Abstract：An improved ubiquitous-joint constitutive model(Transverse Isotropic Elasto-Plastic Ubiquitous-Joint model)，which can take into account both the strength anisotropy and the deformation anisotropy of phyllite，was developed in FLAC3D，and a formula for analyzing elastic deformation anisotropy of transversely isotropic materials was derived. Furthermore，the excavation of the tunnel with steeply dipping phyllite strata was simulated，the corresponding destruction mechanism was revealed and the validity of this model was verified. The results reveal that the tunnel surrounding rock is very prone to shear failure along the weak plane due to the low shear strength of the weak plane and that the tunnel surrounding rock of the tunnel outline parallel to the weak plane is prone to tension failure at which the tunnel outline is parallel to the weak plane because of the low tensile strength of the weak plane. The concentration of the compressive stress can lead to the shear failure of the rock matrix while the tensile failure of the rock matrix does not occur in the process of tunnel excavation. Under the influence of deformation anisotropy of phyllite，the displacement field of the surrounding rock shows obvious asymmetry. A larger ratio of the horizontal stress to the vertical stress will result in compression deformation of the surrounding rock towards the tunnel，which is the main reason for the failure of the supporting structure. The research results in the paper can provide a useful reference for similar projects.
BORESI A P，LYNN P P，HUNG Y Y. Elasticity in engineering mechanics[M]. 3rd ed. New Jersey：Wiley，2011：241-248.
[16]
REDDY J N. Mechanics of laminated composite plates and shells theory and analysis[M]. 2 ed. New York：CRC Press，2004：81-106.
[4]
RAMAMURTHY T，RAO G V，SINGH J. Engineering behaviour of phyllites[J]. Engineering Geology，1993，33(3)：209-225.
[2]
TIEN Y M，TSAO P F. Preparation and mechanical properties of artificial transversely isotropic rock[J]. International Journal of Rock Mechanics and Mining Sciences，2000，37(6)：1 001-1 012.
[6]
XU G，HE C，SU A，et al. Experimental investigation of the anisotropic mechanical behavior of phyllite under triaxial compression[J]. International Journal of Rock Mechanics and Mining Sciences，2018，104：100-112.
[7]
吴永胜，谭忠盛，余贤斌，等. 龙门山北段千枚岩强度及变形特性对比试验研究[J]. 岩土工程学报，2017，39(6)：1 106-1 114.(WU Yongsheng，TAN Zhongsheng，YU Xianbin，et al. Comparative tests on strength and deformation of phyllite of northern tunnels of Longmen Mountains[J]. Chinese Journal of Geotechnical Engineering，2017，39(6)：1 106-1 114.(in Chinese))
场对比试验研究[J]. 岩石力学与工程学报，2017，36(3)：609-621.(XU Fei，LI Shucai，SHI Shaoshuai，et al. Field test comparison of traditional and new type supporting structures in a phyllite tunnel[J]. Chinese Journal of Rock Mechanics and Engineering，2017，36(3)：609-621.(in Chinese))
[13]
李 磊，谭忠盛，喻 渝，等. 成兰铁路千枚岩隧道初期支护形式试验研究[J]. 土木工程学报，2017，50(增1)：19-24.(LI Lei，TAN Zhongsheng，YU Yu，et al. Experimental study on primary lining form of tunnels in phyllite on Chengdu-Lanzhou railway[J]. China Civil Engineering Journal，2017，50(Supp.1)：19-24.(in Chinese))
[15]
朱泽奇，盛 谦，梅松华，等. 改进的遍布节理模型及其在层状岩体地下工程中的应用[J]. 岩土力学，2009，30(10)：3 115-3 121. (ZHU Zeqi，SHENG Qian，MEI Songhua，et al. Improved ubiquitous-joint model and its application to underground engineering in layered rock masses[J]. Rock and Soil Mechanics，2009，30(10)：3 115-3 121.(in Chinese))
[18]
陈明祥. 弹塑性力学[M]. 1版. 北京：科学出版社，2013：246- 285.(CHEN Mingxiang. Elasticity and plasticity[M]. 1st ed. Beijing：China Science Publishing and Media Ltd.，2013：246-285.(in Chinese))
[5]
HAKALA M，KUULA H，HUDSON J A. Estimating the transversely isotropic elastic intact rock properties for in situ stress measurement data reduction：a case study of the Olkiluoto mica gneiss，Finland[J]. International Journal of Rock Mechanics and Mining Sciences，2007，44(1)：14-46.
[8]
郭小龙，谭忠盛，李 磊，等. 高地应力陡倾层状软岩隧道变形破坏机制分析[J]. 土木工程学报，2017，50(增2)：38-44.(GUO Xiaolong，TAN Zhongsheng，LI Lei，et al. Deformation and failure mechanism of layered soft rock tunnel under high stress[J]. China Civil Engineering Journal，2017，50(Supp.2)：38-44.(in Chinese))
[14]
SHI X，YANG X，MENG Y，et al. An anisotropic strength model for layered rocks considering planes of weakness[J]. Rock Mechanics and Rock Engineering，2016，49(9)：3 783-3 792.
[10]
HU K，FENG Q，WANG X. Experimental research on mechanical property of phyllite tunnel surrounding rock under different moisture state[J]. Geotechnical and Geological Engineering，2017，35(1)：303-311.
[19]
Itasca Consulting Group Inc.. FLAC3D 3.0 manual[R]. Mineapolis，Minnesota，USA：[s. n.]，2005.
[1]
FORTSAKIS P，NIKAS K，MARINOS V，et al. Anisotropic behaviour of stratified rock masses in tunnelling[J]. Engineering Geology，2012，141/142：74-83.
[3]
NASSERI M H B，RAO K S，RAMAMURTHY T. Anisotropic strength and deformational behavior of Himalayan schists[J]. International Journal of Rock Mechanics and Mining Sciences，2003，40(1)：3-23.
[11]
徐 飞，李术才，石少帅，等. 千枚岩隧道传统与新型支护结构现
[12]
李 磊，谭忠盛，郭小龙，等. 挤压陡倾千枚岩地层小净距隧道大变形研究[J]. 岩石力学与工程学报，2019，38(2)：276-286.(LI Lei，TAN Zhongsheng，GUO Xiaolong，et al. Research on large deformation of tunnel with small interval in squeezing steeply dipping phyllite strata[J]. Chinese Journal of Rock Mechanics and Engineering，2019，38(2)：276-286.(in Chinese))
[20]
李 磊，谭忠盛，郭小龙，等. 高地应力陡倾互层千枚岩地层隧道大变形研究[J]. 岩石力学与工程学报，2017，36(7)：1 611-1 622.(LI Lei，TAN Zhongsheng，GUO Xiaolong，et al. Large deformation of tunnels in steep dip strata of interbedding phyllite under high geostresses[J]. Chinese Journal of Rock Mechanics and Engineering，2017，36(7)：1 611-1 622. (in Chinese))
[9]
JAEGER J C. Shear failure of anisotropic rocks[J]. Geological Magazine，1960，97(1)：65-72.
2019, Vol. 38 
