Management of energy waste such as high-level waste (HLW) disposal in deep geological repositories is one of most pressing challenges in the context of nuclear energy. The general research question addressed in the present work is how to represent coupled physical processes after the emplacement of heat-emitting waste in such a repository in claystone at multiple scales by numerical models and how can they validated by experimental results in underground research laboratories. Numerical modelling of the coupled thermal hydraulic mechanical (THM) processes to assess the long-term safety of deep geological repositories rests on adequate constitutive laws and quantification of in-situ host rock material properties during long-term heating as well as a reliable numerical approach for solving the underlying governing equations. For this purpose, various in-situ experiments have been conducted in the Callovo-Oxfordian claystone (COx) at the Meuse/Haute-Marne (M/HM) Underground Research Laboratory (URL) by the French National Radioactive Waste Management Agency (ANDRA) since 2003. A subset of these is investigated here using a numerical THM model employed at different spatial scales. Two main results were achieved. First, the previously developed numerical THM model (Wang et al., 2021) has been compared agains in-situ experimental data from the full-scale heating (ALC) experiment at the M/HM URL in an attempt to validate the model. The numerically simulated temperature and pore pressure data of the ALC experiment are in good agreement with in-situ measured data. This model was then employed to simulate fully coupled THM processes of an entire repository section for High-Level Waste (HLW) in a COx clay formation according to the Cigeo project by ANDRA. This upscaling was enabled by running the numerical code on high-performance-computing platforms. Three-dimensional, fully coupled and efficient THM models for the numerical simulation of deep geological repositories such as the one presented in this study will help in the design of nuclear waste repositories under realistic geological conditions. Moreover, the present work is a contribution to Task E of the DECOVALEX-2019 project for model validation and comparison against experimental results (Plúa et al., 2021; Seyedi et al., 2020).

在深层地质处置库中处理高放废物 (HLW) 等能源废物管理是核能背景下最紧迫的挑战之一。当前工作中解决的一般研究问题是如何通过数值模型在多尺度的粘土岩中放置发热废物后的耦合物理过程，以及如何通过地下研究实验室的实验结果对其进行验证。用于评估深层地质储层长期安全性的耦合热力水力机械 (THM) 过程的数值模拟取决于长期加热过程中适当的本构规律和原位围岩材料特性的量化以及可靠的数值方法用于求解基本的控制方程。以此目的，自 2003 年以来，法国国家放射性废物管理局 (ANDRA) 在默兹/上马恩 (M/HM) 地下研究实验室 (URL) 对 Callovo-Oxfordian 粘土岩 (COx) 进行了各种原位实验。这里使用在不同空间尺度上采用的数值 THM 模型来研究这些子集。取得了两个主要成果。首先，之前开发的数值 THM 模型（Wang 等人，2021）已与 M/HM URL 处全尺寸加热 (ALC) 实验的原位实验数据进行了比较，以尝试验证模型。ALC实验的数值模拟温度和孔隙压力数据与现场实测数据吻合较好。然后，根据 ANDRA 的 Cigeo 项目，该模型用于模拟 COx 粘土地层中高放废物 (HLW) 的整个处置库部分的完全耦合 THM 过程。这种升级是通过在高性能计算平台上运行数字代码实现的。用于深地质处置库数值模拟的三维、完全耦合和高效的 THM 模型，例如本研究中提出的模型，将有助于在现实地质条件下设计核废料处置库。此外，目前的工作是对 DECOVALEX-2019 项目的任务 E 的贡献，用于模型验证和与实验结果的比较（Plúa 等人，2021 年；Seyedi 等人，2020 年）。这种升级是通过在高性能计算平台上运行数字代码实现的。用于深地质处置库数值模拟的三维、完全耦合和高效的 THM 模型，例如本研究中提出的模型，将有助于在现实地质条件下设计核废料处置库。此外，目前的工作是对 DECOVALEX-2019 项目的任务 E 的贡献，用于模型验证和与实验结果的比较（Plúa 等人，2021 年；Seyedi 等人，2020 年）。这种升级是通过在高性能计算平台上运行数字代码实现的。用于深地质处置库数值模拟的三维、完全耦合和高效的 THM 模型，例如本研究中提出的模型，将有助于在现实地质条件下设计核废料处置库。此外，目前的工作是对 DECOVALEX-2019 项目的任务 E 的贡献，用于模型验证和与实验结果的比较（Plúa 等人，2021 年；Seyedi 等人，2020 年）。