层状反倾边坡变形特征及影响因素分析

Analysis on influential factors and deformation characteristics of toppling slope

借助金沙江某水电站左岸边坡岩体参数,利用离散元软件UDEC/3DEC对层状反倾边坡的主控影响因素（边坡高度、边坡坡度、层面倾角、层面力学参数、坡面与层面夹角等）进行多工况数值模拟分析,揭示了不同影响因素下层状反倾边坡倾倒变形的条件及破坏特征。计算结果表明各影响因素均对边坡倾倒变形有显著影响,边坡层面力学参数的影响尤为显著;边坡在坡角β40°,层面倾角γ＆gt;50°时,随着各影响因素的不同组合与变化,边坡倾倒变形趋势显著增加,边坡的破坏模式主要表现为延性弯曲倾倒和脆性折断倾倒破坏;坡面与层面夹角的变化对边坡倾倒变形及边坡潜在破坏模式均有显著影响,当坡面与层面夹角Ψ在0°~90°时,随Ψ值的增大边坡潜在破坏模式由典型的弯折倾倒破坏模式向圆弧形滑动破坏模式转变。

Based on the rock mass parameter of left bank slope of Jinsha river hydropower station, the influence of slope height, slope angle, dip angles of layer, mechanical parameters of layer and angle between layer and slope on stability and collapse of toppling slope were analyzed with orthogonal analysis using UDEC. The results show that each of the above factors have influence on the stability and collapse of toppling slope, the influence of mechanical parameters of layer is particularly significant; It is found when the slope angle less than 40~ and dip angles of layer less than 50~, the failure trend of the slope collapse is not obvious,when the slope angle more than 40~ and dip angles of layer more than 50~, the failure trend of the slope collapse increased significantly, slope failure mode is disjunction; the angle between layer and slope also has great influence on the stability and collapse of toppling slope,the slope failure mode transition from disjunction to arc-shaped sliding failure with increasing of the angle between layer and slope when angle with levels at 0°-90°.