On Oct. 9, 2021, the Administrative Center for China’s Agenda 21 organized an overall performance evaluation meeting in Nanjing for the project of Key Technologies for Construction and Long-term Security of Ultra-high Earth-rock Dam in Complex Conditions under a key special project of the National Key R&D Program, Efficient Development and Utilization of Water Resources, led by NHRI. Leaders from the Department of International Cooperation, Science and Technology, Ministry of Water Resources (MWR), China and the National Key Project Management Office of NHRI, and NHRI President CHEN Shengshui attended the meeting. The meeting saw the attendance of more than 40 people, including project leader, subject leaders and technical backbones from Wuhan University, Tsinghua University, China Institute of Water Resources and Hydropower Research, Changjiang Institute of Survey, Planning, Design and Research, and MWR General Institute of Water Resources and Hydropower Planning and Design.
After the report on the project implementation by project leader CHEN Shengshui, professor-level senior engineer, and reviews, inquiries and discussions of relevant documents, the expert panel unanimously agreed that the fundamental theories and technical research and development achievements of the project were of prominent innovation, with a high degree of integrated application, good application effects, broad prospects of promotion, and expected goals of the project achieved, making a positive contribution to the objectives of the key special project of Efficient Development and Utilization of Water Resources. The panel agreed that the project passed the overall performance evaluation.
Over the last 4 years, the multi-scale experimental technologies and equipment for the strength, deformation and seepage features of coarse-grained soils in ultra-high dams have been researched and developed by the project, oriented to the construction and long-term security requirements of ultra-high earth-rock dams over 200m in complex conditions. The coarse-grained soil constitutive theory, the calculation theory and method of deformation and failure process of various contact problems and the calculation method of seepage-induced failure process have been established to correctly reflect the deformation and failure mechanism of ultra-high earth-rock dams. The disaster prevention and control techniques and measures for ultra-high earth-rock dams have been researched and developed regarding complex construction and operation conditions, such as narrow river valley, deep overburden layer of dam foundation and extremely cold weather. Based on a national safety monitoring and supervision platform for large reservoir dams in China, a decision support system for long-term security of ultra-high earth-rock dams has been constructed through the integration of the project’s achievements with the main contents of "prediction and evaluation, safety standardization, safety monitoring, prevention and control technology".
The project achievements have been applied in pilot engineering, such as the completed Altash concrete face sand gravel dam (max. dam height of 164.8m and thick overburden layer of 97m), the Dashixia concrete face sand gravel dam (max. dam height of 247m), the highest dam in the world under construction and RM gravel-clay soil core rock-fill dam in design, with remarkable economic and social benefits.