三维胶凝砂砾石百米级高坝的稳定性分析

为计算130m坝高的三维胶凝砂砾石坝坝基面稳定性,设计了2因素(坝体坡率m、地基弹性模量E)7水平(E为24(微风化岩体)、30、36、42、48、54、60GPa(新鲜岩体))的正交计算方案,采用有限元法进行计算。结果表明,坝体坡率m相同时,随着地基弹性模量E的增大,抗剪断稳定系数K′、抗剪稳定系数K均减小;地基弹性模量E相同时,随着坝体坡率的增大,抗剪断稳定系数K′、抗剪稳定系数K均增大。得到随坝体坡率m、地基弹性模量E变化时坝体稳定系数的变化规律及幅度,并根据《胶结颗粒料筑坝技术导则》、《混凝土重力坝设计规范》,优选出坝体坡率m=0.74、地基弹性模量E=24GPa,为胶凝砂砾石百米级高坝发展、建设起到指导作用。

Stability Analysis of Three-dimensional Cement-Sand-Gravel Hundred Meters Level High Dam

In order to calculate the stability of the foundation surface of the 130 m high three-dimensional cement-sand-gravel dam, two factors (slope ratio m of dam body, elastic modulus E of foundation) and seven levels (E=24 GPa micro-weathered rock mass, 30 GPa, 36 GPa, 42 GPa, 48 GPa, 54 GPa, 60 GPa fresh rock mass) were designed as the orthogonal computing scheme and compared by the finite element method. The results show that the shear resistance stability coefficient K'' and shear stability coefficient K are decreased with the increase of elastic modulus E of foundation when the slope ratio m of dam body is the same; The shear resistance stability coefficient K'' and shear stability coefficient K are increased with the increase of dam slope ratio m when the elastic modulus E of foundation is the same. The variation rules and ranges of stability coefficient with slope ratio m and elastic modulus E of foundation are obtained. And according to "Technical guideline for cemented granular material dams" and " Design specification for concrete gravity dams", the slope ratio of dam body and the elastic modulus of foundation are most preferred choice that m=0.74 and E=24 GPa. Thus, it plays a guiding role in the development and construction of the cement-sand-gravel and hundred meters level high dam.