What Is a Check Dam?
A dam is a water-retaining structure that intercepts river channels to raise water levels or regulate flow. Reservoirs can be formed to raise water levels, regulate runoff, and concentrate heads for flood control, water supply, irrigation, hydropower generation, and improved shipping. The river regulation buildings that adjust the river regime and protect the bank beds are also called dams, such as spur dams, shun dams and submerged dams.
- [shu bà]
Dam history
- The earliest dam in the world was a 15-meter-high stone masonry dam built by the Egyptians on the Nile in 2900 BC to supply water to the capital of Ophes. The oldest dam still in use today is in Iraq, and it was built in 1300 BC. From 700 BC to 250 BC, Assyrians, Babylonians, and Persians built several dams for irrigation. During the same period, various dams were also built in Yemen, Sri Lanka, India, and China, such as China's Dujiangyan, which was built about 240 BC. The ancient Romans built a 12-meter-high building in Prospina, Spain, with concrete as the core, which can be regarded as the pioneer of modern filling dams. Another one built in the city of Konal
- dam
- In March 2016, it was confirmed by an expert field visit: the water conservancy system found outside the ancient city of Liangzhu in Hangzhou is the earliest known large-scale water conservancy project in China and the earliest dam in the world. It has been 4700 to 5100 years ago. The "Dayu Water Treatment" is still 1,000 years old. Experts suggest that the water conservancy system be included in the Liangzhu site protection scope as soon as possible, and included in the research scope of Liangzhu ancient city application value. [2] See the figure on the bottom right.
- During the 100 years before the end of World War II, experience in designing and building dams has progressed in many ways. For example, the Hoover Dam built in the United States in 1936 is a gravity arch dam designed using advanced theory. The Peckburg dam, completed in 1940, has an earthwork volume of 96 million cubic meters and was the world's largest hydraulic project at that time.
- The largest dam in the world today is the Three Gorges Dam built by China. The total length of the dam crest is 3035 meters and the dam height is 185 meters.
Dam purpose
- Power generation, stable water flow / irrigation, flood prevention, wasteland reclamation, water conversion, water landscape, etc.
Dam type
- 1. According to the structure and stress characteristics, it can be divided into:
- Gravity dam
- arch dam
- Buttress dam
- Prestressed dam
- 2. According to the drainage conditions, it can be divided into:
- Non-overflow dam
- Overflow dam
- 3 According to the dam materials, it can be divided into:
- Earth rock dam
- Masonry dam
- Concrete dam
- Rubber dam, etc.
- 4 According to whether the dam can move, it can be divided into:
- Fixed dam
- Active dam
- 5. According to the historical development process of dam engineering technology, it can be divided into:
- Ancient dam
- Modern dam
- Modern dam
- Hinged dam
Dam site
- One of the best places for building the dam is a narrow river valley; the valley side can then serve as a natural wall. The main function of the structure of the dam will be to fill the gap by the creek channel to the left of the natural reservoir line. Sites are usually places where white space becomes a minimum required storage capacity. The most economical arrangement is often a composite structure such as a masonry dam flanked by earth embankments. Flooding the current use of land should be dispensable.
- Important others engineering and engineering geological considerations when constructing a dam include:
- Permeable surrounding rocks or soil
- Earthquake Disadvantages
- Landslide and stable slope
- Peak flood process
- Reservoir siltation
- Environmental impacts on river fisheries, forests and wildlife
- Impact on human habitation
- Compensation for flooded and resettled land
- Removal of toxic materials and buildings from the proposed reservoir area
Above the dam
- Reservoir formation
- Building a dam on a river creates a reservoir upstream of the river. The water in the reservoir will spread to the surrounding area, flooding the original habitat. To date, more than 400,000 square kilometers of land have been flooded due to the construction of the dam. The newly created reservoir has a larger surface area than the original river, allowing more water to be evaporated. This could reduce the river's water depth by 2.1 meters per year. According to recent research, reservoirs have also increased greenhouse gas emissions. The original flooding of the reservoir flooded the original vegetation, causing carbon-rich plants and trees to die and decompose. Rotten tissues emit large amounts of carbon into the atmosphere. Rotten plants sink into the bottom of the oxygen-free reservoir. Due to the lack of flowing water to increase the oxygen content of the water, it eventually breaks down into methane.
