Introduction to Dams

dam terminology

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CFRDCFRDThe term "Concrete Face Rockfill Dam" is an abbreviation of "Concrete Face Rockfill Dam", which translates directly to "Concrete Intercepting Rockfill Dam(?)". Concrete Face Rockfill Dam. The upstream face of a rockfill dam is covered with concrete to prevent water from seeping into the embankment.
DWLDWL→Design flood level
light-water reactorlight-water reactor→Minimum water level
NWLNWL→ Always full water level
RCDRCDThis is an application of RCC (Roller Compacted Concrete), a construction method originally used for airport runway pavement in the United States and road pavement in Japan, to dams. Abbreviation of "Roller Compacted Dam-concrete method.
SWLSWL→ Surcharge water level

"a" column or row of the kana syllabary

earth damahsudamu (tile matching the base of a kong) (mahjong)Also known as an "earth-fill dam. This is a dam made by layering earth as the material. Because it is relatively easy to construct, it is not suited for large-scale dams, but rather for small-scale dams such as reservoirs.
arch damjeer atAlso known as an "arched concrete dam" or "arched dam. The shape of the dam allows the water pressure of the dam lake received by the embankment to be dispersed to the bedrock on either side of the embankment, thus making the embankment itself thinner and reducing construction costs. However, this type of dam is only suitable for construction on bedrock that can support a considerable amount of water pressure.
right bank (shore), ,left bank (of a river)Ugan, Saigan.Looking in the downstream direction, the right side is the "right bank" and the left side is the "left bank.
orifice gateOrihui StreetA discharge gate installed at a depth of less than 25 m below the permanently full water level regulates the water level of the dam lake and the amount of water flowing downstream.

classification for Japanese verb with the dictionary form ending in "ku

river lawundersea navigation systemAccording to Article 1 of the River Law, its purpose is "to provide for the protection of the rivers andfloodThe purpose of the river basin is to contribute to the preservation and development of the national land and thereby maintain public safety and promote public welfare through comprehensive management of the river basin so that disasters caused by storm surges and other disasters are prevented, the river is used appropriately, the normal function of running water is maintained, and the river environment is improved and preserved. The article also states that dams are to be managed in accordance with Article 44-51. The description of dams is found in Articles 44-51, which states, "A dam (a dam installed with a license under Article 26, Paragraph 1, for storing or taking water from a river, the height of which is 15 m or more from the foundation to the top of the embankment; the same shall apply hereinafter) is a structure that is designed and constructed for the purpose of retaining or taking water from a river. The same shall apply hereinafter). In the event that the condition of a river changes due to the installation of said dam and the function of said river at the time of flooding is reduced, the person who installs such dam (which means a dam with a height of 15 m or more from the foundation ground to the top of the embankment) as specified by a Cabinet Order shall install facilities necessary to maintain said function or take alternative measures in accordance with the instructions of the river administrator. The following is a summary of the provisions of the Act.
Temporary drainage tunnelpseudo-DISMISSION SUMMARYWhen a dam is constructed, a tunnel is dug from upstream to downstream of the dam site to dam up the river, thus diverting the overflowing upstream water downstream.
corridor connecting an annex to a pond-side building (in traditional palatial-style architecture)inspectorA passageway used to check for damage inside the dam embankment. Normally, it is off-limits to all but authorized personnel. However, if the dam is designated as a "dam open to the community," it may be used as a tour course.
Foundation Groundbulletin board systemIndicates the ground that is used to support the weight of the dam. Depending on the dam, the foundation ground may be quite deep. Incidentally, the embankment height, which indicates the height of the dam, is the height measured from the foundation to the top of the embankment.
base high-flow-ratebasic multiple-loadingThis is the condition of the river before the dam was constructed, and refers to the river flow at the time of a flood that is expected to occur once every 100 years (1/100 chance flow rate). Takamizu" is used to avoid mistakenly reading the word "kozui" as "high water.
reverse osmosis pondinversion of the word order in a sentenceThey exist in large hydroelectric power plants where the flow increases during the day and decreases at night. A dam also built downstream of a power plant to store water is called a "reverse control reservoir," and a certain amount of water is released to regulate the downstream flow.
catwalkKyatookeA narrow passageway installed downstream of the embankment wall, especially in concrete dams, for work during the construction phase of the dam and for inspection after completion.
crest gateheaven given to me by GodIt is mainly used for emergency flood discharge and is installed at the crest of the dam.
Planned composting capacityplanning capacityCapacity of sediment assumed to flow into the dam lake over a 100-year period.
Planned high water flow rateplanned multiple-loadingIn contrast to the "basic high water flow rate," this indicates the river flow rate when flooding is regulated by a dam after the dam is constructed. As with the "basic high water flow rate," this reading is also called "takamizu" to avoid mistakenly reading "takamizu" as "kozui" (meaning "high water" in Japanese).
cable crane"Beaubourg-en" (trademarked development name of mifepristone)A crane used in dam construction to transport materials. It carries the material from the aggregate plant to the dam embankment, so cables are usually stretched across the dam.
momentum reducerprimary schoolThe water flowing out of the flood discharge is so vigorous that it could scour the water fall area, which is prevented.
rough-coated rockgap (in a mountain ridge)A mountain from which materials needed to build a dam are extracted.
floodfloodA flood occurs when the flow from upstream to the dam lake is higher than usual, even if the dam is not overflowing.
flood seasontaro stemsThis refers to periods of high precipitation, such as the rainy season and typhoon season (mainly from June to October). Therefore, the water level of the dam lake is lower just before the flood season.
Flood stage limit water levelarea constrained waterA water level established at a dam for the purpose of flood control, which prevents flooding by lowering the water level below the full water level at all times.
Flood control capacityhigh capacity (e.g. nuclear reactor)The flood control capacity is the surcharge water level minus the flood stage limit water level. Flood control is carried out within this capacity.
Flood dischargefloodwall gateA gate facility used to channel water from a dam lake downstream. The "gate" is a facility that allows water to flow downstream from a dam.ordinary flood dischargeand "emergency flood dischargeThere are two types of "A" and "B".
flood capacityhigh capacityCapacity from the permanent full water level or flood stage limit to the surcharge level.
aggregateaggregateIt is a raw material for concrete.
conduitpatiently (endure)→ Water discharge pipe

