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Immersed Tubes
An immersed tube (or immersed tunnel) is a kind of undersea tunnel composed of segments, constructed elsewhere and floated to the tunnel site to be sunk into place and then linked together. They are commonly used for road and rail crossings of rivers, estuaries and sea channels/harbours. Immersed tubes are often used in conjunction with other forms of tunnel at their end, such as a cut and cover or bored tunnel, which is usually necessary to continue the tunnel from near the water's edge to the entrance (portal) at the land surface. Construction The tunnel is made up of separate elements, each prefabricated in a manageable length, then having the ends sealed with bulkheads so they can be floated. At the same time, the corresponding parts of the path of the tunnel are prepared, with a trench on the bottom of the channel being dredged and graded to fine tolerances to support the elements. The next stage is to place the elements into place, each towed to the final location, in m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Undersea Tunnel
An underwater tunnel is a tunnel which is partly or wholly constructed under the sea or a river. They are often used where building a bridge or operating a ferry link is unviable, or to provide competition or relief for existing bridges or ferry links.Sullivan, WalterProgress In Technology Revives Interest In Great Tunnels New York Times, June 24, 1986. Retrieved 15 August 2010. While short tunnels are often road tunnels which may admit motorized traffic, unmotorized traffic or both, concerns with ventilation lead to the longest tunnels (such as the Channel Tunnel or the Seikan Tunnel) being railway electrification systems, electrified rail tunnels. Types of tunnel Various methods are used to construct underwater tunnels, including an immersed tube and a submerged floating tunnel. The immersed tube method involves steel tube segments that are positioned in a trench in the sea floor and joined together. The trench is then covered and the water pumped from the tunnel. Submerged floa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oakland, California
Oakland is the largest city and the county seat of Alameda County, California, United States. A major West Coast of the United States, West Coast port, Oakland is the largest city in the East Bay region of the San Francisco Bay Area, the third largest city overall in the Bay Area and the List of largest California cities by population, eighth most populated city in California. With a population of 440,646 in 2020, it serves as the Bay Area's trade center and economic engine: the Port of Oakland is the busiest port in Northern California, and the fifth busiest in the United States of America. An act to municipal corporation, incorporate the city was passed on May 4, 1852, and incorporation was later approved on March 25, 1854. Oakland is a charter city. Oakland's territory covers what was once a mosaic of California coastal prairie, California coastal terrace prairie, oak woodland, and north coastal scrub. In the late 18th century, it became part of a large ''rancho'' grant in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zhongshan
Zhongshan (; ) is a prefecture-level city in the south of the Pearl River Delta in Guangdong province, China. As of the 2020 census, the whole city with 4,418,060 inhabitants is now part of the Guangzhou–Shenzhen conurbation with 65,565,622 inhabitants. The city-core subdistricts used to be called Shiqi or Shekki (). Zhongshan is one of the few Chinese cities to be named after a person. It was originally named Xiangshan (, "Fragrant Mountain"; Cantonese: ''Heung-saan''), but was renamed in 1925 in honor of Sun Yat-sen, who is known in China as "Sun Zhongshan". Sun was the founding father of the Republic of China who is also regarded positively by the People's Republic. He was born in Cuiheng village in Nanlang Township of what was then Xiangshan County. Names Until 1925, Zhongshan was generally known as Xiangshan or Heung-san (Siangshan) (), in reference to the many flowers that grew in the mountains nearby. The city was renamed in honor of Sun Yat-sen, who had adopted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shenzhen
Shenzhen (; ; ; ), also historically known as Sham Chun, is a major sub-provincial city and one of the special economic zones of China. The city is located on the east bank of the Pearl River estuary on the central coast of southern province of Guangdong, bordering Hong Kong to the south, Dongguan to the north, and Huizhou to the northeast. With a population of 17.56 million as of 2020, Shenzhen is the third most populous city by urban population in China after Shanghai and Beijing. Shenzhen is a global center in technology, research, manufacturing, business and economics, finance, tourism and transportation, and the Port of Shenzhen is the world's fourth busiest container port. Shenzhen is classified as a Large-Port Megacity, the largest type of port-city in the world. Shenzhen roughly follows the administrative boundaries of Bao'an County, which was established since imperial times. The southern portion of Bao'an County was seized by the British after the Opium Wars an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated between the Baltic and North seas to the north, and the Alps to the south; it covers an area of , with a population of almost 84 million within its 16 constituent states. Germany borders Denmark to the north, Poland and the Czech Republic to the east, Austria and Switzerland to the south, and France, Luxembourg, Belgium, and the Netherlands to the west. The nation's capital and most populous city is Berlin and its financial centre is Frankfurt; the largest urban area is the Ruhr. Various Germanic tribes have inhabited the northern parts of modern Germany since classical antiquity. A region named Germania was documented before AD 100. In 962, the Kingdom of Germany formed the bulk of the Holy Roman Empire. During the 16th ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denmark
) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Danish Realm, Kingdom of Denmark , established_title = History of Denmark#Middle ages, Consolidation , established_date = 8th century , established_title2 = Christianization , established_date2 = 965 , established_title3 = , established_date3 = 5 June 1849 , established_title4 = Faroese home rule , established_date4 = 24 March 1948 , established_title5 = European Economic Community, EEC 1973 enlargement of the European Communities, accession , established_date5 = 1 January 1973 , established_title6 = Greenlandic home rule , established_date6 = 1 May 1979 , official_languages = Danish language, Danish , languages_type = Regional languages , languages_sub = yes , languages = German language, GermanGerman is recognised as a protected minority language in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fehmarn Belt Fixed Link
The Fehmarn Belt fixed link ( da, Femern Bælt-forbindelsen, german: Fehmarnbelt-Querung) or Fehmarn Belt tunnel is an under-construction immersed tunnel, which will connect the Danish island of Lolland with the German island of Fehmarn, crossing the Fehmarn Belt in the Baltic Sea. It will provide a direct link between northern Germany and Lolland, and from there to the Danish island of Zealand and Copenhagen, becoming the ''world's longest road and rail tunnel.'' The tunnel will be a major connection between central Europe and Scandinavia. It will shorten the travel time between Lolland and Fehmarn from 45 minutes by ferry (excluding waiting and boarding time) to 10 minutes by car and seven minutes by train. The electrified high-speed rail line will be capable of reaching . The project had a first financial volume of €5.5 billion, €7.4 billion when the State Treaty of Denmark and Germany was adopted in 2010, and recently approximately €10 billion (2022). The tun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transbay Tube
The Transbay Tube is an underwater rail tunnel that carries Bay Area Rapid Transit's four transbay lines under San Francisco Bay between the cities of San Francisco and Oakland in California. The tube is long, and attaches to twin bored tunnels. The underground section of rail between the nearest stations (one of which is underground) totals in length. The tube has a maximum depth of below sea level. Built using the immersed tube technique, the Transbay tube was constructed on land in 57 sections, transported to the site, and then submerged and fastened to the bottom – primarily by packing its sides with sand and gravel. Opened in 1974, the tunnel was the final segment of the original BART system to open. All BART lines except the Berryessa-Richmond line operate through the Transbay Tube, making it one of the busiest sections of the system in terms of passenger and train traffic. During peak commute times, over 28,000 passengers per hour travel through the tunnel with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shenzhen–Zhongshan Bridge
The Shenzhen–Zhongshan Bridge is a bridge under construction. It will connect two major cities on the Pearl River Delta (PRD) in China: the city of Shenzhen on the eastern side of the PRD, and the city of Zhongshan on the western side. It will consist of a series of bridges and tunnels, starting from Bao'an International Airport on the Shenzhen side. The proposed 51 km eight-lane link is scheduled to be completed in 2024 and is expected to cost around US$4.83 billion.The Wall Street Journal"A Hong Kong Tale of 2 Bridges" 2 May 2013. Retrieved 25 July 2013. It will be located about 27 km downriver from the Humen Bridge, the only current bridge crossing of the estuary, and some 32 km north of the new Hong Kong–Zhuhai–Macau Bridge, which links the cities of Hong Kong, Zhuhai, and Macau at the southern end of the PRD. Construction started in May 2017 with an opening date in 2024. History Shenzhen lobbied hard in the early 2000s to be included in the Hong Kong– ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hong Kong–Zhuhai–Macau Bridge
The Hong Kong–Zhuhai–Macau Bridge (HZMB) is a bridge–tunnel system consisting of a series of three cable-stayed bridges, an undersea tunnel, and four artificial islands. It is both the longest sea crossing and the longest open-sea fixed link in the world. The HZMB spans the Lingding and Jiuzhou channels, connecting Hong Kong, Macau, and Zhuhai—three major cities on the Pearl River Delta in China. The HZM Bridge was designed to last for 120 years and cost ¥127 billion (US$18.8 billion) to build. The cost of constructing the Main Bridge was estimated at ¥51.1 billion (US$7.56 billion) funded by bank loans and shared among the governments of mainland China, Hong Kong and Macau. Originally set to be opened to traffic in late 2016, the structure was completed on 6 February 2018 and journalists were subsequently taken for a ride over the bridge. On 24 October 2018, the HZMB was opened to the public after its inauguration a day earlier by Chinese leader Xi Jinping. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turkey
Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with a East Thrace, small portion on the Balkans, Balkan Peninsula in Southeast Europe. It shares borders with the Black Sea to the north; Georgia (country), Georgia to the northeast; Armenia, Azerbaijan, and Iran to the east; Iraq to the southeast; Syria and the Mediterranean Sea to the south; the Aegean Sea to the west; and Greece and Bulgaria to the northwest. Cyprus is located off the south coast. Turkish people, Turks form the vast majority of the nation's population and Kurds are the largest minority. Ankara is Turkey's capital, while Istanbul is its list of largest cities and towns in Turkey, largest city and financial centre. One of the world's earliest permanently Settler, settled regions, present-day Turkey was home to important Neol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Istanbul
Istanbul ( , ; tr, İstanbul ), formerly known as Constantinople ( grc-gre, Κωνσταντινούπολις; la, Constantinopolis), is the List of largest cities and towns in Turkey, largest city in Turkey, serving as the country's economic, cultural and historic hub. The city straddles the Bosporus strait, lying in both Europe and Asia, and has a population of over 15 million residents, comprising 19% of the population of Turkey. Istanbul is the list of European cities by population within city limits, most populous European city, and the world's List of largest cities, 15th-largest city. The city was founded as Byzantium ( grc-gre, Βυζάντιον, ) in the 7th century BCE by Ancient Greece, Greek settlers from Megara. In 330 CE, the Roman emperor Constantine the Great made it his imperial capital, renaming it first as New Rome ( grc-gre, Νέα Ῥώμη, ; la, Nova Roma) and then as Constantinople () after himself. The city grew in size and influence, eventually becom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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