On May 31, a new member was added to the global dam “family”. The dam of the Baihetan Hydropower Station, the largest hydropower project under construction in the world, was poured to the top. All technical indicators of the dam met the high-quality design requirements. , Marking my country’s 300-meter-level super-high arch dam construction technology has achieved the world’s lead.

The Baihetan Dam was poured to the top, announcing that the construction of the dam was successfully completed as scheduled

Baihetan Hydropower Station is currently the world's largest hydropower project under construction. It is the second cascade of the four hydroelectric cascades in the lower reaches of the Jinsha River-Wudongde, Baihetan, Xiluodu, and Xiangjiaba. The dam site is located at the junction of Ningnan County, Sichuan Province and Qiaojia County, Yunnan Province.

Baihetan Hydropower Station is another iconic project after the Three Gorges Project. It is another "national card" of China Hydropower leading the world. It is the super project that was put into operation in the first year of my country's "14th Five-Year Plan". The backbone power supply to the east is also an important part of the flood control system in the Yangtze River Basin. It has an epoch-making milestone in the history of hydropower construction.

The total installed capacity of Baihetan Hydropower Station is 16 million kilowatts, ranking second in the world; the single unit capacity is 1 million kilowatts, ranking first in the world, and its comprehensive engineering technical indicators are among the best in the world. According to the plan, the first batch of units of Baihetan Hydropower Station will be put into production before July 2021.

The dam of Baihetan Hydropower Station is a 300-meter-level super-high concrete double-curvature arch dam. The maximum dam height is 289 meters and the crest arc is 709 meters. The dam body is arranged with 6 bottom diversion holes, 7 deep flood discharge holes and 6 flood discharges. The surface hole has a complicated structure. As the world's largest giant hydropower station under construction and the most comprehensive technical difficulty, the Baihetan Hydropower Station dam construction process has created a number of world records: 300-meter high arch dam seismic parameters, the world's first; the first full dam using low-heat cement concrete; The dam withstands total water thrust of 16.5 million tons, the second in the world; the arch dam is 289 meters high, the third in the world.

According to reports, the Baihetan Hydropower Station dam is divided into 31 dam sections. The total concrete pouring of the main body of the dam is 8.03 million cubic meters, and the "volume" exceeds 3 Pyramids of Khufu. The Baihetan Dam is equipped with 7 translational cable cranes, which are the world's largest cable crane group. Each cable crane has a rated lifting weight of 30 tons, and a 9 cubic meter crane is used for vertical transportation of concrete.

The total construction period of Baihetan Hydropower Station is 144 months. During the excavation of the dam abutment, the 700-meter-high steep slope was "carved", creating a world record of a maximum of 30 meters in a single month and 300 meters in a year. The main body of the dam started concrete pouring on April 12, 2017. It has lasted 1,510 days and nights. A total of 2,253 warehouses and nearly 8 million cubic meters of concrete have been poured on the dam body.

During the more than 4 years since the dam was poured, all parties involved in the construction have been fighting day and night.

The overall balance of the dam has continued to rise in a balanced manner. The pouring volume has exceeded 2 million cubic meters for three consecutive years, setting a world record for similar projects such as annual pouring of 2.7 million cubic meters, monthly pouring of 273,000 cubic meters, and 100-day deep hole.

Baihetan Hydropower Station has overcome the world-class problem of columnar jointed basalt as a super high arch dam foundation. For the first time, the whole dam uses low-heat cement, innovatively implemented the first-stage direct burying of 100-meter gate grooves, carried out intelligent construction, and mastered a 300-meter super high arch dam The core technology of temperature control has opened a new era of world hydropower engineering, promoted technological progress in the industry, and led the innovative development of world hydropower.

The total installed capacity of Baihetan Hydropower Station is 16 million kilowatts, ranking second in the world after the Three Gorges Project. The single machine capacity is 1 million kilowatts, ranking first in the world. It is expected that all 16 generating units will be put into operation in July 2022. At that time, one day's power generation can meet the daily life of 500,000 people for a year.

The underground caverns of Baihetan Hydropower Station are the largest in the world. The total length of underground caverns is 217 kilometers, which is equivalent to 1.7 times the distance between Beijing and Tianjin.

The underground caverns of Baihetan Hydropower Station are the largest in the world. The total length of underground caverns is 217 kilometers, which is equivalent to 1.7 times the distance between Beijing and Tianjin.

The maximum discharge capacity reaches 42,348 cubic meters per second, and the entire West Lake can be filled in 6 minutes. The discharge power of the hub is the third in the world.

The reservoir capacity of Baihetan Hydropower Station is 20.627 billion cubic meters, which is equivalent to the total volume of Dongting Lake.

New type of special cement prevents temperature cracks in the dam

The construction process of Baihetan Hydropower Station involves many industrial fields such as hydropower design, major equipment manufacturing, construction management, etc., highlighting the advantages of my country's complete industrial chain in the construction of major national heavy equipment and super projects. The temperature control and crack prevention of mass concrete has always been a difficult problem in the engineering field. In order to ensure that the dam does not have temperature cracks from the source, the Baihetan dam uses a new type of special cement independently developed by my country-low-heat Portland cement concrete for the first time.

Baihetan Hydropower Station has designed and installed 16 hydro-generator units with a single unit capacity of 1 million kilowatts. It is the world's largest hydroelectric unit with a unit capacity of one million kilowatts. It is also a fully localized million kilowatt unit independently designed and manufactured by China.

It is reported that the innovation of millions of units mainly consists of two parts. One is that the generator has been increased from the original 800,000 kilowatts to 1 million kilowatts. The second innovation is the use of long and short blade runners in the water turbine, so that the entire water turbine can realize the transformation from water energy to 1 million kilowatts. The conversion of mechanical energy also realizes high-efficiency and stable operation with wide load.

As the world’s first batch of million-kilowatt hydropower units, it not only achieved a huge leap in single-unit capacity, but the technical support behind it has led to a comprehensive improvement in the technical level of my country’s entire hydropower equipment manufacturing industry. China’s hydropower has moved from being a “follow runner”. "leader".

Keywords: engineering construction, new energy

From the middle reaches of the Yangtze River to the lower reaches of the Jinsha River, the Three Gorges Group has basically built the world’s largest clean energy corridor. Help "carbon peak" and "carbon neutral" play the role of the main force of the national team.Editor/Baohongying