"sa" column or row of the kana syllabary

surcharge water leveltea water purification systemSurcharge means "overload" or "overload" and refers to the level at which water can be stored in a dam lake to its limit during a flood.
minimum water levelthe most appropriateIt refers to the water level at the top of the sediment, assuming that the sediment capacity of the dam is horizontal.
experimental floodultrathinnessThis is a test to check for any problems with the dam after it is completed. The water is stored up to the surcharge level and then reduced to the minimum level.
dead-water capacitywater consumptionThe volume between the top of the sediment capacity and the lowest water level.
gravity arch damgravitational atomosphereThis dam has the advantages of both gravity and arch concrete dams.
gravity-fed concrete damgravitational root-crystal programThe dam is made of concrete and can support water pressure by the weight of the embankment itself.
normal level of water supplyholding one's head highThe highest water level that can be stored in a dam lake for water utilization purposes.
ordinary flood discharge(one's) traveling companionsA gate that regulates the flow of water downstream from a dam lake.
water rightswater rightsRights to use water from rivers and other sources. As for dams, they are divided into agricultural water, water for water supply, industrial water, etc.
design flood leveldesign layoutThe water level of the dam lake at the time of the dam's maximum flood, which is expected to occur about once every 200 years at a given time.
selective water withdrawalselective waterTo take water from the dam lake, which varies in temperature and turbidity depending on its depth, for different purposes.
Total storage capacitytotal allowable useIt is the sum of sediment capacity, dead water capacity, water diversion capacity, and flood control capacity.