- ecosystem
- Dams can also be a barrier to animal migration between upstream and downstream habitats, such as salmon in the United States and Europe. Dams prevent them from spawning upstream, threatening their reproduction and reducing the number of fish. Therefore, various measures have been taken to leave channels for fish. New dams often have artificial "fish paths" or "fish ladders". There are also places where barges are used to transport schools of fish to spawn upstream. Fish migrating downstream will also be blocked by dams, resulting in a reduction in the number of fish migrating downwards, unless they can safely swim out of the spillway. Flooding of reservoirs can also change wetlands, forests and other habitats around rivers. Ecosystems in riparian and downstream areas have also been damaged. In rivers without dams, their natural flooding supports particularly rich biological species around the river banks. The establishment of dams has reduced the occurrence of flooding and has had a negative impact on downstream flood plains that rely on seasonal flow. The relatively constant ecosystems formed by reservoirs and rivers have greatly reduced the number of wildlife species supported. The dam intercepted the sediment that nourished the downstream ecosystem. Some endemic species are unable to survive environmental changes, and new species will settle here. However, because dams change the environment in which surrounding ecosystems are accustomed, dam construction almost always reduces species diversity.
- Sediment
- "The river contains sediments of different shapes, sizes, and thicknesses. These sediments will be brought downstream by the river to form various landforms, including: deltas, alluvial fans, braided rivers, ox yoke lakes, river banks, etc. However, the construction of dams It prevents the sediment from flowing downstream, gradually eroding the original landforms downstream and increasing the sediment content in the reservoir. Although the speed of sediment deposition varies between dams and rivers, the increase in sediment content will eventually lead to Reservoir water storage has decreased. "
Below the dam
- Eroded water temperature
- Compared to the absence of a dam, the water in the reservoir is hotter in winter and cooler in summer. When the reservoir water flows into the river, the temperature of the river water changes accordingly. This will affect the flora and fauna in reservoirs and rivers, making their native environment unfamiliar. In the Towy River, significant reductions in salmon and brown trout catches have been shown to be related to lower water temperatures caused by the Llyn Brianne dam built in the 1960s. Recent changes in fish stocks in the Snake River and Klamath area have also spurred new research and conservation projects aimed at reducing stress caused by temperature changes.
Dam outside the dam
- Impact on humans
- Although dams are beneficial to humans in many ways, they can also create harmful effects that are comparable to this. A frequently hidden fact is that artificial lakes caused by dams often become breeding grounds for many diseases. For example, in tropical regions, animals carrying harmful species such as mosquitoes (carrying malaria agents) and snails (carrying schistosomiasis) can rely on the slow flow of water The advantages of the dam are multiplying. The impact of dams on the environment: Another disadvantage to humans is that if dams are built too close to their homes, relocation is imminent. The Three Gorges Dam built in China is one such example. The Three Gorges Dam has taken up a lot of land, forcing more than 1 million people to relocate. Dr. Michael Sernia of the World Bank and Dr. Thayer Scarder of the California Institute of Technology said: "Relocation related to dams has three impacts on society: economic disaster, psychological trauma and society."
- Ecological impact
- The dam inevitably changes the hydrological characteristics of the dam area and upstream and downstream, including flood pulse patterns, sediment processes, water temperature processes, etc., which will affect riverbed scour and the relationship between rivers (lakes) and lakes, and may significantly change the water that inhabits them. Vivid plant communities, this change can have fatal consequences for some aquatic animals (especially fish) that are highly dependent on river continuums or river-lake complexes. Some fish like to live in rapids (whether feeding or breeding), and the construction of dams will lead to their decline [3] .
