On December 30, 1970, the first large-scale hydropower station on the Yangtze River, the Gezhouba Water Conservancy Project, started construction. The China Energy Construction Gezhouba Group emerged as the times require, and the world continues to grow in strides from the Yangtze River.

Today, let us follow together. Comrade Zhang Yaohua's story has witnessed the magnificent development history of China's hydropower. Since the founding of the People’s Republic of China, China has built more than 20 large-scale hydropower stations with a capacity of over one million kilowatts, and hundreds of medium-sized hydropower stations have become veritable "World Dam Museum". If the unit is the heart of the hydropower station, then the dam is the skeleton of the hydropower station and the key to the success of the entire hydropower station. With the completion of Gezhouba, the first dam of the Yangtze River in Wanli, and the "Five Golden Flowers" (Shuikou, Yantan, Wuqiangxi, Geheyan and Manwan), in the 1990s, the Three Gorges of the Yangtze River, Xiangjiaba and Wudong Giant projects such as Germany have started one after another, representing the highest level of dam construction in my country, and setting up monuments. On September 18, 1997, I came to the Three Gorges as the chief engineer of the Mechanical and Electrical Department of the Three Gorges Command. In participating in the construction of the second phase of the Three Gorges Dam, how to perform fast, high-quality and high-strength construction was a severe test for me. .

At that time, the expert group of the State Council put forward very high requirements for the quality of the project. The standards for the implementation of the Three Gorges Project were not the standards issued by the ministry, but the "Three Processes Project Quality Standards" which were more detailed and more demanding than the standards issued by the ministry. During the construction, we refined every process and every technical plan, and created a world record of 2.6 million cubic meters of concrete pouring without cracks through refined management. Xu Chunyun, the director of the Three Gorges Project at the time, screened the dam's crack-prone construction sites. After the screening was completed, he said, "I really didn't find a crack, it's amazing!" During the construction of the Three Gorges Project, I was most impressed by the third phase. Construction of RCC cofferdam. On December 16, 2002, the roar of heavy trucks and bulldozers resounded across the Xia River, and the RCC cofferdam opened the curtain of high-intensity construction. This cofferdam is a key control project connecting the second and third phases of the project. The top elevation of the cofferdam is 140 meters, the maximum bottom width is 107 meters, and the maximum weir height is 121 meters. The total amount of concrete pouring is 1,106,600 cubic meters. The first weir".

According to the overall construction schedule of the Three Gorges Project, the construction of the RCC cofferdam started the foundation pit cleaning on January 20, 2003, and the top of the weir must be poured on June 10. There is only one dry period during the construction period, and the water will be blocked when completed. Its tight construction period, high construction intensity, and high quality requirements can be called "the best in the world". More than 1.1 million cubic meters of concrete will be poured in a dry period. How to dry it? At the beginning of the planning, everyone felt the pressure on the face: there was no experience to follow, the industry was also skeptical, and "110" became a lingering number for all cadres and employees. For rapid construction, the headquarters and the project department undertaking this task held multi-level meetings and discussions, made a fuss on design and plan innovation, and proposed the concept of simplifying concrete partitioning and dividing joints, reducing layering, and adopting prefabricated gallery The rapid construction plan of roads and prefabricated formwork explored a set of continuous and efficient construction modes for multi-disciplinary and multi-work cross mechanized operations. From the opening of the first warehouse of RCC on December 26, 2002 to the pouring to the top of the weir on April 16, 2003, it took only 110 days, creating a monthly concrete of 476,000 cubic meters, a maximum monthly rise of 27.9 meters, and the largest daily The pouring intensity of 21,000 cubic meters, the maximum continuous pouring height of 57.2 meters and many other world records have laid a solid foundation for the Three Gorges Project on June 15, 2003, when the reservoir was impounded to a water level of 135 meters, and the first batch of units to generate electricity in October. The smooth pouring of the RCC cofferdam marks a historic breakthrough in the quality and speed of the RCC construction of large-scale water conservancy projects in my country.

