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Winter Road
A winter road is a seasonal road only usable during the winter, i.e. it has to be re-built every year. This road typically runs over land and over frozen lakes, rivers, swamps, and sea ice.Proskin et al, 2011. Guidelines for the Construction and Operation of Winter Roads, Transportation Association of Canada.- IHSA, 2014. Best practices for building and working safely on ice covers in Ontario, Mississauga, Ontario, 43 p.- NorthWest Territories Transportation, 2015. Guidelines for safe ice construction, Yellowknife, NWT, Canada, 44 p.Spencer, P.A., Strandberg, A.G. and Maddock, W.A., 2008. Ice and toundra road design for module transport, Proceedings of the 8th International Conference on Ships and Marine Structures in Cold Regions (ICETECH), Banff. Segments of a winter road that cross an expanse of floating ice are also referred to as an ice road or an ice bridge. The foundations underlying over-land segments is most often native soil or muskeg frozen to a given depth, and local ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tibbitt To Contwoyto Winter Road
Tibbitt to Contwoyto Winter Road is an annual ice road first built in 1982 to service mines and exploration activities in the Northwest Territories and Nunavut in Northern Canada. Between long, the road is said to be the world's longest heavy haul ice road and operates for eight to ten weeks starting in the last week of January. Most of the road (85%–87%) is built over frozen lakes, , with the remaining built on over 64 land portages between lakes. Construction and operation The winter road is constructed by Nuna Logistics and RTL-Robinson every January and takes about six weeks to complete. The first vehicle along each season is a Swedish-made Hägglund army-type reconnaissance vehicle designed to float if it falls through the ice; it tows an ice-thickness-detecting sonar. This is followed by road building equipment including "specialized low ground pressure equipment". The road, built extra wide to avoid blockages during blizzards and to allow opposing trucks to pass, is k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roads In Canada By Type
A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation. There are many types of roads, including parkways, avenues, controlled-access highways (freeways, motorways, and expressways), tollways, interstates, highways, thoroughfares, 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 other than rails or air strips open to public traffic, primarily for the use of road motor vehicles running on their own wheels", w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snow Road
A snow road is a type of winter road, which is a road that is used or trafficable only in the winter.Adam 1978Abele 1990Proskin et al. 2011 Snow roads make up some or all of the on-land segments of a winter road. The snow is either compacted in place or, when there is not enough of it, is hauled from elsewhere, then compacted. The snow may be processed, for instance, by agitation to reduce the size of the particles before compaction.Lang et al 1997 Additional snow is also used to help protect the vegetation and as a means of improving trafficability. This snow, sometimes referred to as 'snow pavement', can be compacted to various level, depending on requirements and available equipment – a higher compaction will accommodate heavier vehicles and higher tire pressures.Russell-Head et al 1984 To increase the road's load capacity and its resistance to wear, water can be added onto the snow surface, resulting in a denser pavement and the formation of an ice cap. Ultimately, with a su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climate Change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global average temperature is more rapid than previous changes, and is primarily caused by humans burning fossil fuels. Fossil fuel use, deforestation, and some agricultural and industrial practices increase greenhouse gases, notably carbon dioxide and methane. Greenhouse gases absorb some of the heat that the Earth radiates after it warms from sunlight. Larger amounts of these gases trap more heat in Earth's lower atmosphere, causing global warming. Due to climate change, deserts are expanding, while heat waves and wildfires are becoming more common. Increased warming in the Arctic has contributed to melting permafrost, glacial retreat and sea ice loss. Higher temperatures are also causing m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aviation
Aviation includes the activities surrounding mechanical flight and the aircraft industry. ''Aircraft'' includes fixed-wing and rotary-wing types, morphable wings, wing-less lifting bodies, as well as lighter-than-air craft such as hot air balloons and airships. Aviation began in the 18th century with the development of the hot air balloon, an apparatus capable of atmospheric displacement through buoyancy. Some of the most significant advancements in aviation technology came with the controlled gliding flying of Otto Lilienthal in 1896; then a large step in significance came with the construction of the first powered airplane by the Wright brothers in the early 1900s. Since that time, aviation has been technologically revolutionized by the introduction of the jet which permitted a major form of transport throughout the world. Etymology The word ''aviation'' was coined by the French writer and former naval officer Gabriel La Landelle in 1863. He derived the term from the v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airport
An airport is an aerodrome with extended facilities, mostly for commercial air transport. Airports usually consists of a landing area, which comprises an aerially accessible open space including at least one operationally active surface such as a runway for a plane to take off and to land or a helipad, and often includes adjacent utility buildings such as control towers, hangars and terminals, to maintain and monitor aircraft. Larger airports may have airport aprons, taxiway bridges, air traffic control centres, passenger facilities such as restaurants and lounges, and emergency services. In some countries, the US in particular, airports also typically have one or more fixed-base operators, serving general aviation. Operating airports is extremely complicated, with a complex system of aircraft support services, passenger services, and aircraft control services contained within the operation. Thus airports can be major employers, as well as important hubs for tourism ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portage
Portage or portaging (Canada: ; ) is the practice of carrying water craft or cargo over land, either around an obstacle in a river, or between two bodies of water. A path where items are regularly carried between bodies of water is also called a ''portage.'' The term comes from French, where means "to carry," as in "portable". In Canada, the term "carrying-place" was sometimes used. Early French explorers in New France and French Louisiana encountered many rapids and cascades. The Native Americans carried their canoes over land to avoid river obstacles. Over time, important portages were sometimes provided with canals with locks, and even portage railways. Primitive portaging generally involves carrying the vessel and its contents across the portage in multiple trips. Small canoes can be portaged by carrying them inverted over one's shoulders and the center strut may be designed in the style of a yoke to facilitate this. Historically, voyageurs often employed tump lines on t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bending
In applied mechanics, bending (also known as flexure) characterizes the behavior of a slender structural element subjected to an external load applied perpendicularly to a longitudinal axis of the element. The structural element is assumed to be such that at least one of its dimensions is a small fraction, typically 1/10 or less, of the other two.Boresi, A. P. and Schmidt, R. J. and Sidebottom, O. M., 1993, Advanced mechanics of materials, John Wiley and Sons, New York. When the length is considerably longer than the width and the thickness, the element is called a beam. For example, a closet rod sagging under the weight of clothes on clothes hangers is an example of a beam experiencing bending. On the other hand, a shell is a structure of any geometric form where the length and the width are of the same order of magnitude but the thickness of the structure (known as the 'wall') is considerably smaller. A large diameter, but thin-walled, short tube supported at its ends and loa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
