【作者】 唐胜传；

【导师】 黄润秋；

【作者基本信息】 成都理工大学 ， 地质工程， 2002， 博士

【摘要】 研究复杂地质环境条件下高坝建设的适宜性是水电工程建设过程中不可或缺的一个重要环节。针对这一课题，本文较为系统和明确的提出了高坝建设的适宜性评价问题以及研究这一问题的基本原理与方法体系。在此基础上，以澜沧江糯扎渡水电站为研究对象，以大量的现场实测资料为基础，以GEMM(Geology-Engineering-Mechanic Model)模型为桥梁，结合系统的数值模拟分析，进行了复杂场地高坝建设适宜性的工程地质研究。研究内容包括了岩体结构、地应力场、岩体力学特性、水力学特性等岩体力学环境条件的分析和评价；重点阐述了与高坝建设适宜性评价有关的岩体质量分级、GEMM模型建立及不同坝型在修建过程中可能产生的边坡稳定性问题、坝基不均匀沉降问题以及在蓄水后坝基岩体的变形稳定性问题。通过上述研究，本文取得了如下主要成果： 系统归纳、总结了高坝建设工程地质适宜性评价的理论和方法，并将整个适宜性评价划分为规划选点、坝段坝址比选、坝线坝型比选、专项工程地质研究和技施设计工程地质研究五个阶段，提出了各个阶段的适宜性评价目标和决定因素。整个高坝建设适宜性评价的过程是一个从仅仅考虑地质因素到综合考虑地质环境和工程相互作用的逐步深入过程。 提出了GEMM模型的概念，将GEMM模型定义为：由等价体单元、界面单元(包括天然边界单元和人工边界单元)以及各地质单元的目标参数构成的，包含有关键工程信息并可直接应用于分析判断和数值计算的参数化模型。认为GEMM模型是整个高坝建设工程地质适宜性评价的核心和纽带，它既是地质条件的概化综合，又包含了地质环境和工程相互作用的关键信息，同时也是理论分析和数值计算的基础。 查明了糯扎渡坝区复杂岩体的成因，认为坝区岩体经历了复杂的岩浆活动、火山活动和多期构造作用后，产生了一系列原岩蚀变和变形破裂迹象；靠近右岸的丫口后山穹隆的隆起加剧了这些变形破裂从而为风化营力深入到坡体深部提供了良好的通道；两岸岩体介质水力学特性的不同更导致了地下水活动在空间上的不均匀性，从而形成了两岸岩体的差异风化，而风化程度的差异反过来进一步加剧地下水活动的不均匀性。因此，坝区复杂岩体是蚀变—构造—风化共同作用的结果。 采用了四种岩体质量分级评价方案对研究区岩体质量进行了研究，这四种方案包括：工程岩体分级标准(GB50218-94)、水利水电围岩工程地质分类(GB50267—99)、岩体RMR分类(Bieniawski,1973)、岩体质量指数Z分级(小湾,1995)。结果显示，四种分级指标之间具有较好的相关性，岩体质量Z分级和其他的三种方法呈指数关系，RMR和水电围岩工程地质分级方法呈线性关系，而水电围岩工程地质分级与工程岩体分级方法则呈对数关系。其相关系数在0.85以上。在此定量化基础上，结合现场分类以及水利水电工程地质勘察规范，通过对比综合，得到研究区岩体质量分级。 通过建立岩体力学参数与反映岩体质量优劣的指标(如RQD、K_V、V_P、Z、RMR、BQ、T)之间的相关方程，运用不同质量分级的分级定量指标计算相应级别的岩体力学参数值。结果表明，这种方法所求得参数值与实测值吻合很好，在试验资料不充分的部位，可以利用现场测得ROD、V_p等指标，快速求取相应的岩体力学参数值，供设计参考使用。 咸都理工 大学工 学博士 学位论文，2002 采用分形理论，研究了分维值与岩体变形模量和纵波速之间的关系，结果表明：岩体的变形模量并非只受岩体内结构面分布的影响，还受其岩块的变形性质的控制。仅用一个分维数与岩体变形模量的拟合方程来计算所有风化等级岩体的变形参数是不可行的，但是对于同一风化程度的同种岩体（其岩块变形参数相近）分维数和变形模量具有较好的线性相关关系，可以用分维数快速求取该种岩体的变形模量。 运用数值模拟技术，对心墙堆石坝和混凝土重力坝对研究区的工程地质适宜性。研究结果表明：对于混凝土重力坝，按照现在的深开挖方案，坝肩开挖后，土石方开挖量高达820X10‘m‘，且在72dri高程至坡顶将产生大范围的破坏区，采用工程治理将带来巨额的费用。综合比较推荐的两种坝型的适宜性评价结果，表明：心墙堆石坝具有更好的适宜性。更多还原