- Dams cut off reproductive migration pathways for some fish, often with devastating consequences. For example, in the Elva River in Washington, U.S., about 400,000 salmon were spawned by the river each year, but after the dam was built, fewer than 3,000 salmon came to spawn because they lost 90% of their spawning grounds. Expensive fish passes were added later, but to no avail. In the 1970s, there were more than 10,000 Chinese sturgeon breeding populations in the Yangtze River. The Gezhouba was completed in 1981, which prevented the reproductive migration of Chinese sturgeon broodstock, which fell to about 2176 in 1983-1984 and 203 in 2005-2007. -257 tails, with only a few dozen tails remaining in 2010, and are now in a critical state [4] . According to IUCN, dams are the main cause of nearly one-fifth of global freshwater fish extinction, threats, or endangerment in the past century. Nearly three-quarters of German freshwater fish and two-fifths of American freshwater fish have been affected by it. Affect [3] .
- Impact on earth
- Dams cause climate change. This is due to the production of methane, a greenhouse gas, caused by dams. The water in the reservoir is layered and lacks oxygen at the bottom, causing anaerobic decomposition of the organism and releasing methane. Climate Change and Dams: An Analysis of the Linkages Between the UNFCCC Legal Regime and Dams. Due to climate change, the following are possible impacts:
- Dams are beautifully landscaped if properly constructed, but they can damage the environment
- Rising sea levels (possibly flooding lower altitudes)
- Climate zone moves towards poles
- Ecosystems may face new climate pressures
- Rainfall and water evaporation may change, affecting water sources
- Dams also affect the rotation of the earth. The reservoirs of all dams in the world hold more than 2.4 cubic miles of water and weigh about 10 billion tons. More water was rearranged closer to the earth's axis, thereby increasing the rotation of the earth. At present, the acceleration of the Earth's rotation is considered to have no adverse effects on the global environment and humankind, but it will continue to consider its long-term effects on global movement.
Dam dam damage
- If structures are damaged or significantly damaged, dam failures are generally catastrophic. Conventional deformation monitors seepage, from the loss and before a structural damage occurs, a larger dam is necessary to anticipate any issues and permit corrective actions to be taken. In such problematic situations, most dam consolidation mechanisms allow reservoirs to be lowered or even discharged. Another solution could be rock grouting-pressure pumping Portland cement slurry into weakly fractured rocks.
- During armed conflict, the dam will be considered as a "facility" containing dangerous forces due to the massive impact of possible damage to the civilian population and the environment. As such, it is protected by the rules of International Humanitarian Law (IHL) and will not be made an object of attack if that may lead to serious losses among the civilian population. Promoting certification, a protective sign consists of three bright orange circles placed on the same axis as defined by IHL rules.
- The main causes of dam failure include improper spillway design (South Fork Dam), geological instability caused by changes in water level during filling or poor surveys (Vajont Dam, Malpasset), insufficient maintenance, especially pipelines for export (Lawn Lake Dam, val? Di Stava Dam collapse), extreme rainfall (Shakidor Dam) and people, computer or design errors (Buffalo Creek Flood, Valley Dike Reservoir, Taum Sauk Pumped Storage Plant).
- A well-known example of deliberate dam failure (prior to the above ruling) was the RAF Dambusters attacked Germany during World War II (codenamed "operational punishment"), three German dams were selected to be destroyed in order to have access to German infrastructure And the impact of manufacturing and power capabilities Ruhr and Eder rivers. The attack became the basis for several films.
Dam famous dam
- 1. Three Gorges Dam
- On December 14, 1994, the construction of the Three Gorges Dam project, the world's largest hydropower project, officially started. It is located in Sandouping, Yichang City, Hubei Province, in the middle of the Xiling Gorge, 38 kilometers away from the downstream Gezhouba Water Control Project. The Three Gorges Dam project includes two parts: the main building project and the diversion project. The total project investment is 95.46 billion yuan (calculated at the price at the end of May 1993), of which the hub project is 50.09 billion yuan; the resettlement fee of 1.13 million resettlers is 30.07 billion yuan. , Substation engineering 15.3 billion yuan. The total construction period of the project is 17 years from 1993 to 2009, which will be carried out in three phases, and the project will be completed by 2009. The dam is a concrete gravity dam with a total length of 3,035 meters, a height of 185 meters, a normal water storage level of 175 meters, and a total storage capacity of 39.3 billion cubic meters, of which the flood prevention storage capacity is 22.15 billion cubic meters, which can withstand a once-in-a-century flood. The two power stations with 26 generators generate an average annual output of 84.9 billion kWh. The shipping capacity will be increased from the existing 10 million tons to 50 million tons, and a 10,000-ton fleet can directly reach Chongqing, while the transportation cost will also be reduced by 35%.
