高放废物地质处置库围岩各向异性热-水-力耦合机理及长期安全性分析

项目名称： 高放废物地质处置库围岩各向异性热-水-力耦合机理及长期安全性分析

项目编号： No.51479193

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 水利工程

项目作者： 胡大伟

作者单位： 中国科学院武汉岩土力学研究所

项目金额： 84万元

中文摘要： 围岩中原生节理和开挖扰动区内次生裂纹引起的各向异性热-水-力耦合是控制高放废物地质处置库长期安全性的关键因素，对热、水和力三场耦合的各向异性的系统研究还不多见。本项目从其内在机理：原生裂隙和次生裂纹出发，设计了一系列含裂隙试样和破坏后产生裂纹的试样的室内试验，获得轴向和侧向方向上的弹性模量、有效应力系数、热传导系数和热膨胀系数以及渗透系数等的演化规律，分析原生裂隙和次生裂纹中热、水和力三场之间的相互作用，建立花岗岩各向异性热-水-力耦合模型。采用热-水-力耦合作用下裂隙和破坏后试样的流变试验模拟实际围岩结构，对所建立的模型进行验证和改进。采用扩展有限元的方法，提出处置库各向异性热-水-力耦合数值分析方法，对我国高放废物地质处置库的长期稳定性和核素迁移性在热-水-力耦合作用下的长期演化特征进行研究。研究成果可为处置库的选址、设计和稳定性分析提供关键的理论和技术支持。

中文关键词： 热-水-力耦合；各向异性；高放废物地质处置；长期安全性

英文摘要： The anisotropic thermo-hydro-mechanical coupling behavior caused by original joints and indeuced cracks in sorrounding rock is the controlling factor of the long term safety of high-level radioactive waste underground repositories, while its mechanism is still lack of qualitative knowledge. From the viewpoint of its physical reason: original joints and induced cracks, the systemic methods including laboratory tests, theoretical model and extended finite element are used in this project. A series of laboratory tests are proposed to perform on the samples with original joints and induced cracks in order to obtain the evolutions of elastic modulus, effective stress coefficient, thermal conductivity, thermal expansion coefficient and permeability in both axial and lateral directions. The anisotropic thermo-hydro-mechanical coupling model is formulated based on the interaction mechanism of temperature, flow and stress. The creep tests on the samples with original joints and induced cracks under the effect of thermo-hydro-mechanical coupling are used to model the in situ surrounding rock structure and verify the proposed model. Extended finite element method is used to construct numerical algorithm of thermo-hydro-mechanical coupling, the long term safety and nuclide migration of high-level radioactive waste underground repositories under thermo-hydro-mechanical coupling effect is analyzed. The studied results can offer important theoretic and technical support for site choice, safety design and stabilization analysis of radioactive waste underground repositories in China.

英文关键词： thermo-hydro-mechanical coupling;anisotropic;high-level radioactive waste underground repository;long term safety