"ha" column or row of the kana syllabary
Introduction to DamsMomosuke Fukuzawa
Reading: Momosuke Fukuzawa (福ざわ桃スケ), a businessman active from the late Meiji period to the early Showa period (1926-1989). He was mainly active in the Japanese electric power industry and was nicknamed the "King of Electric Power in Japan. Momosuke Fukuzawa, formerly known as Momosuke Iwasaki, was born in Arako Village, Yokomi-gun, Musashi Province...
"ha" column or row of the kana syllabaryflash board
Read : flashboard Flashboard is a device used to collect driftwood, trash, and other floating debris in a reservoir and ...
Introduction to Damsweir (usu. for irrigation)
Headworks are a series of structures such as water intakes and weirs that are used to intake agricultural water from rivers and streams. A headworks is a structure with a high leve...
Introduction to Damshyetograph
The hyetograph is a graph showing the amount of rainfall over time. The horizontal axis shows time, and the vertical axis shows rainfall on the vertical axis. This allows us to see the time...
Introduction to Damshydrograph
A hydrograph is a graph showing changes in the amount of water flowing into a dam or river and the water level over time. The graph shows time on the horizontal axis and flow rate and water level on the vertical axis. Creating this graph is...
Introduction to Damsstonemason
Reading: HARI-ISHIKOU AKA: - Tension masonry is one of the construction methods mainly used for rockfill dams and other slopes, in which larger stones (500-1000 mm in diameter) are laid down and then further smaller stones are filled in between them. It is very fine with no unevenness...
Introduction to Damsunequal arch dam
The arch dam is an arch-type concrete dam with a thickened concrete section on both banks of the embankment. When an arch dam is built in a wide V-shaped valley, the load on both banks of the arch can be too much, so this type of unequal...
Introduction to Damssub-dam
A sub-dam is a weir generally installed downstream of a dam to prevent scouring by buffering water falling from the flood discharge. It is a type of damming. In most cases, the height of the embankment does not exceed 15 m. However, if the original dam is large, a secondary dam...
Introduction to Damscombined dam
Composite dam → Combined dam
Introduction to Damsfillet
A fillet is a reinforcing thickening section placed at the bottom of the upstream side of a dam embankment. They are installed when the strength of the concrete dam cannot be maintained or to ensure stability against overturning. They are installed in a triangular shape so that the upstream slope is slower.
Introduction to DamsSurface water intake system
A surface intake facility is a 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. In addition, dams for power generation are sometimes installed to prevent turbid water. In some dams, aging surface intake facilities are replaced with selective intake facilities to improve reliability, operability, and maintenance management.
Introduction to Damsemergency flood discharge
An emergency flood discharge is a gate that prevents overflow of a dam during a flood. It is used in the event of a flood that is too large to be discharged by the normal flood discharge. In most cases, the emergency flood discharge is located near the top of the embankment.
Introduction to Damsnon-flood season
The non-flood season refers mainly to the winter months, when precipitation is low. This means that the water level of the dam lake is higher. The period varies from dam to dam and is set in detail. ⇔Flood season
Introduction to Damsbuttress dam
Buttress dams, also known as "support-wall dams," are dams that use concrete walls for support. There are only six such dams in Japan, and the Mitaki Dam (Tottori Prefecture), completed in 1937, was the last buttress dam in Japan. Because cement was an expensive material before World War II, buttress dams, which require less cement than gravity-type concrete dams, attracted attention and were constructed. However, as cement became less expensive, it was difficult to find engineers to work on the formwork, maintenance was not easy and costly, and there were durability problems.
