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Earthen Dam
An embankment dam is a large artificial dam. It is typically created by the placement and compaction of a complex semi-plastic mound of various compositions of soil or rock. It has a semi-pervious waterproof natural covering for its surface and a dense, impervious core. This makes the dam impervious to surface or seepage erosion. Such a dam is composed of fragmented independent material particles. The friction and interaction of particles binds the particles together into a stable mass rather than by the use of a cementing substance. Types Embankment dams come in two types: the earth-filled dam (also called an earthen dam or terrain dam) made of compacted earth, and the rock-filled dam. A cross-section of an embankment dam shows a shape like a bank, or hill. Most have a central section or core composed of an impermeable material to stop water from seeping through the dam. The core can be of clay, concrete, or asphalt concrete. This type of dam is a good choice for sites wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tarbela
Tarbela ( pnb, ) or Torbela ( ps, توربېلا) is one of the 44 union councils, administrative subdivision, of Haripur District in the Khyber Pakhtunkhwa province of Pakistan. The name comes from the words ''tor'' (Pashto for "black") and ''bela'' (Punjabi/Hindko for "forest"). Khalabat township is divided into four sectors: Sectors 1 and 2 are called Tarbela union; sectors 3 and 4 are called Khalabat union council. Nearby Tarbela Dam got its name from this Tarbela. Festival On 1st Baisakh (April 11), the Hindu residents in the vicinity and of the Hazara plain bathe in the Indus river The Indus ( ) is a transboundary river of Asia and a trans-Himalayan river of South and Central Asia. The river rises in mountain springs northeast of Mount Kailash in Western Tibet, flows northwest through the disputed region of Kashmir, .... The assembly is religious and lasts two days. References Union councils of Haripur District {{Haripur-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Riprap
Riprap (in North American English), also known as rip rap, rip-rap, shot rock, rock armour (in British English) or rubble, is human-placed rock or other material used to protect shoreline structures against scour and water, wave, or ice erosion. Ripraps are used to armor shorelines, streambeds, bridge abutments, foundational infrastructure supports and other shoreline structures against erosion. Common rock types used include granite and modular concrete blocks. Rubble from building and paving demolition is sometimes used, as well as specifically designed structures called tetrapods. Riprap is also used underwater to cap immersed tubes sunken on the seabed to be joined into an undersea tunnel. Environmental effects Sediment effects Ripraps cause morphological changes in the riverbeds they surround. One such change is the reduction of sediment settlement in the river channel, which can lead to scouring of the river bed as well as coarser sediment particles. This can be combat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teton Dam
The Teton Dam was an earthen dam in the western United States, on the Teton River in eastern Idaho. It was built by the U.S. Bureau of Reclamation, one of eight federal agencies authorized to construct dams.Perrow, Charles. ''Normal Accidents''. New York: Basic Books, 1984. , pp.233–238 Located between Fremont and Madison counties, it suffered a catastrophic failure on June 5, 1976, as it was filling for the first time. The collapse of Teton Dam resulted in eleven deaths, and killed 16,000 livestock. The dam cost about $100 million to build and the federal government paid over $300 million in claims related to its failure. Total damage estimates have ranged up to $2 billion, and the dam was not rebuilt. History and geology Interest in building a dam in the eastern Snake River Plain had arisen for many years to control spring runoff and provide a more constant water supply in the summer. The area had suffered a severe drought in 1961, followed by severe flooding in 1962. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phreatic Line
The top flow line of a saturated soil mass below which seepage takes place, is called the Phreatic line. Hydrostatic pressure acts below the phreatic line whereas atmospheric pressure exists above the phreatic line. This line separates a saturated soil mass from an unsaturated soil mass. It is not an equipotential line, but a flow line. For an earthen dam, the phreatic line approximately assumes the shape of a parabola. See also * Phreatic ''Phreatic'' is a term used in hydrology to refer to aquifers, in speleology to refer to cave passages, and in volcanology to refer to a type of volcanic eruption. Hydrology The term phreatic (the word originates from the Greek , meaning "well" ... * Embankment dam References Hydrology Dams {{Dam-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Largest Dams In The World
The following table lists the largest man-made dams by volume of fill/structure. By general definition, a dam is a barrier that impounds water or underground streams, hence tailings dams are relegated to a separate list. Data on volume of structure is not as easily available or reliable as data on dam height and reservoir volume. Type: TE - Earth; ER - Rock-fill; PG - Concrete gravity; CFRD - Concrete face rock fill. List of largest tailings dams Type: TE - Earth; ER - Rock-fill; PG - Concrete gravity; CFRD - Concrete face rock fill. See also * List of reservoirs by volume * List of tallest dams * List of conventional hydroelectric power stations * List of largest hydroelectric power stations * List of megaprojects#Dam and hydroelectric projects References {{Structural extremes * Dams Dams Dams A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravity Dam
