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Yangtze River Power Line Crossings
The Yangtze River power line crossings are overhead power lines that cross the Yangtze River in China. There are at least three power line crossings on the Yangtze River at Jiangyin, Nanjing, and Wuhu. The towers of the crossing in Jiangyin are among the highest in the world. Jiangyin One exists at Jiangyin, Jiangsu Province, China. Each pylon is situated at and at . It is a section of the 500 kV power line from the Yancheng power station to the Dou Shan substation in the province of Jiangsu. The power line section running over the river has a span width of . It is carried by two tall suspension towers, each weighing 4,192 tonnes. (for comparison, the towers even surpass the height of the Eiffel Tower, which is , including antenna). They are identical lattice towers of square cross section with an area of × 68 m at the base and × 8 m at the top. The pylons carry four conductors on the lower crossarm, above ground, with a length of and two conductors on the upper cro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overhead Line Crossing
An overhead line crossing is the crossing of an obstacle—such as a traffic route, a river, a valley or a strait—by an overhead power line. The style of crossing depends on the local conditions and regulations at the time the power line is constructed. Overhead line crossings can sometimes require extensive construction and can also have operational issues. In such cases, those in charge of construction should consider whether a crossing of the obstacle would be better accomplished by an underground or submarine cable. Crossings of roads and railway lines Overhead line crossings of roads, railway lines, and small- and medium-sized watercourses do not normally require special construction. However, in the first years building overhead line when crossing a railway line or a road, a scaffold under the line was required. Later in Germany and some other countries on each end of a powerline crossing of a state-operated railway, a dead-end tower was required, which can still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crossarm (utility Pole)
A utility pole, commonly referred to as a transmission pole, telephone pole, telecommunication pole, power pole, hydro pole, telegraph pole, or telegraph post, is a column or post used to support overhead power lines and various other public utilities, such as electrical cable, fiber optic cable, and related equipment such as transformers and street lights while depending on its application. They are used for two different types of power lines: ''sub transmission lines'', which carry higher voltage power between substations, and ''distribution lines'', which distribute lower voltage power to customers. Electrical wires and cables are routed overhead on utility poles as an inexpensive way to keep them insulated from the ground and out of the way of people and vehicles. Utility poles are usually made out of wood, aluminum alloy, metal, concrete, or composites like fiberglass. A Stobie pole is a multi-purpose pole made of two steel joists held apart by a slab of concrete in the midd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SkyscraperPage
SkyscraperPage is a website for skyscraper hobbyists and enthusiasts that tracks existing and proposed skyscrapers around the world. The site is owned by Skyscraper Source Media, a supplier of skyscraper diagrams for the publication, marketing, and display industries, and is a publisher of illustrated skyscraper diagram poster products. They are based in Victoria, British Columbia. The site has over 80,000 drawings of skyscrapers, other major macro-engineering projects, and tall structures around the world. The scale of the drawings are one pixel per meter. The images are created using pixel art. Using these diagrams, skyscrapers and other tall structures can be compared. General information is also given about each structure if available, such as the location, the year built, the height and the number of floors. The site also hosts a discussion forum for skyscraper enthusiasts. See also * SkyscraperCity * Emporis * List of Internet forums * List of tallest buildings in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Tallest Freestanding Steel Structures
This is a list of tallest freestanding steel structures in the world past and present. To be a freestanding steel structure it must not be supported by guy wires, the list therefore does not include guyed masts and the main vertical and lateral structural elements and floor systems in the case of buildings, are constructed from steel. This type of construction is a rarity today as most tall buildings are built with a composite structure featuring a reinforced concrete core. Oil platforms built using rigid steel jackets, such as the Bullwinkle (oil platform), are included and ranked as the local medium(water) does not provide any horizontal support. In fact they are over engineered specifically to resist water forces them rather than modulate them as compliant towers are designed to do. Demolished structures and structures under construction are also included but not ranked. Steel Structures (above 275 m / 900 ft in height) indicates a structures no longer standing. indicates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Tallest Freestanding Structures In The World
The tallest structure in the world is the Burj Khalifa skyscraper at . Listed are guyed masts (such as telecommunication masts), self-supporting towers (such as the CN Tower), skyscrapers (such as the Willis Tower), oil platforms, electricity transmission towers, and bridge support towers. This list is organized by absolute height. See History of the world's tallest structures, Tallest structures by category, and List of tallest buildings for additional information about these types of structures. Terminology Terminological and listing criteria follow Council on Tall Buildings and Urban Habitat definitions. Guyed masts are differentiated from towers – the latter not featuring any guy wires or other support structures; and buildings are differentiated from towers – the former having at least 50% of occupiable floor space although both are self-supporting structures. Lists by height This list includes structures of all types over 350 meters (1148 feet). Plus it includes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Tallest Buildings And Structures In The World
