Abstract: In order to study the anisotropic properties of Danba schist, the field triaxial loading and unloading tests were implemented firstly. Based on the test results of specimen strength and deformation parameters, a numerical model was built for the uniaxial or triaxial compression test with the UDEC. The main objective of this study was to investigate the anisotropy of Danba schist on strength and deformability by simulating a series compression tests with series schistosity angle. Followed, based on the previous research, an excavation process of typical tunnel was analyzed in detail. Comparison between the numerical calculation results and the field test data showed that the responses were slightly different. The analysis result indicated that rock strength and deformation properties were noticeably dependent on schistosity, and the schist anisotropy can have a significant impact on the failure behavior of tunnel surrounding rock. Objectively speaking, by UDEC analysis, the anisotropy characteristics of Danba schist can be reflected, however, some complex mechanics should be studied in the future.

Key words: quartz-mica schist, anisotropy, UDEC, numerical simulation

摘要： 为研究丹巴石英云母片岩的各向异性特性，首先开展了工程现场三轴加卸载试验，并获得了较大尺度试件的强度和变形各向异性参数。基于现场试验结果，采用UDEC建立数值加载模型，重点考察了片理对片岩各向异性的作用机理，研究了不同片理方向加载时岩体的强度和变形各向异性特征。之后针对实际工程进行模拟，分析了考虑岩体各向异性特征情况下隧洞围岩的变形破坏机制，并通过对比现场测试成果，探讨了该分析方法的实用性。研究表明，基于UDEC的分析思路和方法能反映丹巴石英云母片岩的各向异性特点，但某些复杂特性还有待进一步研究。

关键词: 石英云母片岩, 各向异性, UDEC, 数值模拟