The research and practice of major technological issues on design of Three Gorges Project

The dam of Three Gorges Project is characterized by large flood discharge capacity,more outlets,complicated flood discharge and energy dissipation structure,and the stability of the bank powerhouse dam foundation is endangered by large gentle-dip structural plane of the bedrock due to the deep excavation of powerhouse at the dam-toe.For the dam body concrete,the durability requirement is high and the temperature control and crack prevention are difficult.The practical experience which could be used for reference in the design and construction of asphalt concrete core wall for Maopingxi protective earth-rock dam is scarce.The power station operates with high water head and large head variation.The type selection of penstock and intake as well as the embedding way of spiral case are complicated in technique,and the tailrace tunnel with sloping ceiling of underground power plant is arranged instead of traditional tailrace surge tank.For the double-line five-step ship-lock,the design of fully lined ship-lock,high head delivery system and large-sized miter gates and hoists is very challenging due to high operation head,complicated delivery conditions and building in deep excavated rock.The preferred solutions,optimal schemes and technical measures for various structures,as well as the innovation achievements proved by practice are highlighted.

Commentary of research situation and innovation frontier in hydro-structure engineering science

In order to utilize water and hydropower resources in China,multitudes of water projects are established or to be constructed as an integral part of the national economy's infrastructure.Under these circumstances,there are two outstanding problems:1) a mass of existing dams are in danger and 2) in the southwest water-conservancy construction plan,dozens of existing or planned dams are high dams or even super high dams with heights between 200 and 300 m.In accordance with demands of "the National Program for Medium-and Long-Term Scientific and Technological Development" on the innovation frontier in hydro-structure engineering science,various key problems in science and technology such like stress analysis,ultimate bearing capacity,nonlinearity etc.for high dams,super high dams and sick dams have been investigated.This paper makes a commentary on the advances and results of the researches,then analyzes the advantages and disadvantages of current theoretics and methodologies,and finally presents corresponding research directions and the frontier of innovation.