This is the History of the world's tallest structures. Overall Below is a list of the tallest structures supported by land. For most of the period from around 2650 BC to 1240 AD, the Egyptian pyramids (culminating in the Great Pyramid of Giza) were the tallest structures in the world. From 1240-1884 the records were held by European churches, and from 1954-2008 they were held by Guyed mast, guyed radio or TV masts. Since 2008, a skyscraper in Dubai called the Burj Khalifa has been the tallest structure supported by land, at 829.8 metres (2,722 feet). Although oil platforms supported by the sea have been the taller since Oil platform#History of deepest offshore oil wells, about 1980, with Oil platform#Particularly large examples, some examples up to 2,934 metres (9,627 feet). And some countries monitor their borders with Tethered balloon, tethered aerostats which can rise to 6,096 metres (20,000 feet). The Kanishka Stupa near Peshawar, Pakistan was built c. 151 and re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yangtze River Bridges And Tunnels
The bridges and tunnels across the Yangtze River carry rail and road traffic across China's longest and largest List of rivers of China, river and form a vital part of the Transport in China, country's transportation infrastructure. The river bisects China proper from west to east, and every major north–south bound China National Highways, highway and List of railway lines in China, railway must cross the Yangtze. Large urban centers along the river such as Chongqing, Wuhan, and Nanjing also have Urban rail transit in China, urban mass transit rail lines crossing the Yangtze. Pontoon bridges have been used by militaries for two thousand years on the Yangtze, but until the completion of the Wuhan Yangtze River Bridge in 1957, there were no permanent bridges along the main stretch of the river known as ''Chang Jiang'' (the "Yangtze River#Names, Long River"), from Yibin to the river mouth in Shanghai, a distance of . Since then, over 75 bridges and six tunnels have been built ov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anhui
Anhui is an inland Provinces of China, province located in East China. Its provincial capital and largest city is Hefei. The province is located across the basins of the Yangtze and Huai rivers, bordering Jiangsu and Zhejiang to the east, Jiangxi to the south, Hubei and Henan to the west, and Shandong to the north. With a population of 61 million, Anhui is the 9th most populous province in China. It is the 22nd largest Chinese province based on area, and the 12th most densely populated region of all 34 Chinese provincial regions. Anhui's population is mostly composed of Han Chinese. Languages spoken within the province include Lower Yangtze Mandarin, Wu Chinese, Wu, Huizhou Chinese, Hui, Gan Chinese, Gan and small portion of Central Plains Mandarin. The name "Anhui" derives from the names of two cities: Anqing and Huizhou, Anhui, Huizhou (now Huangshan City). The abbreviation for Anhui is , corresponding to the historical , and is also used to refer to the Wan River and Mount Ti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wuhu City
Wuhu () is a prefecture-level city in southeastern Anhui province of China, province, China. Sitting on the southeast bank of the Yangtze River, Wuhu borders Xuancheng to the southeast, Chizhou and Tongling to the southwest, Hefei City to the northwest, Ma'anshan city to the northeast, Jiangsu to the east, and is approximately southwest of Nanjing. With the urbanization trend in the southern part of Nanjing, a conurbation between Nanjing, Maanshan and Wuhu is in building with more than 10,660,000 inhabitants. History Wuhu is known to have been inhabited since at least 570 BCE. Present-day Wuhu evolved out of a settlement known as Jiuzi (), located on the southern bank of the Shuiyang River, about southeast of Wuhu's contemporary City centre, urban core. Jiuzi was a site of conflict prior to 670 BCE between the Chu (state), Chu and the Wu (state), Wu during the Spring and Autumn period. In 473 BCE, the Yue (state), Yue took Jiuzi from the Wu. In 306 BCE, the Chu took Jiuzi fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HVDC Three Gorges-Changzhou
A high-voltage direct current (HVDC) electric power transmission system uses direct current (DC) for electric power transmission, in contrast with the more common alternating current (AC) transmission systems. Most HVDC links use voltages between 100 kV and 800 kV. HVDC lines are commonly used for long-distance power transmission, since they require fewer conductors and incur less power loss than equivalent AC lines. HVDC also allows power transmission between AC transmission systems that are not synchronized. Since the power flow through an HVDC link can be controlled independently of the phase angle between source and load, it can stabilize a network against disturbances due to rapid changes in power. HVDC also allows the transfer of power between grid systems running at different frequencies, such as 50 and 60 Hz. This improves the stability and economy of each grid, by allowing the exchange of power between previously incompatible networks. The modern form o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dead-end Tower
A dead-end tower (also anchor tower, anchor pylon) is a fully self-supporting structure used in construction of overhead power lines. A dead-end transmission tower uses horizontal strain insulators at the end of conductors. Dead-end towers may be used at a substation as a transition to a "slack span" entering the equipment, when the circuit changes to a buried cable, when a transmission line changes direction by more than a few degrees, or at intervals along a straight run to limit the extent of a catastrophic collapse. Since dead-end towers require more material and are heavier and costlier than suspension towers, it is uneconomic to build a line with only self-supporting structures.D.G. Fink, H.W. Beaty, ''Standard Handbook for Electrical Engineers Eleventh Edition'', McGraw-Hill, 1978 , pp. 14-80, 14-81 Dead-end towers are used at regular intervals in a long transmission line to limit the cascading tower failures that might occur after a conductor failure. An in-line dead ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
