高放废物地质处置库备选黏土岩温度-渗流-应力耦合长期力学特性研究

Deep geological disposal is the only technically feasible way of permanent disposal of high-level radioactive waste until now. As the suitable properties of low permeability, good creep and self-healing characteristics under the influence of water, claystone is considered as a potential permanent storage medium for geological disposal of high-level and long-lived radioactive nuclear wastes. Take the claystone, in the primary zone where the high-level radioactive waste wanted to be disposed in future in China, as the research object, the proposed project aims at studying the long-term creep THM coupled behaviour of claystone with focus on the temperature effect on the creep and permeability self-sealing capacity under THM coupled cases, and THM coupled elasto-plastic damage constitutive model, nonlinear creep mechanical model and anistroptic permeability self-sealing model will be established. Based on a series of tests,containing THM coupled triaxial tests, creep tests, permeability self-sealing tests and the conceptual model of the high level radioactive nuclear waste geological storage, back analysis will be performed thanks to these valuable data and the material parameters in the theoretical model above will be obtained. Finally, long-term THM coupled creep behavior of waste repository will be done in 3D numerical model. Research results will provide the theoretical guidance for the long-term safety assessment of the high-level radioactive waste geological disposal, underground energy storage and other major projects in China.

深层地质处置是世界普遍认为技术上唯一可行的高放废物永久处置方法，黏土岩由于其低渗透性、良好的蠕变性、强吸附性和裂隙遇水损伤自闭合等特性被认为是一种理想的核废料储存介质。本课题以我国高放废物地质处置预选区黏土岩地层为研究对象，研究THM耦合作用下黏土岩长期力学特性及其裂隙渗透损伤演化至自闭合的机理，建立黏土岩THM耦合作用下弹塑性损伤流变模型和裂隙渗透损伤演化自闭合模型，提出相应的数值仿真方法。并针对我国高放废物处置库概念地质模型，应用建立的黏土岩THM耦合非线性力学模型和渗透损伤自闭合模型预测处置库围岩的长期变形破坏特征和渗流演化规律。研究成果将为我国未来高放废物黏土岩地质处置库长期安全性评估提供可靠的试验数据和重要依据。

深层地质处置是世界普遍认为技术上唯一可行的高放废物永久处置方法，黏土岩由于其低渗透性、良好的蠕变性、强吸附性和裂隙遇水损伤自闭合等特性被认为是一种理想的核废料储存介质。本课题以我国高放废物地质处置预选区黏土岩地层为研究对象，研究THM耦合作用下黏土岩长期力学特性及其裂隙渗透损伤演化至自闭合的机理，建立黏土岩THM耦合作用下弹塑性损伤流变模型和损伤演化方程，提出相应的数值仿真方法。并针对我国高放废物处置库概念地质模型，应用建立的理论模型预测处置库围岩的长期变形破坏特征和渗流演化规律。研究成果将为我国未来高放废物黏土岩地质处置库长期安全性评估提供可靠的试验数据和重要依据。