论文部分内容阅读
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。
The stability of complex high-steep slopes in Southwest Hydropower Station has always been one of the key technical issues in the construction of hydropower projects. Based on the study of topography, engineering geological characteristics and measured data of the left bank slope of Baihetan Hydropower Station on the Jinsha River, a discrete element model UDEC was used to establish the discrete element model of the left bank bedding slope to excavate the dam foundation slope The stability of the slope excavation process to obtain the stress field, the displacement field, the distribution of plastic zone law, revealing the bedding rock slope deformation instability mechanism. At the same time, combined with the characteristics of microseismic activity in the left bank slope during excavation unloading and stress adjustment, the potential damage area and the slip surface in deep rock mass of the left bank slope are identified and delineated. The comprehensive study shows that the deformation of the left bank slope is mainly affected by the tectonic stress, geological conditions and excavation unloading, among which, the weak structural faces LS_ (3318), LS_ (3319), LS_ (331), LS_ (337) F_ (17) and other dam deformation plays a decisive role in slope excavation. 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.