- After the completion of the Three Gorges Dam, a giant reservoir with a length of 600 kilometers will be formed, becoming a new rare landscape in the world. The Three Gorges Dam adopts staged water storage. After the river was closed on November 8, 1997, the water level was raised to 10-75 meters, and all landscapes of the Three Gorges were not affected. In June 2003, after the completion of the second phase of the project, the water level was raised to 135 meters. The flooded areas will be relocated, and the remaining scenic spots will be basically preserved. In 2006, the water level of the Yangtze River was raised to 156 meters, and only the gate of Quyuan Temple was flooded and will be rebuilt. After the completion of the entire Three Gorges Project in 2009, the water level will be raised to 175 meters. The stone carvings will be relocated, and the gate of Shibaozhai will be flooded by 1.5 meters. At present, plans are being made to build a dam for protection. At that time, Yuyin Mountain, where Shibaozhai is located, will become a lonely mountain surrounded by water, which is even more legendary. The majesty of other attractions remains unchanged. With the formation of man-made lakes along the river and the improvement of navigational conditions, many attractions originally scattered around the Three Gorges will be easier to reach, such as the Little Three Gorges and Shennongxi.
- 2.Itaipu Dam
- In the vast jungles of South America, there is a rolling river, the Parana River, which borders Argentina and Paraguay in southern Brazil. The Paraná River, the second largest river in South America, crosses the Vietnam-US continent and passes through Brazil, Paraguay, and Argentina into the Atlantic Ocean. Due to frequent floods, residents are forced to move out of their homes and wait for the water to return before they can return to their homes to repair their homes. The Indians called the Parana River the "Father of Water" and it carried red muddy water. At Iguazu Falls, the spectacular scene of "three thousand feet flying straight down" can be described as shaking.
- The South American countries east of the Andes are the places with the most abundant water resources on the earth. The river systems with abundant flow such as the Amazon, La Plata, and Parana nourish the rich civilization of the basin. However, it is regrettable for mankind to lean back on the tree and not enjoy the cold. The continuous flow of the Parana River does not benefit humankind, but merely harms one side, and even sighs how many visionaries. Brazil has experienced two power and energy crises since the economy took off in the 1970s. Out of profound lessons and anticipation of energy demand for future economic and social development, the Brazilian government resolutely decided to cooperate with Paraguay to build the then largest hydropower station in the world, Itaipu Dam. In 1974, Brazil and Paraguay signed the Itaipu Agreement and decided to create an Itaipu joint venture company to jointly build a dam to develop the water resources of the Parana River, which is the river between the two countries.
- 3.Almendra Dam
- Almendra Dam is located on the Tormes, a tributary of the Douro River in the province of Salamanca, Spain. The nearest city is Almendra. The concrete arch dam has a maximum dam height of 202m and a total storage capacity of 2.649 billion cubic meters. The initial installed capacity of the power station is 540,000 kW, and the expanded capacity in the later period is 270,000 kW, with an average annual power generation of 1.3 billion kW · h. The project was mainly used for power generation. Construction began in 1965 and was completed in 1970.
- The river valley is narrow at the dam site, the bedrock is granite, and there is a gneiss belt on the right bank of the auxiliary dam. The design seismic intensity is 8 degrees. The area of the control basin above the dam site is 7,100 square kilometers, with an average annual runoff of 1.609 billion cubic meters, an average annual flow of 51 cubic meters per second, an effective reservoir capacity of 2.475 billion cubic meters, an inundation area of 86.50 square kilometers, and a total length of 306 km of the bank. The design flood peak flow is 5300 cubic meters / second, the maximum storage level of the reservoir is 731.5m, the normal storage level is 730m, and the minimum operating water level is 643m.
