A study on flow-deformation coupled behavior in an excavation disturbed zone and development of analysis method for the behavior

在日本，计划将高放射性废物和TRU废物处置在稳定的岩石中。至于高放废物问题，有必要确保残留的放射性物质在几千年后不会到达生物圈。因此，不仅可以预测力学行为，而且可以长期预测水力行为的数学模型是至关重要的。不连续岩体的力学性质和水力性质分别具有很强的相关性。本文利用人工试件进行了静力试验和蠕变试验，探讨了土体的力学行为和水力学行为机理。每个测试包括两种类型的样本，一种包括不连续点，另一种不包括不连续点。所有试验都是在不同的围压和不同形状的不连续面下进行的。此外，还对蠕变试验中的耦合行为进行了数值分析。首先，提出了考虑结构面变形的蠕变模型。数值计算结果与实测数据有较好的一致性。通过实验和分析的对比，对耦合行为的机理进行了探讨。结果表明，所提出的分析模型是比较有效的，可以用来估计核废料处置隧道周围开挖扰动带(E.D.Z)中不连续岩体的长期行为。

In Japan, it is planned to dispose high-level radioactive waste and TRU waste in a stable rock mass. As for the HLW problems, it is necessary to ensure that residual radioactive substances are kept from reaching the biosphere after many thousands of years. Thus the mathematical model by which not only mechanical but also hydraulic behaviors can be predicted for a long-term is of prime importance. The mechanical and hydraulic properties of discontinuous rock mass have strong correlations respectively. In this study, a static test and a creep test with associated to the coupled behaviors are conducted with the use of an artificial specimen so as to seize the mechanism of the mechanical and hydraulic behaviors. Each test consists two type of specimen, one includes a discontinuity and the other does not have it. All tests are conducted under various confining pressures and various shapes of the discontinuity. Moreover, the numerical analysis by which the coupled behavior in the creep test is reproduced is carried on. Above all, the creep model that takes into account the deformation of discontinuity is proposed. The numerical result has modestly good accordance with the measured data. From the comparison of the experiment and the analysis, the mechanism of coupled behavior is discussed. In results, the proposed analysis model is modestly effective and can be utilized to estimate a long-term behavior of a discontinuous rock mass in an excavation disturbed zone (E.D.Z) around a disposal tunnel for nuclear wastes.