左岸边坡强卸荷块体系统的稳定问题是白鹤滩水电站题重要工程技术问题之一。针对左岸边坡地形地质条件、变形特征及变形机理的研究,表明结构面组合的三维块体滑动失稳为其主要的破坏模式。常规刚体极限平衡法和连续介质力学方法在求解复杂块体系统稳定时均存在一定的局限性。以块体单元自动识别方法为前处理程序,建立白鹤滩左岸边坡块体系统三维模型,基于弹黏塑性块体单元法(BEM)计算特定块体强度储备安全系数,进行边坡稳定性研究,分析边坡控制性结构面及其关键块体,研究结果与常规刚体极限平衡分析和地质力学模型试验基本一致。块体单元法的分析成果为左岸边坡加固处理提供了依据,同时对复杂块体系统岩体边坡的稳定性研究具有一定指导意义。
Abstract
The stability of unloading block on the left bank slope has been a critical issue for Baihetan hydropower station. Study on the geologic condition, failure characteristics and deformation mechanism indicates that the sliding failure of three dimensional rock blocks along discontinuities is the main potential failure mode of the left slope. General limit equilibrium method and continuum mechanics method both have some limitations in analyzing the stability of complex block system. In this paper, the method of automatically identifying block is employed to establish the block system model of the left slope. Three-dimensional elasto-viscoplastic block element method(BEM) is adopted to calculate the strength reserve safety factor of sliding blocks. And the controlling discontinuities and the key blocks are revealed. Research results are consistent with both the general limit equilibrium analysis and geomechanical model test, which supports the reinforcement measures for the left slope. The study in this paper could be a guide for the stability analysis of complicated rock block system.
关键词
岩石边坡 /
块体系统 /
块单元法 /
稳定安全系数 /
白鹤滩水电站
Key words
rock slope /
block system /
block element method /
safety factor /
Baihetan Hydropower station
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 陈祖煜,弥宏亮,汪小刚.边坡稳定三维分析的极限平衡法.岩土工程学报,2001,23(5):525-529. (CHEN Zu-yu,MI Hong-liang,WANG Xiao-gang. A Three-dimensional Limit Equilibrium Method for Slope Stability Analysis. Chinese Journal of Geotechnical Engineering,2001, 23(5): 525-529.(in Chinese))
[2] BENKO B. Numerical Modeling of Complex Slope Deformations.Saskatoon, Canada: Department of Geological Sciences, University of Saskatachewan, 1997:366-372.
[3] EBERHARDT E, STEAD D, COGGAN J, et al. An Integrated Numerical Analysis Approach to the Randa Rock Slide//Proceedings of the 1st European Conference on Landslides. Prague, Czech Republic, June 24-26, 2002:355-362.
[] DAWSON E M, ROTH W H, DRESCHER A. Slope Stability Analysis by Strength Reduction. Geotechnique, 1999, 49(6): 835-840.
[4] PRIEST S D, SAMANIEGO J A. A Model for the Analysis of Discontinuity Characteristics in Two Dimensions//Proceedings of the 5th ISRM Congress. Melbourne, April 10-15, 1983:199-207.
[5] 吴建宏,大四有三,石根华,等.三维非连续变形分析理论及其在岩石边坡数值仿真中的应用.岩石力学与工程学报,2003,22(6):937-942. (WU Jian-hong, OHNISHI Y, SHI Gen-hua. Three-dimensional Discontinuous Deformation Analysis and Its Application to the Rock Slope Toppling. Chinese Journal of Geotechnical Engineering,2003, 22(6): 937-942.(in Chinese))
[6] KAWAI T. A New Discrete Model for Analysis of Solid Mechanics Problem. Science Kenkyn,1977,29(4):208-210.
[7] CHEN S H. A New Development in Elastic-visco-plastic Block Theory of Rock Masses//Proceedings of the Eighth International Conference on Computer Methods and Advances in Geomechanics, West Virginia (USA) A. A. Balkema, May 22-28, 1994: 2235-2240.
[8] 陈胜宏. 岩体的广义弹粘塑性块体理论. 水利学报,1996, (1): 78-84. (CHEN Sheng-hong. A General Formulation of Elasticvisco-plastic Block Theory of Rock Masses. Journal of Hydraulic Engineering, 1996, (1):78-84. (in Chinese))
[9] 郑惠峰,汪卫明,陈胜宏. 弹粘塑性块体单元法在龙滩水电站右坝肩边坡稳定分析中的应用. 岩土力学,2006,27(1):107-112. (ZHENG Hui-feng, WANG Wei-ming, CHEN Sheng-hong. Application of Elasto-viscoplastic Block Element Method to Stability Analysis of Right Abutment Slope in Longtan Hydropower Project. Rock and Soil Mechanics, 2006, 27(1): 107-112.(in Chinese))
[10] 石根华. 数值流行方法与非连续变形分析. 裴觉民,译,北京:清华大学出版社,1997. (SHI Gen-hua. Numerical Manifold Method and Discontinuous Deformation Analysis. Translated by PEI Jue-min. Beijing:Tsinghua University Press,1997. (in Chinese))
[11] 汪卫明, 陈胜宏. 三维岩石块体系统的自动识别方法. 武汉水利电力大学学报, 1998, 31(5): 51-55. (WANG Wei-ming, CHEN Sheng-hong.Automatic Identification Method for Three dimensional Rock Block Systems. Journal of Wuhan University of Hydraulic and Electric Engineering, 1998, 31(5): 51-55. (in Chinese))
PDF(1689 KB)
