放射性废物地质处置中主要岩石力学问题

MAIN ROCK MECHANICS ISSUES IN GEOLOGICAL DISPOSAL OF RADIOACTIVE WASTES

放射性核废物的地质处置是一个关系到国计民生多学科交叉的综合性问题。它不仅提出了许多挑战性的科学和技术课题,而且在一个更高的层面上对国家核能、核废物、国防和环境保护事业中大型科学研究的总体规划和组织实施、经费保障及工程建设等提出了立法和政策方面的要求。岩石力学和岩石工程是放射性废物地质处置问题的一个极其重要的方面。放射性废物地下处置系统的设计、现场址质调查、工程设计和施工、运行以及系统长期安全性评估均含有重要的岩石力学和岩石工程内容,因而在放射性废物地质处置的研究和发展规划中有不可取代的地位。据此,首先对核废物地质处置的总体系统及各个主要环节的主要理论和工程问题作一个简要的介绍。然后在此基础上,提出在可行性研究及现场勘查调研对岩石力学和岩石工程主要内容、要求及目前国际上的动态和发展方向。讨论的重点是节理岩体的温度、应力、流体流动及化学反应过程耦合效应的数值方法、试验研究,及其国际放射性废物处置事业中的进展和前景及中国在核废物地质处置方面所开展的研究工作以及所取得的进展。

Geological disposal of radioactive wastes is a multi-disciplinary issue of importance for national interest. It stimulated many challenging scientific and technical issues, and at a higher level, presented a series of demanding requirements for a country＇s overall research and development programme, its implementation and engineering practice, about basic policies and legislature concerning nuclear energy, defense, waste management and environment. Rock mechanics and rock engineering are very important fields for geological disposal of ：radioactive wastes, and contribute significantly to the conceptual design, site investigation, engineering design and construction, operation and the long-term safety assessment of the waste repositories. It plays, therefore, a irreplaceable role in the research and development programme of geological disposal of radioactive wastes. In this paper, we first summarizes briefly the main steps about repository system, followed by the major demands for rock mechanics and rock engineering during feasibility study and site investigation, and the major international trends concerning these issues. The focus is placed on the coupled thermo-hydro-mechanical and chemical（THMC） processes and the current status of research in international communities. At the end, the progresses in research and development works in the field of radioactive waste disposal in China are presented; and possible future working directions are discussed.