classification for Japanese verb with the dictionary form ending in "tsu

sediment level(proper) format (e.g. of an essay)The height of the top surface when the planned composting capacity is leveled and composted.
Composting capacitytolerance level→ Planned sediment capacity
damdeceiveIf Article 44 of the River Law is to be used as the definition of a dam, it is defined as "a dam installed to store or withdraw running water from a river, the height of which is 15 m or more from the foundation ground to the top of the embankment.
dam-sitedebtor from a defeated countryDam Location.
dam axisdumminessA line based on the upstream face of the dam top.
Dam top elevationleaving a market indicating a change in an item's priceHeight from sea level to top edge?
multipurpose dammulti-purpose programA single dam serves multiple purposes, including flood control, power generation, industry, and irrigation.
Reservoir areafreshwater areaArea of dammed lake at full water level at all times.
Hollow gravity damhollow-resistance operationA gravity concrete dam with a hollowed-out embankment.
Bank heightresistanceDam Height. The height from the foundation ground to the top of the dam.
Dam volumemooringsVolume of the dam embankment. The sum of the materials that make up the dam.
Bank lengthlow toneLength of dam embankment.
telemeterstereotyped epithettelemeter] A device that decodes, indicates, or records measured quantities sent as electrical signals from a distant place (from Shinjirin Sanseido). Telemeters at dams mainly transmit measurement data from rain gauges and water level gauges to the management office.
Top (Crest)PegasusThe upper part of the dam embankment.
conduit(professional) group active at the same timeIt is a channel that runs from the overflow area downstream of the dam to the dam dam attenuator, and is used to ensure the proper flow of water from the flood discharge.

"ha" column or row of the kana syllabary

buttress damROTSAlso known as a "support wall dam," it is a dam with a concrete wall support system. There are only six such dams in Japan, and Mitaki Dam is the last buttress dam in Japan.
non-flood seasondried giant elephant ear stem from Higo province (eaten or used as a sex aid)It mainly indicates the winter months and refers to a period of low precipitation. Therefore, the water level of the dam lake is higher.
emergency flood dischargeadjudicated judgment by a court of competent jurisdiction (judgement)A gate that prevents a dam from overflowing during a flood.
Surface water intake systemSurface Mount DeviceA facility that withdraws water from the surface where the water temperature is warmer than the lower levels. It has the advantage of not affecting crops and organisms.
filletI'm going to ...A reinforcing thickening section installed upstream of the dam embankment. It is installed when the strength of the concrete dam cannot be maintained.
Combined Dam (combine dam)compound damu (a compound damu being a compound damu of a compound verb)A dam with both a concrete dam and a fill dam. The banks of the river where the dam is to be installed have different geological conditions, and usually a concrete dam is installed on the bank with firm ground, while a fill dam is installed on the bank with loose ground.
sub-damduplicateGenerally, a weir is installed on the downstream side of a dam to buffer water falling from the flood discharge.
unequal arch damUntouchable AhtuadamuArch-type concrete dam: A dam with thickened concrete sections on both banks of the embankment. It is used for dams that add too much load to both banks.
drainpipedrainpipeA pipe installed for flood control and downstream discharge.

"ya" column or row of the kana syllabary

Effective water storage capacityeffective doseThe total storage capacity of a dam lake minus the sediment capacity and dead water volume.

"ra" column or row of the kana syllabary

radial gatepornographic artFan-shaped gate. It is opened and closed around the fan.
irrigation and drainage systemRRSA facility used to release water from a dam. It is mainly used when the downstream flow is low, or when the water level is lowered from the normal full level to the flood stage limit.
usable capacitywater-based feeCapacity from the minimum water storage level to the full water level at all times.
lip wrapriotousThey are installed on the outside of the embankment of a fill dam to protect the embankment from erosion by water.
Roller gatetranslucent light-emitting diodeRollers are attached to the plate of the gate for opening and closing. Even if high water pressure is applied to the gate, it can be opened and closed easily.
rockfill damRokufirdamA dam made of rock, sand, or soil. It is suitable for dams with soft bedrock on both sides of the dam. Therefore, they are not suitable for large dams.
This article was written by.
Shin Jinma

Dam enthusiast who loves Momosuke Fukuzawa / Dampedia and Dam News administrator / Certified Dammeister (01-018) by the Japan Dam Foundation / Started selling discharge caution goods.

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