- 4.Hoover Dam
- The Hoover Dam is located in northwestern Arizona, on Interstate 93, at the junction of Nevada and northwestern Arizona, and travels approximately 40 kilometers southeast from Las Vegas. The project is huge, and after its completion, it will play a huge role in the development of industry and agriculture. Therefore, it occupies an important position in the ranks of world water conservancy projects. The construction of the Hoover Dam cost a lot of money and mobilized a large amount of input. It was completed and delivered in 1936. It is an arched gravity artificial concrete dam. The dam is 220 meters high, 200 meters wide at the bottom, 14 meters wide at the top, and 377 meters long. Such a huge dam is rare in the world. It lies like a giant dragon lying on the ground and looks very powerful. After the dam was completed, it played a huge role in the development of industry and agriculture. Therefore, it occupies an important position in the ranks of world water conservancy projects.
- 5.Big Dixans Dam
- The world's highest concrete gravity dam. It is located on the Dixans River, a tributary of the Rhone River in Switzerland, with a controlled drainage area of 357 square kilometers and a total reservoir capacity of 400 million cubic meters. The valley at the dam site is V-shaped. The maximum dam is 285 meters high and the top of the dam is 695 meters long. The bedrock is good granite gneiss and has good impermeability, but curtain grouting is still done at a depth of 200 meters. In order to adapt to the terrain and geological conditions, the dam axis is a polyline. Because the storage capacity is large and the amount of incoming water is small, there is no other drainage structure except the dam body only has a bottom hole with a drainage volume of 10 cubic meters per second. The total installed capacity of several hydropower stations under the dam is 1.3 million kilowatts. The project started in 1953 and was completed in 1962.
- It is the tallest concrete gravity dam in the world and the highest dam in Europe. The largest dam is 285 meters high and the top is 695 meters long. The dam is located on the Dixans River, a tributary of the Rhone River in Switzerland. The dam site is V-shaped, forming a 4-km-long artificial lake-Lake Diss. During the high water season, the lake can reach a depth of 284 meters and hold 400 million cubic meters of water. The Rhone River water is channeled through pipes to three hydropower stations with a total installed capacity of 1.3 million kilowatts.
- The dam is built on the Dixans River, a tributary of the Rhone River, with a large storage capacity and a small amount of incoming water. Therefore, the dam has only a bottom hole with a discharge of 10 cubic meters per second, and there are no other drainage structures. Glacier snowmelt is the main source of water storage in the reservoir, so the water level of the reservoir changes with seasonal changes. Usually the water level reaches its highest peak at the end of September, and gradually decreases with the onset of winter, reaching the lowest point in April of the following year.
- Switzerland is not the largest country in Europe, but its air pressure is the highest in the entire European continent. This dam is used to intercept the water of the Dixans River. When the dam is full, the water depth is about 1,000 feet and the water capacity exceeds 400 million cubic meters. As for the height of the dam, it is strange that the river where the dam is located (Dixans River) is very small. In fact, the water in the dam is gathered by a tunnel system of more than 100 kilometers to collect water from the Dixans and other rivers. This water comes mainly from glaciers. The dam was filled with water in 1957, submerging the former dam that has stood here since the 19th century.
- 6.Crown Dam
- The Crohn dam is an arch dam in Iran. It was built just right on a rocky and narrow canyon. Its curves not only have aesthetic characteristics, but its arches also press the water flow below the dam. This just strengthens its foundation.
- 7.Vaiang Dam
- Vaion dam is located in the lower reaches of the Vaion River, a tributary of the Piave River in the eastern Italian Alps. The closest city is Vaion. It is about 2km from the estuary of the Vaion River that merges into the Piave River. Find treasure
- The concrete double-curved arch dam has a maximum dam height of 262m, a total reservoir capacity of 169 million cubic meters, and a hydropower station installed capacity of 0.9 million kW. Construction year 1956 ~ 1960 (5 years).
