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Pretoria Bridge
The Pretoria Bridge is a table bridge in Ottawa, Ontario, Canada. It crosses the Rideau Canal linking the Glebe and Centretown to Old Ottawa East. The bridge was built in 1915, replacing an earlier wooden swing bridge on Argyle Street just to the north. It is a table bridge, meaning that the central portion of the bridge can be elevated to allow boats to pass underneath. Although built by the Strauss Bascule Bridge Company, the moveable span is not a bascule type but a table-type. In the late 1970s it was discovered that road salt had seriously damaged the bridge. Proposals were advanced to build a larger and higher bridge, but these were opposed by those who saw the bridge as a heritage structure. Eventually it was decided to rebuild the bridge almost exactly as it had been before. The bridge shares its name with nearby Pretoria Avenue. Pretoria Avenue, formerly Jane Street, was renamed in 1902 to commemorate the British victory in the Second Boer War and those Canadians that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Road Salt
Road salt (also known as de-icing salt, rock salt, or snow salt) is a salt used mainly as an anti-slip agent in winter road conditions, but also to prevent dust and snow build-up on roads. Various kinds of salts are used as road salt, but calcium chloride and sodium chloride (rock salt) are among the most common. The more expensive magnesium chloride is generally considered safer, but is not as widely used because of its cost and effect on structural integrity. When used in its solid form, road salt is often pre-wet to accelerate the ice-melting process. Spreading Road salt and brine are generally spread using a winter service vehicle called a salt spreader. Salt spreaders are typically added to trucks, loaders, or in the case of brine, tankers. The salt is stored in the large hopper on the rear of the vehicle, with a wire mesh over the top to prevent foreign objects from entering the spreading mechanism and hence becoming jammed. The salt is generally spread across the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Road Bridges In Ontario
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 stabilized base oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bridges In Ottawa
A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or railway) without blocking the path underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually something that is otherwise difficult or impossible to cross. There are many different designs of bridges, each serving a particular purpose and applicable to different situations. Designs of bridges vary depending on factors such as the function of the bridge, the nature of the terrain where the bridge is constructed and anchored, the material used to make it, and the funds available to build it. The earliest bridges were likely made with fallen trees and stepping stones. The Neolithic people built boardwalk bridges across marshland. The Arkadiko Bridge, dating from the 13th century BC, in the Peloponnese is one of the oldest arch bridges in existence and use. Etymology The ''Oxford English Dictionary'' traces the origin of the word ''bridg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nelson Mandela
Nelson Rolihlahla Mandela ( , ; born Rolihlahla Mandela; 18 July 1918 – 5 December 2013) was a South African Internal resistance to apartheid, anti-apartheid activist and politician who served as the first president of South Africa from 1994 to 1999. He was the country's first black head of state and the first elected in a Universal suffrage, fully representative democratic election. Presidency of Nelson Mandela, His government focused on dismantling the legacy of apartheid by fostering racial Conflict resolution, reconciliation. Ideologically an African nationalist and African socialism, socialist, he served as the president of the African National Congress (ANC) party from 1991 to 1997. A Xhosa people, Xhosa, Mandela was born into the Thembu people, Thembu royal family in Mvezo, South Africa. He studied law at the University of Fort Hare and the University of Witwatersrand before working as a lawyer in Johannesburg. There he became involved in anti-colonial and Afr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apartheid
Apartheid ( , especially South African English: , ; , ) was a system of institutionalised racial segregation that existed in South Africa and South West Africa (now Namibia) from 1948 to the early 1990s. It was characterised by an authoritarian political culture based on ''baasskap'' ( 'boss-ship' or 'boss-hood'), which ensured that South Africa was dominated politically, socially, and economically by the nation's minority White South Africans, white population. Under this minoritarianism, minoritarian system, white citizens held the highest status, followed by Indian South Africans, Indians, Coloureds and Ethnic groups in South Africa#Black South Africans, black Africans, in that order. The economic legacy and social effects of apartheid continue to the present day, particularly Inequality in post-apartheid South Africa, inequality. Broadly speaking, apartheid was delineated into ''petty apartheid'', which entailed the segregation of public facilities and social ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pretoria
