Abstract It is necessary to apply reliable numerical simulation techniques to assess the mechanical behavior of repositories for the long-term geological disposal of radioactive waste. Having a constitutive model that can describe the mechanical behavior of bentonite is key to such numerical simulations. In this study, the applicability of a linear-elastic constitutive model with a swelling term is examined, focusing on density heterogeneity of the in-situ full-scale engineered barrier experiment (FEBEX) in Grimsel. It was found that the constitutive model underestimates the density change. Therefore, the mechanical behavior was re-simulated with an unsaturated elasto-plastic constitutive model using the changes in degree of saturation as input data. Two-dimensional stress and dry density was reproduced.

中文翻译：

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非线性弹性行为对 FEBEX 膨润土密度演变的影响

摘要 有必要应用可靠的数值模拟技术来评估放射性废物长期地质处置处置库的力学行为。拥有可以描述膨润土力学行为的本构模型是此类数值模拟的关键。在这项研究中，研究了具有膨胀项的线弹性本构模型的适用性，重点是 Grimsel 中原位全尺寸工程屏障实验 (FEBEX) 的密度异质性。发现本构模型低估了密度变化。因此，使用饱和度的变化作为输入数据，使用不饱和弹塑性本构模型重新模拟机械行为。再现了二维应力和干密度。