed of; pervious concrete, porous asphalt, paving stones, or interlocking pavers. Unlike traditional impervious paving materials such as concrete and asphalt, permeable paving systems allow stormwater to percolate and infiltrate through the pavement and into the aggregate layers and/or soil below. In addition to reducing surface runoff, permeable paving systems can trap suspended solids, thereby filtering pollutants from stormwater. Permeable pavement is commonly used on roads, paths and parking lots subject to light vehicular traffic, such as cycle-paths, service or emergency access lanes, road and airport shoulders, and residential sidewalks and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asphalt
Asphalt, also known as bitumen (, ), is a sticky, black, highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term asphaltum was also used. Full text at Internet Archive (archive.org) The word is derived from the Ancient Greek ἄσφαλτος ''ásphaltos''. The largest natural deposit of asphalt in the world, estimated to contain 10 million tons, is the Pitch Lake located in La Brea in southwest Trinidad ( Antilles island located on the northeastern coast of Venezuela), within the Siparia Regional Corporation. The primary use (70%) of asphalt is in road construction, where it is used as the glue or binder mixed with aggregate particles to create asphalt concrete. Its other main uses are for bituminous waterproofing products, including production of roofing felt and for sealing flat roofs. In material sciences and engineering, the terms "asphal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by total area. Its southern and western border with the United States, stretching , is the world's longest binational land border. Canada's capital is Ottawa, and its three largest metropolitan areas are Toronto, Montreal, and Vancouver. Indigenous peoples have continuously inhabited what is now Canada for thousands of years. Beginning in the 16th century, British and French expeditions explored and later settled along the Atlantic coast. As a consequence of various armed conflicts, France ceded nearly all of its colonies in North America in 1763. In 1867, with the union of three British North American colonies through Confederation, Canada was formed as a federal dominion of four provinces. This began an accretion of provinces an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greece
Greece,, or , romanized: ', officially the Hellenic Republic, is a country in Southeast Europe. It is situated on the southern tip of the Balkans, and is located at the crossroads of Europe, Asia, and Africa. Greece shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to the northeast. The Aegean Sea lies to the east of the mainland, the Ionian Sea to the west, and the Sea of Crete and the Mediterranean Sea to the south. Greece has the longest coastline on the Mediterranean Basin, featuring thousands of islands. The country consists of nine traditional geographic regions, and has a population of approximately 10.4 million. Athens is the nation's capital and largest city, followed by Thessaloniki and Patras. Greece is considered the cradle of Western civilization, being the birthplace of democracy, Western philosophy, Western literature, historiography, political science, major scientific and mathematica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metallurgy
Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the science and the technology of metals; that is, the way in which science is applied to the production of metals, and the engineering of metal components used in products for both consumers and manufacturers. Metallurgy is distinct from the craft of metalworking. Metalworking relies on metallurgy in a similar manner to how medicine relies on medical science for technical advancement. A specialist practitioner of metallurgy is known as a metallurgist. The science of metallurgy is further subdivided into two broad categories: chemical metallurgy and physical metallurgy. Chemical metallurgy is chiefly concerned with the reduction and oxidation of metals, and the chemical performance of metals. Subjects of study in chemical metallurgy include m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian Subcontinent
The Indian subcontinent is a list of the physiographic regions of the world, physiographical region in United Nations geoscheme for Asia#Southern Asia, Southern Asia. It is situated on the Indian Plate, projecting southwards into the Indian Ocean from the Himalayas. Geopolitically, it includes the countries of Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka."Indian subcontinent". ''Oxford Dictionary of English, New Oxford Dictionary of English'' () New York: Oxford University Press, 2001; p. 929: "the part of Asia south of the Himalayas which forms a peninsula extending into the Indian Ocean, between the Arabian Sea and the Bay of Bengal. Historically forming the whole territory of Greater India, the region is now divided into three countries named Bangladesh, India and Pakistan." The terms ''Indian subcontinent'' and ''South Asia'' are often used interchangeably to denote the region, although the geopolitical term of South Asia frequently includes Afghanist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indus Valley Civilization