【Abstract】 Engineering geological feasibility study is a key stage to high-dam construction. Its research findings may have decisive influence on decision-making. Objectives of this research are to evaluate the strength stability and deformation stability of engineering buildings and rock mass within range of influence.In terms of main principles of Dynamic Geo-historical Course Analysis and Systems, field site at Nuozhadu hydropower station, Langcangjiang River, Yunnan Province is investigated in detail.Based on the in situ measured data and numerical modeling results, the research are mainly composed of four parts. Included are: (1) Engineering geological conditions, rock mass mechanical environment and it’s hydraulic parameters at research area. (2) Assessment of rock mass quality and determination of their corresponding mechanical parameters. (3) Study of Geological Engineering Mechanical Model(GEMM). (4) Evaluation of feasibility of planned dam types in course of dam construction and after storage.The main findings of this research are as follows:The researching theory and method system of engineering geological feasibility study of high-dam construction are summarized in this thesis. Furthermore, the study process has been divided into five stages, namely are planning, comparison of dam section, comparison of dam site, comparison of dam axes and special-purpose engineering study. Each stage has its own research objectives and key decisive factor. The whole researching process of engineering geological feasibility is a step by step course from merely considering geological factors to taking the interaction between geological environment and engineering into account.The concept of GEMM (Geology-Engineering-Mechanic Model) has been proposed in this thesis. GEMM is a parameterized model consisted of representative units, boundary units (including natural boundary and artificial boundary), target parameters and key engineering information. It is a kernel and belt in the process of geological feasibility evaluation because it is not only integration of generalized geological conditions and engineering information but also basis of further theoritical analysis and numerical modeling. As an example, A GEMM has been built in combine with the research practice of research area.The formation mechanism of complex rock mass at research area is probed. Research shows that four factors have great influence on the formation of complex rock mass. First, rock mass subjected six times of tectonic movement during long period of geo-history, each tectonic movement produced fractures and associated joints corresponding to the orientation of maximumprincipal stress and deteriorated the properties of fractures formed at former period(s). Second, down-cutting of Langcangjiang River produced unloading fractures. Third, the upheaval of Yakou Vault produced a serial of radial tensile fractures which located xm right-bank side, thus, degraded the rock mass structure of right-bank. Fourth, the intersection and convergence of all these fractures formed a fracture net which served as good channel for all kinds of weathering forces, especially ground water, enter into deep inner part of rock mass. Under the combined action of above-mentioned four factors, the complex rock mass at right bank which consist of two weak rock mass bands and superficial unloading relaxed rock mass came into being.Quality of rock mass has been accomplished by using four kinds of assessment method. Zone maps show that rock mass quality generally has the tendency which decedent with elevation, however, the change of rock mass quality is not gradual but has "skips" at some positions. This manner of change reflected the great influence of texture to rock mass quality.Rock mass mechanical parameters corresponding to individual rock mass quality at different levels are determined by means of correlation analysis and statistical analysis. Results show that calculation outcomes match well with measured mechanical parameters. Thus, mechanical parameter更多还原