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Aquatic Organism Passage
A culvert is a structure that channels water past an obstacle or to a subterranean waterway. Typically embedded so as to be surrounded by soil, a culvert may be made from a pipe, reinforced concrete or other material. In the United Kingdom, the word can also be used for a longer artificially buried watercourse. Culverts are commonly used both as cross-drains to relieve drainage of ditches at the roadside, and to pass water under a road at natural drainage and stream crossings. When they are found beneath roads, they are frequently empty. A culvert may also be a bridge-like structure designed to allow vehicle or pedestrian traffic to cross over the waterway while allowing adequate passage for the water. Dry culverts are used to channel a fire hose beneath a noise barrier for the ease of firefighting along a highway without the need or danger of placing hydrants along the roadway itself. Culverts come in many sizes and shapes including round, elliptical, flat-bottomed, open-b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cast In Place Concrete
Cast-in-place concrete or Cast-in-situ concrete is a technology of construction of buildings where walls and slabs of the buildings are cast at the site in formwork. This differs from precast concrete technology where slabs are cast elsewhere and then brought to the construction site and assembled. It uses concrete slabs for walls instead of bricks or wooden panels, and formwork is used for both walls and roof. Advantages of this technology are strength of the building, insulation, and versatility for different types of buildings. A disadvantage is the high amount of labor required to install and remove formwork. See also * Precast concrete * Formwork Formwork is Molding (process), molds into which concrete or similar materials are either precast concrete, precast or cast-in-place concrete, cast-in-place. In the context of concrete construction, the falsework supports the shuttering mold ... References Building engineering {{civil-engineering-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grout
Grout is a dense substance that flows like a liquid yet hardens upon application, often used to fill gaps or to function as reinforcement in existing structures. Grout is generally a mixture of water, cement, and sand, and is frequently employed in efforts such as pressure grouting, embedding rebar in masonry walls, connecting sections of precast concrete, filling voids, and sealing joints such as those between tiles. Common uses for grout in the household include filling in tiles of shower floors and kitchen tiles. It is often color tinted when it has to be kept visible and sometimes includes fine gravel when being used to fill large spaces (such as the cores of concrete blocks). Unlike other structural pastes such as plaster or joint compound, correctly mixed and applied grout forms a water-resistant seal. Although both grout and its close relative, mortar, are applied as a thick suspension and harden over time, grout is distinguished by its low viscosity and lack of lime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Environmental Protection Agency
The Environmental Protection Agency (EPA) is an independent agency of the United States government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it began operation on December 2, 1970, after Nixon signed an executive order. The order establishing the EPA was ratified by committee hearings in the House and Senate. The agency is led by its administrator, who is appointed by the president and approved by the Senate. The current administrator is Lee Zeldin. The EPA is not a Cabinet department, but the administrator is normally given cabinet rank. The EPA has its headquarters in Washington, D.C. There are regional offices for each of the agency's ten regions, as well as 27 laboratories around the country. The agency conducts environmental assessment, research, and education. It has the responsibility of maintaining and enforcing national standards under a variety of environmental laws, in consultat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bureau Of Land Management
The Bureau of Land Management (BLM) is an agency within the United States Department of the Interior responsible for administering federal lands, U.S. federal lands. Headquartered in Washington, D.C., the BLM oversees more than of land, or one-eighth of the United States's total landmass. The Bureau was created by United States Congress, Congress during the presidency of Harry S. Truman in 1946 by combining two existing agencies: the United States General Land Office and the United States Grazing Service, Grazing Service. The agency manages the federal government's nearly of subsurface Mineral rights, mineral estate located beneath federal, state and private lands severed from their surface rights by the Homestead Act of 1862. Most BLM public lands are located in these 12 Western United States, western states: Alaska, Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington (state), Washington and Wyoming. The mission of the BLM is "to susta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Federal Highway Administration
The Federal Highway Administration (FHWA) is a division of the United States Department of Transportation that specializes in highway transportation. The agency's major activities are grouped into two programs, the Federal-aid Highway Program and the Federal Lands Highway Program. Its role had previously been performed by the Office of Road Inquiry, Office of Public Roads and the Bureau of Public Roads. History Background With the coming of the bicycle in the 1890s, interest grew regarding the improvement of streets and roads in America. The traditional method of putting the burden on maintaining roads on local landowners was increasingly inadequate. In 1893, the federal Office of Road Inquiry (ORI) was founded; in 1905, it was renamed the Office of Public Roads (OPR) and made a division of the United States Department of Agriculture. Demands grew for local and state government to take charge. With the coming of the automobile, urgent efforts were made to upgrade and moderniz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion
Erosion is the action of surface processes (such as Surface runoff, water flow or wind) that removes soil, Rock (geology), rock, or dissolved material from one location on the Earth's crust#Crust, Earth's crust and then sediment transport, transports it to another location where it is deposit (geology), deposited. Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as ''physical'' or ''mechanical'' erosion; this contrasts with ''chemical'' erosion, where soil or rock material is removed from an area by Solvation, dissolution. Eroded sediment or solutes may be transported just a few millimetres, or for thousands of kilometres. Agents of erosion include rainfall; bedrock wear in rivers; coastal erosion by the sea and Wind wave, waves; glacier, glacial Plucking (glaciation), plucking, Abrasion (geology), abrasion, and scour; areal flooding; Aeolian processes, wind abrasion; groundwater processes; and Mass wastin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrodynamic Scour
lang=en, upright=1.3, Mechanism of formation, alt=sketch Hydrodynamic scour is the removal of sediment such as silt, sand and gravel from around the base of obstructions to the flow in the sea, rivers and canals. Scour, caused by fast flowing water, can carve out scour holes, compromising the integrity of a structure. It is an interaction between the hydrodynamics and the geotechnical properties of the substrate. It is a notable cause of bridge failure and a problem with most marine structures supported by the seabed in areas of significant tidal and ocean current. It can also affect biological ecosystems and heritage assets. Mechanism Any obstruction within flowing water will produce changes in velocity within the water column. The flow changes that occur in the vicinity of the substrate may cause differential movement in the bed materials near the obstruction. The magnitude of these changes varies with stream velocity, feature shape and substrate character. Generally the str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stream Bed
A streambed or stream bed is the bottom of a stream or river and is confined within a Stream channel, channel or the Bank (geography), banks of the waterway. Usually, the bed does not contain terrestrial (land) vegetation and instead supports different types of aquatic vegetation (aquatic plant), depending on the type of streambed material and water velocity. Streambeds are what would be left once a stream is no longer in existence. The beds are usually well preserved even if they get buried because the banks and canyons made by the stream are typically hard, although soft sand and debris often fill the bed. Dry, buried streambeds can actually be underground water pockets. During times of rain, sandy streambeds can soak up and retain water, even during dry seasons, keeping the water table close enough to the surface to be obtainable by local people. The nature of any streambed is always a function of the flow dynamics and the local geologic materials. The climate of an area wil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stream Banks
In geography, a bank is the land alongside a body of water. Different structures are referred to as ''banks'' in different fields of geography. In limnology (the study of inland waters), a stream bank or river bank is the terrain alongside the bed of a river, creek, or stream. The bank consists of the sides of the channel, between which the flow is confined. Stream banks are of particular interest in fluvial geography, which studies the processes associated with rivers and streams and the deposits and landforms created by them. Bankfull discharge is a discharge great enough to fill the channel and overtop the banks. The descriptive terms ''left bank'' and ''right bank'' refer to the perspective of an observer looking downstream; a well-known example of this being the southern left bank and the northern right bank of the river Seine defining parts of Paris. The shoreline of ponds, swamps, estuaries, reservoirs, or lakes are also of interest in limnology and are somet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kanał Nowa Ulga, Wał Miedzeszyński, Warszawa 004
''Kanał'' (, ''Sewer'') is a 1957 Polish film directed by Andrzej Wajda. It was the first film made about the 1944 Warsaw Uprising, telling the story of a company of Home Army resistance fighters escaping the Nazi onslaught through the city's sewers. The film is adapted from the story “They Loved Life” by Jerzy Stefan Stawinski. ''Kanał'' is the second film of Wajda's War Trilogy, preceded by '' A Generation'' and followed by '' Ashes and Diamonds''. The film was the winner of the Special Jury Award at the 1957 Cannes Film Festival. Plot It is 25 September 1944, during the last days of the Warsaw Uprising. Lieutenant Zadra leads a unit of 43 soldiers and civilians to a new position amidst the ruins of the now isolated southern Mokotów district of Warsaw. The composer Michał manages to telephone his wife and child in another part of the city that is being overrun by the Germans. After a few words, she tells him that the Germans are clearing the building and that they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composite Material
A composite or composite material (also composition material) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a material with properties unlike the individual elements. Within the finished structure, the individual elements remain separate and distinct, distinguishing composites from mixtures and solid solutions. Composite materials with more than one distinct layer are called ''composite laminates''. Typical engineered composite materials are made up of a binding agent forming the ''matrix'' and a Filler (materials), filler material (particulates or fibres) giving ''substance'', e.g.: * Concrete, reinforced concrete and masonry with cement, lime or Mortar (masonry), mortar (which is itself a composite material) as a binder * Composite wood such as glulam and plywood with wood glue as a binder * Reinforced plastics, such as fiberglass and fibre-rein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