The Indus Valley Civilisation (IVC), also known as the Indus Civilisation was a Bronze Age civilisation in the northwestern regions of South Asia, lasting from 3300 BCE to 1300 BCE, and in its mature form 2600 BCE to 1900 BCE. Together with ancient Egypt and Mesopotamia, it was one of three early civilisations of the Near East and South Asia, and of the three, the most widespread. Its sites spanned an area from much of Pakistan, to northeast Afghanistan, and northwestern India. The civilisation flourished both in the alluvial plain of the Indus River, which flows through the length of Pakistan, and along a system of perennial monsoon-fed rivers that once coursed in the vicinity of the Ghaggar-Hakra, a seasonal river in northwest India and eastern Pakistan. The term ''Harappan'' is sometimes applied to the Indus civilisation after its type site Harappa, the first to be excavated early in the 20th century in what was then the Punjab province of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
England
England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe by the North Sea to the east and the English Channel to the south. The country covers five-eighths of the island of Great Britain, which lies in the North Atlantic, and includes over 100 smaller islands, such as the Isles of Scilly and the Isle of Wight. The area now called England was first inhabited by modern humans during the Upper Paleolithic period, but takes its name from the Angles, a Germanic tribe deriving its name from the Anglia peninsula, who settled during the 5th and 6th centuries. England became a unified state in the 10th century and has had a significant cultural and legal impact on the wider world since the Age of Discovery, which began during the 15th century. The English language, the Anglican Church, and Engli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glastonbury
Glastonbury (, ) is a town and civil parish in Somerset, England, situated at a dry point on the low-lying Somerset Levels, south of Bristol. The town, which is in the Mendip district, had a population of 8,932 in the 2011 census. Glastonbury is less than across the River Brue from Street, which is now larger than Glastonbury. Evidence from timber trackways such as the Sweet Track show that the town has been inhabited since Neolithic times. Glastonbury Lake Village was an Iron Age village, close to the old course of the River Brue and Sharpham Park approximately west of Glastonbury, that dates back to the Bronze Age. Centwine was the first Saxon patron of Glastonbury Abbey, which dominated the town for the next 700 years. One of the most important abbeys in England, it was the site of Edmund Ironside's coronation as King of England in 1016. Many of the oldest surviving buildings in the town, including the Tribunal, George Hotel and Pilgrims' Inn and the Somerset R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corduroy Road
A corduroy road or log road is a type of road or timber trackway made by placing logs, perpendicular to the direction of the road over a low or swampy area. The result is an improvement over impassable mud or dirt roads, yet rough in the best of conditions and a hazard to horses due to shifting loose logs. Corduroy roads can also be built as a foundation for other surfacing. If the logs are buried in wet, acidic, anaerobic soils such as peat or muskeg, they decay very slowly. A few corduroy road foundations that date back to the early 20th century still exist in North America. One example is the Alaska Highway between Burwash Landing and Koidern, Yukon, Canada, which was rebuilt in 1943, less than a year after the original route was graded on thin soil and vegetation over permafrost, by using corduroy, then building a gravel road on top. During the 1980s, the gravel was covered with a chip-seal. The late 1990s saw replacement of this road with modern road construction, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pavement Layers
Pavement may refer to: * Pavement (architecture), an outdoor floor or superficial surface covering * Road surface, the durable surfacing of roads and walkways ** Asphalt concrete, a common form of road surface * Sidewalk or pavement, a walkway along the side of a road * Cool pavement, is pavement that delivers higher solar reflectance than conventional dark pavement. * Pavement (York), a street in York, in England Geology * Limestone pavement, a naturally occurring landform that resembles an artificial pavement * Desert pavement, a desert ground surface covered with closely packed rock fragments of pebble and cobble size * Tessellated pavement, a rare sedimentary rock formation that occurs on some ocean shores * Glacial striation Glacial striations or striae are scratches or gouges cut into bedrock by glacial abrasion. These scratches and gouges were first recognized as the result of a moving glacier in the late 18th century when Swiss alpinists first associated them w ... ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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