The worlds largest green energy base is coming: quite two Three Gorges

 The worlds largest green energy base is coming: quite two Three Gorges

Super technology 1: Low-temperature cement concrete for decades of research and development, the use of the dam

The dam of Wudongde Hydropower Station is a Concrete Double-Curvature Arch Dam with 718 meters above sea level at the bottom and 988 meters above sea level at the top of the dam. The maximum dam is 270 meters high. However, the thickness of the dam bottom is only 51 meters. Such a proportion makes the Wudongde Hydropower Station the thinnest 300-meter arch dam in the world at present. The slender body must bear the impoundment of tens of millions of super-large hydropower stations, which undoubtedly puts forward unprecedented high requirements for the quality of concrete placement.

arch dam

Wudongde Hydropower Station is located in the dry and hot valley of Jinsha River, where the sunshine is intense and the temperature of the dam construction platform reaches over 40 degrees at the hottest time. The low-temperature cement concrete used in the whole dam of Wudongde Hydropower Station is a pioneer in the history of dam construction in the world.

Low-temperature cement concrete

At the construction site, CCTV financial and economic half an hour reporter saw that the concrete display temperature is 7.1 degrees, while the atmospheric temperature is 29 degrees.

Concrete temperature

Dam Casting Warehouse

According to the construction requirements, the pouring temperature of the dam concrete can not exceed 18 degrees. In order to ensure the construction requirements under high temperature, a sprayer is set up to reduce the environmental temperature of the warehouse. Even if the outdoor temperature is thirty or forty degrees, the temperature in the warehouse can still be controlled at 20-30 degrees.

Spray machine

In order to fully perceive the temperature of all parts of the dam, the concrete temperature of Wudongde dam can be real-time perceived by embedding thermometers and cooling pipes in the concrete. Through the intelligent water supply system, the water flow can be automatically adjusted to realize the intellectualization of concrete cooling process.

Embedded thermometer

Super Technology 3: More than 10,000 grouting holes to prevent seepage of dam foundation hills

The deepest grouting and drainage corridor of the Wudongde Dam crosses the bottom of the dam and extends to the hills on both sides. In order to prevent the upstream water from seeping into the downstream, some curtain holes were drilled on the ground. The maximum depth of the curtain holes is 110 meters.

Drainage corridor

It is reported that the total construction volume of the main curtain is 500,000 meters, and there are about 10,000 grouting holes. The whole curtain is connected like a big curtain, which keeps the upstream water firmly in front of the dam.

curtain grouting

Super Technology IV: Dedication of Spider Man in Active Web of Slope Protection Artifact

The lower reaches of Jinsha River in Wudongde Hydropower Station belong to deep canyon. Long-term rainwater scouring and sun exposure, mountain and slope at any time there is a risk of rolling stones collapse, it can be said that even a very small stone grain can break down the steel plate.

In order to eliminate the hidden dangers, in the early stage of construction, the construction party first used Spider Man to peel off the surface gravel and floating soil on the natural slope on both sides of the bank, and then fixed the mountain body with more than 50,000 shallow anchors and more than 4,000 deep anchors. These anchor cables penetrate several tens of meters deep into the mountain body, tightly fixing the rock and the mountain body.

Bolt and cable

After that, one million square meters, equivalent to 200 football fields, will be laid to cover the entire slope. In the excavated slope area, shotcrete should be grouted to fix the whole rock mass, and passive protective nets should be set at different heights.

Active protective net

Since the introduction of these protective nets, many major dangers have been successfully eliminated. In addition, monitoring sensors are buried in the mountain, geological hazard monitoring system is established, and linked with hydrometeorological center. Once the slope has slight displacement deformation, the system can make early warning in time.

Super Technology 5: The height of the main powerhouse of underground power station ranks first in the world!

The distance between the hills on both sides of the dam top of Wudongde Hydropower Station is only over 300 meters. Because of the narrow space, in addition to the 270-meter-high dam building, more building structures are hidden in the mountains and underground. As the main power generating equipment of hydropower station, the main powerhouse of hydro-turbine unit is located in the mountains on both sides of the dam.

The excavation length of the main powerhouse of Udongde underground power station is 333 meters, with a span of 32.5 meters and a height of 89.8 meters, which is equivalent to a high building of nearly 30 stories. This height breaks the world record of the excavation height of the main powerhouse of the underground power station.

Main Workshop of Udongde Underground Power Station

The Wudongde Hydropower Station is scheduled to release and store water in July 2020 and put into operation in December 2021. As a green energy source, after the completion of the Udongde Power Station, about 12.2 million tons of standard coal can be saved annually, and 30.5 million tons of carbon dioxide and 104,000 tons of sulfur dioxide can be reduced.

In the future, four cascade power stations on the Jinsha River, namely, Wudongde, Baihetan, Xiluodu and Xiangjiaba, will have a installed capacity of 46.46 million kilowatts, which is equivalent to two Three Gorges Project. With an annual output of about 190 billion kilowatt-hours, they will become the worlds largest landmark green energy engineering base in the 21st century.

Source: CCTV News Client Responsible Editor: Qiao Junyi_NBJ11279