基于离散元模拟和微震监测的白鹤滩水电站左岸岩质边坡稳定性分析

发布时间：2018-03-09 15:03

本文选题：岩质边坡　切入点：数值模拟　出处：《岩土力学》2017年08期 　论文类型：期刊论文

【摘要】：西南地区水电站复杂高陡边坡的开挖稳定性一直是水电工程建设的关键技术问题之一。在研究金沙江白鹤滩水电站左岸边坡地形地貌、工程地质特性、地应力实测资料等基础上,利用通用离散元程序UDEC建立左岸顺层边坡离散元模型,进行开挖卸荷过程坝基边坡的稳定性分析,获得边坡开挖过程应力场、位移场、塑性区分布规律,揭示了顺层岩质边坡变形失稳机制。同时,结合左岸边坡开挖卸荷和应力调整过程微震活动特征,识别和圈定了左岸边坡深部岩体潜在损伤区域和滑裂面。综合研究结果表明,左岸边坡变形主要受构造应力、地质条件和开挖卸荷等综合因素影响,其中软弱结构面LS_(3318)、LS_(3319)、LS_(331)、LS_(337)、F_(17)等对坝基边坡开挖变形起决定性作用。研究成果可为左岸边坡开挖和支护施工提供参考,同时也为类似顺层岩质边坡工程开挖支护提供研究思路。
[Abstract]:The excavation stability of complex high and steep slopes of hydropower stations in southwest China is always one of the key technical problems in hydropower engineering construction. In this paper, the topographic and geomorphological features and engineering geological characteristics of the left bank slope of Baihetan Hydropower Station in Jinsha River are studied. On the basis of the measured data of in-situ stress, the discrete element model of the bedding slope on the left bank is established by using the general discrete element program UDEC. The stability analysis of the dam foundation slope during excavation and unloading is carried out, and the stress field and displacement field of the slope during excavation are obtained. The distribution of plastic zone reveals the mechanism of deformation and instability of bedding rock slope, and combines with the characteristics of microseismic activity during excavation unloading and stress adjustment of the left bank slope. The potential damage area and slip surface of deep rock mass on left bank slope are identified and delineated. The comprehensive results show that the deformation of left bank slope is mainly affected by comprehensive factors such as tectonic stress, geological conditions and excavation unloading, etc. Among them, LSn3318 / LS-1 / L _ S _ T _ 331 / L _ S _ S _ T _ 331 / L _ S _ 1 / L _ S _ 1 / L _ S _ 1 / L _ S _ T _ 17) play a decisive role in the excavation and deformation of the dam foundation slope. The research results can provide a reference for the excavation and support construction of the left bank slope, and also provide a research idea for the excavation and support of the similar bedding rock slope engineering.
【作者单位】：四川大学水利水电学院水力学与山区河流开发保护国家重点实验室;中国长江三峡集团公司;
【基金】：国家自然科学基金面上项目(No.51679158) 国家重点基础研究发展计划(973计划)(No.2015CB057903)~~
【分类号】：TV223

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