- 8.Glen Canyon Dam
- The Glen Canyon Dam is built on the Colorado River in Arizona against the backdrop of beautiful Colorado scenery. As can be seen from the surrounding environment, this place is relatively dry, and the mission of the dam is to store water for this particularly arid part of the United States. It is 216 meters high and the arched top is 470 meters long. It has been criticized for its impact on local flora and fauna, but it meets the needs of communities in three states. This dam is based on the natural conditions of the Glen Canyon in this area, and dams are erected on both sides of the canyon to intercept the Colorado River water for hydropower generation and regulation.
- Built between 1957 and 1963, it was the second tallest dam in the United States (216 meters). The dam is managed by the US military and provides free guided tours to the power station at the bottom of the dam. After the dam was completed in 1963, it began to close the gate and store water, which led to the formation of Lake Powell, named in honor of the first General Powell who drifted the river and suggested the development of water conservancy. Because of its huge volume, it has been storing water for 17 years. It was not filled until 1980, and it is now the second largest artificial lake in the United States. Glen Canyon National Recreation Area (Glen Canyon National Recreation Area) was established in 1972, this resort area is very large, across the states of Utah and Arizona, developed a lot of water sports, coupled with the scenery on both sides of the Great Lakes, is A veritable resort.
- 9.Dvorak Hydropower Station
- The bedrock of the Dvorak Dam site is hard granite gneiss. Most of the dam foundation is slightly weathered, and a small part is moderately weathered. Faults in the dam foundation have a great impact on dam construction. The right abutment fault is characterized by a large inclination angle, which is inclined to the northwest by 80 ° -90 °, and the left abutment fault has a small inclination angle, which is inclined to the south by 20 ° -50. °. The bedrock is very good. Four large shear zones or faults and three small shear zones were found during construction. The dam site is an earthquake-prone area with no active faults found nearby, and the seismic intensity is 7-8 degrees.
- The catchment area above the dam site is 6,320 square kilometers, with an average annual flow of 159.6 cubic meters / second, a measured maximum flow of 2,830 cubic meters / second, and a possible maximum peak flow of 1,1600 cubic meters / second. 1370 cubic meters / second and 2080 cubic meters / second. The maximum water storage level of the reservoir is 489.17m, the operating water level is 440.44 487.68m, the total storage capacity is 4.28 billion cubic meters, the effective storage capacity is 2.497 billion cubic meters, and the reservoir area is 69.2 square kilometers.
- 10 Inguri dam
- The Inguri Dam is located in the Zhival Gorge of the river in the Republic of Georgia, near the Turkish border. The dam is a double-curved arch dam with a maximum dam height of 271.5m. It is currently the highest arch dam in the world. Underground hydropower station, with 5 units installed, with a single unit capacity of 260,000 kW, and another 4 power stations on the tailwater canal, with an installed capacity of 340,000 kW and a total installed capacity of 1.64 million kW. The project started construction in 1965, the first unit generated electricity in 1978, and the project was completed in 1982. The total storage capacity of the reservoir is 1.11 billion cubic meters, and the effective storage capacity is 676 million cubic meters. The project has comprehensive benefits such as power generation and flood prevention.
- The dam area has a subtropical climate, with an average annual temperature of 14 ° C, a monthly average temperature of less than -5 ° C in winter, and a monthly average temperature of 23 ° C in summer. The annual frost-free period is as long as 287 days, the winter snow layer is 24cm thick, and the annual precipitation is 2100mm.
- The bottom of the river valley in the dam site area is 50-70m wide, the left bank slope is 35 °, and the right bank is 45 °. It belongs to a high earthquake area, the seismic intensity is 8 degrees, and the seismic load of the structure is designed according to 9 degrees. The dam foundation consists of limestone, dolomite, and Palem dolomite (lower Cretaceous). The rock layer is a monoclinic structure, inclined downstream, with an inclination of 50 ° -60 °, and the upper part of the river bed is slightly anticline-curved. The bedrock is hard, the instantaneous compressive strength is about 80-90MPa, cracks are developed, the deformation modulus of the rock in the unloading zone does not exceed 4000-8000MPa or lower, and the deformation modulus of the rock in the natural complete zone is below 13000MPa. According to the structural characteristics, physical and mechanical characteristics of the rock and the degree of fissure development, the bedrock is divided into 6 layers with a layer thickness of 40-150m.