A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by using only the weight of the material and its resistance against the foundation to oppose the horizontal pressure of water pushing against it. Gravity dams are designed so that each section of the dam is stable and independent of any other dam section. Characteristics Gravity dams generally require stiff rock foundations of high bearing strength (slightly weathered to fresh), although in rare cases, they have been built on soil foundations. The bearing strength of the foundation limits the allowable position of the resultant force, influencing the overall stability. Also, the stiff nature of the gravity dam structure is unforgiving to differential foundation settlement, which can induce cracking of the dam structure. Gravity dams provide some advantages over embankment dams, the main advantage being that they can tolerate minor over-topping flows without damage, as the concre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth Structure
An earth structure is a building or other structure made largely from soil. Since soil is a widely available material, it has been used in construction since prehistoric times. It may be combined with other materials, compressed and/or baked to add strength. Soil is still an economical material for many applications, and may have low environmental impact both during and after construction. Earth structure materials may be as simple as mud, or mud mixed with straw to make cob. Sturdy dwellings may be also built from sod or turf. Soil may be stabilized by the addition of lime or cement, and may be compacted into rammed earth. Construction is faster with pre-formed adobe or mudbricks, compressed earth blocks, earthbags or fired clay bricks. Types of earth structure include earth shelters, where a dwelling is wholly or partly embedded in the ground or encased in soil. Native American earth lodges are examples. Wattle and daub houses use a "wattle" of poles interwoven with sti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stepped Spillway
A stepped spillway is a spillway with steps on the spillway chute to assist in the dissipation of the kinetic energy of the descending water. This eliminates or reduces the need for an additional energy dissipator, such as a body of water, at the end of the spillway downstream. Historical developments Stepped spillways, consisting of weirs and channels, have been used for over 3,500 years since the first structures were built in Greece and Crete. During Antiquity, the stepped chute design was used for dam spillways, storm waterways, and in the town water supply channels. Most of these early structures were built around the Mediterranean Sea, and the expertise on stepped spillway design was spread successively by the Romans, Muslims and Spaniards. Although the early stepped spillways were built in cut-stone masonry, unlined rock and timber, a wider range of construction materials was introduced during the mid-19th century, including the first concrete stepped spillway of the Gold ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weir
A weir or low head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the river level. Weirs are also used to control the flow of water for outlets of lakes, ponds, and reservoirs. There are many weir designs, but commonly water flows freely over the top of the weir crest before cascading down to a lower level. Etymology There is no single definition as to what constitutes a weir and one English dictionary simply defines a weir as a small dam, likely originating from Middle English ''were'', Old English ''wer'', derivative of root of ''werian,'' meaning "to defend, dam". Function Commonly, weirs are used to prevent flooding, measure water discharge, and help render rivers more navigable by boat. In some locations, the terms dam and weir are synonymous, but normally there is a clear distinction made between the structures. Usually, a dam is designed specifically to impound water behind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gabion
A gabion (from Italian ''gabbione'' meaning "big cage"; from Italian ''gabbia'' and Latin ''cavea'' meaning "cage") is a cage, cylinder or box filled with rocks, concrete, or sometimes sand and soil for use in civil engineering, road building, military applications and landscaping. For erosion control, caged riprap is used. For dams or in foundation construction, cylindrical metal structures are used. In a military context, earth- or sand-filled gabions are used to protect sappers, infantry, and artillerymen from enemy fire. Leonardo da Vinci designed a type of gabion called a ''Corbeille Leonard'' ("Leonard basket") for the foundations of the San Marco Castle in Milan. Civil engineering The most common civil engineering use of gabions was refined and patented by Gaetano Maccaferri in the late 19th century in Sacerno, Emilia Romagna and used to stabilize shorelines, stream banks or slopes against erosion. Other uses include retaining walls, noise barriers, temporary flood w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retaining Wall
Retaining walls are relatively rigid walls used for supporting soil laterally so that it can be retained at different levels on the two sides. Retaining walls are structures designed to restrain soil to a slope that it would not naturally keep to (typically a steep, near-vertical or vertical slope). They are used to bound soils between two different elevations often in areas of terrain possessing undesirable slopes or in areas where the landscape needs to be shaped severely and engineered for more specific purposes like hillside farming or roadway overpasses. A retaining wall that retains soil on the backside and water on the frontside is called a seawall or a bulkhead. Definition A wall for holding in place a mass of earth or the like, as at the edge of a terrace or excavation. A retaining wall is a structure designed and constructed to resist the lateral pressure of soil, when there is a desired change in ground elevation that exceeds the angle of repose of the soil. A basement ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
