基于可靠性理论的边坡稳定性评价研究

【作者】 马显春；

【导师】 赵法锁；

【作者基本信息】 长安大学 ， 地质工程， 2006， 硕士

【摘要】 随着我国大规模工程建设的开展，越来越多的项目涉及到边坡问题，而边坡工程的安全稳定与否不可避免的要遇到许多不确定性因素，如岩土体性质参数的复杂性、多变性、随机性等一系列因素，这些不确定性因素使常规的定值分析方法在应用中有颇多不足，因此，可靠性理论被引入到边坡稳定性分析中。可靠性理论从概率的角度对影响边坡稳定的各种因素的不确定性进行定量分析，从而定量得到坡体稳定的不确定性，是常规方法很好的补充和发展。 边坡的变形破坏是一个长期的变化过程，其稳定性受边坡内部因素和外部因素等多种条件的影响，包括边坡岩土体类型及性质、边坡地质结构、边坡形态、地下水、振动作用、气候条件、风化作用、植被条件及人类工程活动等，特别是人类工程活动及地下水对边坡稳定影响较大。本文对各影响因素的作用机理进行了系统的归纳和总结。 为了研究各主要影响因素对边坡稳定性的影响程度，本文以王良寺滑坡为例，采用正交试验法对其进行了敏感性分析，考虑的因素主要有粘聚力(c)、内摩擦角(φ)、重度(γ)、地下水位(h_w)和坡高(h)。研究结果表明，在各因素中影响程度由大到小依次为φ、c、h_w、γ、h。 在边坡稳定可靠性分析中，采用了组合参数法搜索概率意义上的最危险滑动面。概率危险滑面以最小可靠度指标为依据，它比按变量均值搜索到的危险滑面更接近实际，且可以利用现有的定值分析法程序。稳定系数法是建立在确定性概念上的一种传统边坡稳定性评价方法，并不能真正反映边坡设计的可靠性，本研究以王良寺滑坡为例，从可靠性上对边坡稳定性进行评价，得出近似概率危险滑面的可靠性指标为0.47，均值危险滑面的可靠性指标为0.54。更多还原

【Abstract】 With the development of extensive engineering constructions in our country, more and more engineering projects must deal with slope problems; these can inevitably fall across a lot of uncertain factors, such as complexity, levity and randomicity of characters and parameters of rock and soil mass. These uncertainties have already been making general certain analysis means having rather shortage. So it is necessary to introduce the reliability theory in the research on the stability analysis of slope systems. Reliability theory can make quantificational analysis of uncertain factors which influence the stability of slope systems in the probability point of view. This method can educe quantificational result of uncertain factors of slope stability. It is a very useful method and is complementarity and development to traditional methods.The deformation and collapse of slope is a long-time changing course, the slope stability is affected by the slope’s inherent factors and external factors, including the types and natures of rocks and soils, the slope geological structures, the slope shapes, the groundwater, the vibration, the climatic conditions, the weathering, the slope’s vegetation and mankind’s project activities, and so on. Of which, mankind’s project activities and the groundwater are of great importance. In this paper, the action mechanisms of influence factors are summed up and summarized.In order to study the influence degree on the slope stability by the major factors, taking Wang Liang Si temple as an example, make an sensitive analysis of it by the cross experiment method, taking the following factors into consideration: cohesion(c), angle of internal friction ((?)), gravity(γ), the ground water lever (h_w) and the height slope (h). The result is that, the influences from big to small listing as: (?),c,h_w,γ,h.In the probability reliability analysis of slope stability, search for the most critical slip surface in probability by combination parameter method. With the basis of the smallest reliability index, the probability critical slip surface is farm more near to practice than the critical slip surface searched for by the average of the variables, and its resolving may resort to the existing deterministic analysis method procedure. The safety coefficient method is a更多还原