深部软岩大型三轴压缩流变试验及本构模型研究

 岩体三向应力状态下的三轴流变试验是真实反映工程岩体流变特性的重要手段。详细介绍泥岩现场大型真三轴蠕变试验过程、方法和试验成果，深入分析蠕变变形随时间的变化规律，提出泥岩非线性经验幂函数型蠕变模型及其参数，该模型真实地反映了深部软岩不同应力水平下的流变特征。研究结果表明，泥岩的蠕变速率不仅与时间密切相关，还与应力水平相关。研究成果可用于软岩工程巷道的长期变形预估和支护设计，对软岩巷道的支护优化设计具有重要的参考价值。

RESEARCH ON LARGE-SCALE TRIAXIAL COMPRESSIVE RHEOLOGICAL TEST OF SOFT ROCK IN DEPTH AND ITS CONSTITUTIVE MODEL

The in-situ rheological test under three-dimensional stress is a very useful way to reflect the actual rheological properties of filed rock mass. The test process，method and results of in-situ large-scale true triaxial test are presented. Variation law of deformation with time is further analyzed；and the experimental curve is described using a nonlinear kinetic creep model. Then，the theoretical rheological equation is established；each parameter of creep model is obtained and the rheological characteristics of deep soft rock are well reflected. The results show that the creep rate of mudstone is not only related to stress state，but also to time. The results can be applied to the estimation of long-term deformation of engineering tunnel in soft rock engineering and design of support，which have important reference values to the optimization design of tunnel support of soft rock.