- The main faults at the dam site are: marginal faults of the Jurassic and Cretaceous rock contact zone at 1-1.5km upstream of the dam; the Yingguli anticline fault located 1.5km upstream of the dam, with a vertical fault distance of 1000m; tectonic faults With a break distance of 100 120m, there is no modern deformation activity. There are about 20 cracks that belong to mild structural damage, and the opening is larger than 10cm and smaller cracks. The riverbed gravel alluvial layer at the dam site is 38m thick. The karst phenomenon occurs only locally in the basement of the left bank of the high plateau, and there are pore-like karsts, and fissures and bedding are carbonate filtration.
- The area of the control basin at the dam site is 4060 square kilometers, with an average annual flow of 155 cubic meters per second and a maximum measured flow of 950 cubic meters per second. In the millennium, the flood flow was 2120 cubic meters / second.
- 11. Nagarjuna sagar dam
- Nagar Juna Sagar Dam Nagar Juna Sagar Dam is still the largest dam in Asia and is also the oldest. It was built in 1956 and it took a long time to come into use. Since modern construction equipment was not available in the early days of Indian democracy, the dam could only be constructed of stone instead of concrete. The project took a long time to complete until 1969, and the top gate was installed three years later, and the dam was put into use. Seventy thousand people participated in the project, and about 200 people died in the accident.
- 12. Sayan-shushensk hydropower station
- The largest hydropower station in the Soviet Union. Built on the Yenisei River in Siberia. Large units with a single unit capacity of 640,000 kilowatts are used, with a total installed capacity of 6.4 million kilowatts and an annual power generation of 23.5 billion kilowatts.
- The Sayan --- Shushensk Hydropower Station started construction in September 1968 and was completed in 1987, after 20 years. During the period, temporary water inlets and temporary turbine runners were used to generate electricity in advance at a low water head of 60 meters (equivalent to 32% of the designed water head of 194 meters) and achieved good economic benefits. It is an important experience in the construction of Soviet hydropower stations .
- The average annual temperature in the upper reaches of the Yenisei River is 1.5 ° C, and the lowest temperature is -42 ° C. The construction conditions in the dam area are poor in winter. The average annual runoff of the river at the dam site of the power station is 46.7 billion cubic meters, with an average flow of 1480 cubic meters per second. The total storage capacity of the reservoir is 31.3 billion cubic meters. The water depth of the reservoir is 40 meters, and the corresponding effective storage capacity is 15.3 billion cubic meters. The dam is 242 meters high, the tallest gravity arch dam in the world to date. The top of the dam is 1083 meters long and the dam foundation is 100 meters wide. The water front is vertical, the plane is curved, and the radius is 600 meters. There are 11 overflow holes with a designed water discharge of 13,600 cubic meters per second. The power plant building is also arc-shaped downstream of the dam, with a total length of 288 meters including the installation room.
- The power station uses a mixed flow turbine with a diameter of 6.77 meters and a rated speed of 142.8 rpm. The design head is 194 meters, the flow capacity is 358 cubic meters per second, and the rated output is 650,000 kilowatts. At a maximum head of 212 meters, the output can reach 735,000 kilowatts. The runner weighs 156 tons and is transported by water as a whole. The rated output of the generator is 715,000 kVA, and the maximum output is 736,000 kVA. The rotor adopts forced air cooling, and the stator adopts water internal cooling.
- The transformer uses expansion unit junctions, and every two generators are connected to a set of single-phase step-up transformers with a capacity of 1.6 million kVA. Each single-phase transformer is 533,000 kVA. The power produced by the power station is boosted to 500 kV by a transformer and connected to Siberian United Power via an ultra-high voltage transmission line