Pretoria ( ; ) is the Capital of South Africa, administrative capital of South Africa, serving as the seat of the Executive (government), executive branch of government, and as the host to all foreign embassies to the country. Pretoria straddles the Apies River and extends eastward into the foothills of the Magaliesberg mountains. It has a reputation as an academic city and centre of research, being home to the Tshwane University of Technology (TUT), the University of Pretoria (UP), the University of South Africa (UNISA), the Council for Scientific and Industrial Research (CSIR), and the Human Sciences Research Council. It also hosts the National Research Foundation (South Africa), National Research Foundation and the South African Bureau of Standards. Pretoria was one of the host cities of the 2010 FIFA World Cup. Pretoria is the central part of the City of Tshwane Metropolitan Municipality which was formed by the amalgamation of several former local authorities, including B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Second Boer War
The Second Boer War (, , 11 October 189931 May 1902), also known as the Boer War, Transvaal War, Anglo–Boer War, or South African War, was a conflict fought between the British Empire and the two Boer republics (the South African Republic and Orange Free State) over Britain's influence in Southern Africa. The Witwatersrand Gold Rush caused a large influx of "Uitlander, foreigners" (''Uitlanders'') to the South African Republic (SAR), mostly British from the Cape Colony. As they, for fear of a hostile takeover of the SAR, were permitted to vote only after 14 years of residence, they protested to the British authorities in the Cape. Negotiations failed at the botched Bloemfontein Conference in June 1899. The conflict broke out in October after the British government decided to send 10,000 troops to South Africa. With a delay, this provoked a Boer and British ultimatum, and subsequent Boer Irregular military, irregulars and militia attacks on British colonial settlements in Natal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pretoria Bridge, Ottawa, 1920
Pretoria ( ; ) is the administrative capital of South Africa, serving as the seat of the executive branch of government, and as the host to all foreign embassies to the country. Pretoria straddles the Apies River and extends eastward into the foothills of the Magaliesberg mountains. It has a reputation as an academic city and centre of research, being home to the Tshwane University of Technology (TUT), the University of Pretoria (UP), the University of South Africa (UNISA), the Council for Scientific and Industrial Research (CSIR), and the Human Sciences Research Council. It also hosts the National Research Foundation and the South African Bureau of Standards. Pretoria was one of the host cities of the 2010 FIFA World Cup. Pretoria is the central part of the City of Tshwane Metropolitan Municipality which was formed by the amalgamation of several former local authorities, including Bronkhorstspruit, Centurion, Cullinan, Hammanskraal and Soshanguve. Some have proposed changi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Table Bridge
A table bridge is a moveable bridge in which the deck moves vertically. Two or four hydraulic pillars under the bridge, one or two at each end, raise the bridge deck to allow boat traffic to pass beneath it. In contrast to a lift bridge, where the deck is pulled upwards along towers, the deck of a table bridge is pushed upwards by otherwise hidden pillars. The name originates from the fact that when open it resembles a table. The total space required by a table bridge is hardly larger than the bridge deck, which is not the case with a retractable bridge. Unlike a lift bridge this type has only slight visual impact upon its surroundings when closed for use by road traffic. This is very well demonstrated by the '' Pont levant Notre Dame'' at Tournai in Belgium. Examples of table bridges Several rivers and waterways are home to multiple examples of table bridges. These include but are not limited to: :* Erie Canal in New York between Lockport and the Genesee River is home to one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bascule Bridge
A bascule bridge (also referred to as a drawbridge or a lifting bridge) is a moveable bridge with a counterweight that continuously balances a span, or leaf, throughout its upward swing to provide clearance for boat traffic. It may be single- or double-leafed. The name comes from the French term for balance scale, which employs the same principle. Bascule bridges are the most common type of movable span because they open quickly and require relatively little energy to operate, while providing the possibility for unlimited vertical clearance for marine traffic. History Bascule bridges have been in use since ancient times, but until the adoption of steam power in the 1850s, very long, heavy spans could not be moved quickly enough for practical application. Types There are three types of bascule bridge and the counterweights to the span may be located above or below the bridge deck. The fixed-trunnion (sometimes a "Chicago" bascule) rotates around a large axle that raises ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
