白鹤滩河谷演化模拟及P_2β_3玄武岩级别评估  

Study of evolutional simulation of Baihetan river valley and evaluation of engineering quality of jointed basalt P_2β_3

作　　者：荣冠[1,2] 王思敬[1] 王恩志[1] 刘顺桂[3] 

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084 [2]武汉大学水利水电学院,武汉430072 [3]中国科学院地质与地球物理研究所,北京100029

出　　处：《岩土力学》2009年第10期3013-3019,共7页Rock and Soil Mechanics

基　　金：国家自然科学基金资助研究(No.50879063;No.50639100);中国博士后科学基金资助研究(No.20060400434)

摘　　要：详细分析了白鹤滩坝址河谷边坡柱状节理玄武岩岩体地质条件和特征,建立了合适河谷边坡演化离散元的计算模型,考虑坝址关键地层P2β3可能的岩体质量范围进行了多种工况河谷演化模拟计算。在此基础上深入研究了各工况河谷现今阶段边坡应力分布、变形情况、屈服区及稳定系数等基本规律,并与目前河谷实际的地质条件及现状进行了全面对比。最后采用拟似度信息量评分法对P2β3岩层工程级别进行了初步评定,认为白鹤滩水电站可行性研究阶段坝址P2β3岩层按III1类质量岩体来评估其工程性状和确定相应岩体力学参数较适合。同时,坝址河谷边坡岩体的工程特性可参考相应工况的模拟结果评价。The geological conditions and characteristics of rock masses of columnar jointed basalt in valley slope of dam site in Baihetan hydropower station are introduced in detail; the proper distinct element model of Baihetan river valley is established; and the river valley evolvement is simulated under several engineering cases taking into account the possible rock masses qualities of the key stratum of P2β3. Based on the simulation results, we have thoroughly investigated the basic law of stress distribution, deformation situation, yield zone and stability factor of Baihetan river slope nowadays under all cases; and the comprehensive contrast studies are carried out between simulation results and the actual geological status of river valley nowadays. Finally, the methodology of gradation by the information of similar degree is introduced to evaluate the rock masses level of key stratum P2β3; and we conclude that the global quality of Baihetan jointed basalt P2β3 can be marked as the level of III1 to evaluate its engineering properties and to determine relevant mechanical parameters at the phase of feasibility investigation; simultaneously the engineering properties of rock masses in valley slope of dam site can be evaluated according to the relevant simulation results.

关 键 词：白鹤滩水电站 河谷演化 离散元法 柱状节理玄武岩 岩体工程级别 

分 类 号：TU452[建筑科学—岩土工程] P642[建筑科学—土工工程]