平推式滑坡承压水模型研究

Study on the artesian water model of translational landslide

传统的平推式滑坡渗流模型无法计算透水层中的渗透流量和潜水渗出高度,而常假设两者并不随后缘裂隙水头而改变,这影响到承压水范围求解的准确性。为此构建新的承压水模型,基于地下河槽一维渗透理论,给出透水层中承压水作用范围、渗透流量和潜水渗出高度的计算方法;基于新昌县下山滑坡水文地质资料,采用极限平衡法计算边坡稳定安全系数,并对比分析新、旧模型计算结果的差异;最后分析相关参数的内在关系,讨论地质参数、尺寸参数以及初始水力条件参数对透水层流量、承压水范围及渗出面高度的影响。结果表明:(1)后缘裂隙水头对承压水作用范围、渗透流量和潜水渗出高度的影响较大,不能忽视这一影响;(2)新模型下的平推式滑坡稳定安全系数更为合理可靠;(3)地质参数、尺寸参数和初始条件参数中任意参数改变,承压水作用范围、透水层渗透流量及渗出面高度均可能受到影响。

Seepage discharge and exit water level in permeable layer cannot be computed with traditional seepage model in translational landslides,and both are assumed invariable as the water level in the slope cracks changes,which influences the accuracy of computation results in the range of artesian water.A new seepage model of translational landslide was thus established.Based on one-dimensional seepage theory of underground river channel,a new method was proposed to compute the action range of artesian water,seepage discharge and water level in seepage exit.Based on the geological data of Xiashan landslide,the safety factor was computed with different models and the outputs were discussed.Finally,the intrinsic relations and sensibility analysis of relative parameters including geological parameters,dimensional parameters and initial parameters of hydraulic condition were studied.Results showed that the range of artesian water,the seepage discharge and the water level in seepage exit were influenced significantly by the water level in the cracks of slope.The safety factor of slopes based on the new model is more reasonable and accurate.Any change in the model′s parameters made a difference in the range of artesian water,unit discharge and water level in seepage exit.