【作者】 贺汇文；

【导师】 苏生瑞；

【作者基本信息】 长安大学 ， 地质工程， 2009， 博士

【摘要】 秦岭山区是变质岩分布广泛、出露较全的典型地区。变质岩地区岩体的特殊性质，对公路边坡的稳定性构成不同程度的影响，制约着公路的施工与安全运营。分析变质岩地区边坡变形破坏的主控因素，查明变质岩边坡岩体变形破坏机制和可能的破坏方式，提出稳定性评价方法，对制订合理的边坡设计与处治方案以及有效地防治边坡地质灾害，具有重要的理论意义和实用价值。本文以秦岭变质岩地区公路边坡岩体结构特征研究为出发点，以大地构造学、变质岩岩石学、岩体结构理论为主线，采用现场调查、室内与现场试验、理论分析和数值模拟相结合等方法，对秦岭山区变质岩体岩体结构特征及公路边坡稳定性进行了系统的研究。取得的主要研究成果如下：(1)运用大地构造学的理论与方法，对秦岭变质岩岩体的沉积建造、变形-变质和后期改造进行了研究，提出了变质岩岩体物质受秦岭地槽的演化控制体系，认为陆内造山运动是岩体变质—变形的重要过程，是控制岩体结构的基本形式，为进一步分析变质岩边坡岩体结构特点奠定基础。(2)运用变质岩岩石学研究理论，借助岩矿鉴定对秦岭地区变质岩的特征进行了研究，将秦岭变质岩按照岩相、结构及基本力学性质归纳为4大类12亚类岩组。(3)在现场地质调查的基础上，从岩体结构与工程地质意义出发，对变质岩体结构面按照区域规模进行了系统分级，共分为5个级别，并对边坡稳定性起控制作用的Ⅲ、Ⅳ级结构面特征进行了详细的研究，认为结构面的分布规律和赋存状态是变质岩边坡结构的重要影响因素。(4)在对结构面、结构体进行系统研究的基础上，针对变质岩岩体边坡的特点提出了变质岩边坡的岩体结构分类，共分为4大类9个亚类，其中最为普遍的是层状结构和散体结构类型。(5)首次对秦岭变质岩区发育的糜棱岩化千枚岩的物理力学性质进行了系统的物理力学试验研究，得到了岩石的全应力应变曲线，并分析了岩石变形破坏的类型与机理，获得了糜棱岩化千枚岩的变形与力学参数。结果表明，变质岩的力学性质受变质过程中岩石微结构的影响明显，测试结果离散度大，平行与垂直面理方向力学性质差异较大。(6)归纳总结了变质岩公路边坡变形破坏的分布规律和影响因素。通过对秦岭地区大量的公路边坡调查分析，结合变质岩公路边坡岩体结构、坡体结构、岩石组合特征以及风化特征等，在详细分析边坡变形破坏影响因素的基础上，提出了系统的变质岩公路边坡变形破坏模式。(7)在系统总结变质岩区边坡岩性、岩体结构、边坡角、破坏模式等后，提出变质岩区公路边坡的综合评价标准。以典型变质岩公路边坡的稳定性进行分析为例，采用结构分析、定量评价以及应力—应变分析的方法，建立了变质岩公路边坡稳定性分析-计算的技术思路。更多还原

【Abstract】 Qinling Mountains is a typical place where metamorphic rocks are widely distributed. The special nature of the metamorphic rocks has affected the stability of the slope and restricted the construction and safe operations of highway. Analyzing the main control factors of slopes in the metamorphic rocks area, identifying the rock deformation and failure mechanism, and possible failure mode, and presenting the evaluation method of the stability have important theoretical significance and practical value for reasonable slope designing and treatment programs, and effective prevention of geological disasters in the slopes. In this thesis, regarding rock structure research of highway slope in Qinling metamorphic rocks as the starting point, with the main line of geotectonics, metamorphic petrology and rock structure theory, the author analyzed systematically development features of metamorphic rocks structure, mechanical properties and failure mechanisms of metamorphic rocks, deformation and failure model of metamorphic rocks and the stability of slopes by using the methods of the site geological survey, laboratory testing, theoretical analysis and numerical simulation.The main research results are as follows:(1) The author studied sedimentary formation, deformation—deterioration and post-transformation of metamorphic rocks mass in the Qinling orogenic belt with geotectonics, proposed controlling system of metamorphic rocks mass to Qinling geosyncline and found that inland orogeny is the important process of rock mass deformation and the basic form of controlling rock mass structure, which laid a foundation for the further research on rock mass structure characteristics of metamorphic rocks slope.(2) The author studied characteristics of metamorphic rocks in Qinling with metamorphic petrology and rock and mineral identification. Metamorphic rocks in Qinling are divided into four categories of twelve sub-types of rock group by lithofacies, structure and basic mechanical properties through investigations.(3) On the basis of site geological survey, from the significance of the rockmass structure and engineering geology, metamorphic rock mass structure is divided into five levels by the scale of region. Also, the author made a detailed study of level III and IV structure features which has a direct controlling influence to the stability of slope, and thought that the structural distribution and occurrence is the important influence factor of metamorphic rock slope structure.(4) Based on the research of the discontinuity and structural body, rock mass structure of metamorphic rock slope is divided into four categories of nine sub-types, in which the most common are layered structure and loose structure, according to the characteristics of metamorphic rock slope.(5)The thesis made a systematic tests study on physical and mechanical properties of mylonitize phyllite developed in Qinling metamorphic rocks zone for the first time and got the complete stress-strain curve. Also, the author analyzed the types and mechanism of rock deformation and failure, and obtained deformation and mechanical parameters of mylonitize phyllite. It is showed that rock microstructure formed metamorphism has significant influence on the mechanical properties of the metamorphic rocks, the discrete test results, and the widely different between mechanical properties parallel to foliation and perpendicular to foliation.(6) The author summarized the distribution and influence factors on deformation and failure of highway slope in metamorphic rocks. Through a large number of survey and analysis of the slope in Qinling, a systemic deformation and failure model of metamorphic rock is proposed, based on a detailed analysis of the influence factors on slope deformation and failure, combining rock mass structure characteristics of highway slope in metamorphic rocks, slope structure, rock association and weathering features.(7) After a systematic summary of lithology, rock structure, slope angle, and the failure mode etc. in the slope, a comprehensive evaluation standard is proposed. Taking the stability analysis on typical highway slope in metamorphic rocks for example, the author puts forward technical strategy and methodological system on the stability analysis and calculation of highway slope in metamorphic rocks by using the methods of structural analysis, quantitative evaluation and stress-strain analysis.更多还原