After the Three Gorges Project, Xiangjiaba was another milestone in the construction of the dam we undertook. On January 15, 2007, the Spring Festival was only four days away. I came to Xiangjiaba to participate in the construction of the first phase of the project. What impressed me the most was the treatment of bad geological bodies in the deep foundation pit. The success or failure of the treatment of bad geological bodies and the pouring of the dam foundation is the key to whether the Xiangjiaba Hydropower Station can be closed in the second phase on time. Gezhouba people worked together and innovated boldly in the construction of Xiangjiaba, and succeeded in overcoming a series of construction problems including the installation and operation of the largest-scale caisson group of hydropower in China, known as the “first span in Asia”, and the installation and operation of three translational cable cranes. , The first-stage earth-rock cofferdam was demolished from underwater to land-based demolition, and the conventional concrete pouring of the top arch of the diversion bottom hole was changed to the non-demolition steel top arch pouring, so that the second-stage closure was realized as scheduled. At the celebration of the closure of Longkou, Peng Gang, director of the Owner’s Construction Department, excitedly said to Yang Jixue, then chairman of Gezhouba Group: “If you choose Gezhouba, you will choose success.”

In July 2008, the company once again won the bid for the main construction tasks of Xiangjiaba Hydropower Station Youfei and the spillway section. During the excavation of the foundation pit, because the foundation surface encountered a wide range of unfavorable geological bodies, the foundation surface elevation was lowered, and the amount of excavation and pouring work increased. The dam pouring time lags behind the total project schedule by six months. How to do? The owner proposed to find Gezhouba. In the in-depth exchanges and discussions, we put forward the bold idea and suggestion of "changing the dam section from normal concrete to roller compacted concrete with an elevation of 240 meters below the alveolar slot and an elevation below 265 meters". After many times of design and expert demonstrations, the scheme was approved. The construction bureau quickly mobilized various resources and organized it carefully, creating a new high of 22,000 cubic meters per day, breaking the world record of 21,000 cubic meters per day of roller compacted concrete created by the construction of the Three Gorges Project. In the two key tower belt cranes and feeding line equipment that determine the vertical transportation and distribution of concrete, we boldly innovated and increased the pouring height of the tower belt crane by 36 meters. With the joint efforts of all employees of the Construction Bureau, the Xiangjiaba Hydropower Station dam was poured to the top on schedule on April 12, 2013, and the water level was raised in advance. A 20.27-meter-long normal concrete core sample was taken out of the poured dam, setting the world record for the longest concrete core sample of hydraulic structures at that time. The heat went to the cold, and it was hard for eight years. In 2015, the Xiangjiaba project entered the final stage, and the construction of the Wudongde Hydropower Station, which the company participated in, is in full swing. On November 10, 2015, with a transfer order, I went upstream and went to the Wudongde site as the chief engineer of the construction bureau.

In 2017, the Wudongde construction site was in a construction situation of multi-specialties and multiple types of work. The work was complicated and many problems needed to be solved urgently. The first concrete warehouse of the dam was poured on March 16, 2017, which was also independently constructed by the Gezhouba people. The world's thinnest 300-meter super high arch dam. How to build a "seamless dam" has always been the pursuit of Gezhouba people and the dream of generations of hydropower people. The occurrence of cracks is a systemic problem and a worldwide problem in hydropower projects.

Aiming at the characteristics of Wudongde Hydropower Station in the dry and hot valley and the large temperature difference between day and night, we organized technical personnel to find out the crux of cracks such as cantilever height control, long interval control, water insulation control and dam height difference control. The control point is determined, how to achieve it? There is another problem. If traditional construction methods are still used, there will definitely be problems, and innovation is the only option. Innovation is easy to talk about, but difficult to realize. The application of low-heat cement in the whole dam section, intelligent grouting, intelligent vibrating, intelligent temperature control, automatic climbing formwork, and the application of a batch of "three new" technologies such as the whole dam without cover weight consolidation grouting. In 2018, Udonde achieved the "Double Hundred" goal. Only the participants can experience the hardship.

On July 29, 2020, General Secretary Xi Jinping gave an important instruction to the Wudongde Hydropower Station project: adhere to the new development concept, bravely climb the new peak of science and technology, and strive to build quality projects to better benefit the people. We responded with actions: The Wudongde Dam, the left bank underground powerhouse, and the spillway tunnel, which were separately contracted by Gezhouba, successfully passed the three-stage impoundment acceptance and the flood test of the Yangtze River this year. The dam's various operating indicators all meet the design And better than the design requirements.Editor/Xing Wentao