【作者】 郑金明；

【导师】 刘高；

【作者基本信息】 兰州大学 ， 地质工程， 2013， 硕士

【摘要】 在我国大型水利水电工程中,水电资源丰富的区域大多数位于西部深切河谷地区。受岸坡陡峭,河谷狭窄地形条件的制约,往往需要将发电机群设置在地下洞室中,高边墙、大跨度的地下厂房必然会遇到复杂的地质条件和难以预料的工程地质问题,工程围岩稳定性成为工程设计与施工中的关注重点。本文以拉西瓦水电站主厂房及主变室地下厂房洞室为例,主要从工程地质环境条件研究、室内试验与现场原位测试、数值分析等理论方法及手段,研究坝区岩体结构及强度特征,并依据河谷演化过程,重现地应力场形成机制及分布特征。在进行详细的现场勘察和试验基础上,从基本地质条件、断裂发育特征、应力场特征、岩体质量和洞室稳定性等多方面进行地下主厂房及主变室洞室围岩稳定性分析研究。对于拉西瓦水电站地下厂房洞室工程地质研究,主要内容包括：(1)研究区域地质环境及坝址区工程地质条件；(2)研究厂房区结构面的产状、发育程度、表面形态等发育特征和分布规律,绘制倾向节点等密图；(3)采用Q分类、RMR分类、水电规范分类分级标准评价围岩质量,以及厂房区岩体质量空间展布特征；(4)研究应力场特征,包括区域地应力分布特征及规律、坝区应力空间分布特征、模拟河谷形成演化过程等；(5)运用有限单元、有限差分软件,建立数值计算模型,计算分析工程开挖后引起的地应力场重分布特征,评价地下洞室围岩稳定性,为支护设计提供理论依据。更多还原

【Abstract】 The rich hydropower resources area in our country are mostly located in the the western deep valley region. Restricted by steep riverbank and narrow valley terrain conditions, the hydroelectric generator group was usually set in the underground cavern, the underground powerhouse with high sidewall and large span will inevitably encounter complex geological conditions and unpredictable engineering geological problems, among which the stability of surrounding rock is the biggest concern.In this paper, underground powerhouse cavern of the the Laxiwa Hydropower main plant and the main transformer room is taken for the example, the rock mass structure and strength characteristics are studied mainly from the engineering geological environment conditions, indoor test, in-situ testing, numerical analyses, theoretical methods and means, and the field stress formation mechanism and distribution characteristics are reproduced based on valley evolution process. On the basis of detailed site survey and testing, form basic geological conditions, fracture development characteristics, characteristics of the stress field, rock mass and cavern stability, the stability of surrounding rock for the cavern of underground main powerhouse and the main transformer room are studied.For Laxiwa hydropower station underground powerhouse cavern engineering geological studies, the main research topics include:(1) the regional geological environment and engineering geological conditions of the dam area;(2) the development characteristics and distribution law for occurrence of structural surface, degree of development, surface morphology of the plant area, drawing tendency node density figure;(3) using Q classification, RMR classification, hydropower specification standards to evaluate surrounding rock quality and rock mass quality space distribution characteristics of plant area;(4)characteristics of the stress field, including the regional stress distribution characteristics and laws, engineering area stress spatial distribution characteristics, and analog valley formation and evolution; (5) using the finite element and finite difference software to establish numerical calculation model, analyses of excavation caused secondary stress field distribution characteristics, and evaluation of the stability of underground caverns to provide a theoretical basis for support design.更多还原