Research On The Construction Techniques Of The Water Intake Structure Of Large-scale Nuclear Power And Thermal Power Plants

The large-scale nuclear power or thermal power plants are always located in the river bank or coastal area, where the geological condition is often not ideal. The water intake structures of the large-scale nuclear power or thermal power plants are all large-scale hydraulic structures such as super large and deep circulation pump house caisson,large diameter water pipes and water intakes, where there is a big construction difficulty and risk. Therefore, research on the key techniques of construction of such water intake structures located in the river bank or coastal area has important significance.Based on many typical projects, this thesis investigates the key techniques of construction of water intake structures of the large-scale nuclear power or thermal power plants for the first time, using many research methods such as scheme comparison, theoretical analysis, and numerical simulation and engineering test. The main research harvests are as follows:1. This thesis investigates the key techniques and applications in engineering practice of deep well dewatering, sinking correction, and nesting pile of caisson in high sensitivity soil. By choosing scientific and reasonable scheme from different research, the protection technology of caisson nested piles in high sensitivity soil has been contrived. The study results has been applied to the construction of the circulating water pump station in river bank or coastal area where there is high sensitivity soil, with not only a high construction speed but a lower price.2. This thesis investigates the construction technique of obstacle clearance with gas in shield tunnel and this technique has been applied to the project of the CHINA HUANENG Jingling power plant, solving the difficulty of the shield tunnel crossing river rock subsidence area.3. Integrating the earth pressure balance shield, The new Austrian Tunneling Method and obstacle clearance technology,for the first time, this new integrating technique is used in construction, making the shield machine smoothly go through the complex formation and completing the first large diameter shield tunnel in china nuclear power field.4. This thesis focuses on research and development of large diameter vertical jacking construction techniques and equipment by analyzing the development trend of water intake structure of large-scale power plants. And this technique has been applied to the first phase of the sandmen nuclear power plant project.The research harvest on construction techniques including deep well dewatering techniques, sinking correction techniques, the protection technology of caisson nested piles, the integrating of the earth pressure balance shield and the new Austrian Tunneling Method, obstacle clearance technology, and large diameter vertical jacking construction techniques, involved in the paper all has been successfully applied in engineering, which can provide reference for future similar project.