不确定信息处理方法在边坡稳定性分析中的应用

发布时间：2018-07-17 20:01

【摘要】：边坡的稳定性分析问题一直都是岩土工程安全中十分重要的研究内容。到目前为止，边坡稳定性分析方法主要分为两类：一类是基于安全系数并有着大量工程应用实例的极限平衡法；另一类是利用计算机强大的计算能力来模拟大型边坡内部单元力学分析的数值分析法。但是这些方法还存在许多不足之处：极限平衡法对于现实中客观存在的岩土参数的随机不确定性没法考虑在内，导致由于忽略这些不确定性，含有相同安全系数的边坡却有着差距很大的边坡失稳概率；数值分析法由于采用了几何非线性迭代，导致时常存在收敛性问题，并且对于边坡失稳的判断依据也存在许多争议。针对这些传统方法存在的一些问题如因参数或者模型的不确定性导致的结果不精确，本文从不确定信息处理方法中寻找出一些可以有效处理这类问题的方法。本文的主要成果如下：（1）首先回顾了各种经典的边坡稳定方法以及几种常用不确定信息处理，，并从中提炼出比较可靠的边坡分析的模型框架与对应的符合处理边坡的不确定理论处理工具，为进一步的研究应用打下基础。（2）针对传统的瑞典圆弧法取多个滑坡面安全系数最小值存在的不足，在利用随机集对岩土参数不确定性表示的基础上，通过Dempster组合规则融合多个滑坡面的安全系数，得到一个综合的更加精确的结果。（3）由于传统方法无法对强降雨下的边坡稳定性进行定量分析，本文基于不确定理论建立边坡稳定性与降雨时长的随机函数关系，并利用可传递信度模型将结果转化为概率分布，得出一个新的的分析结果。（4）针对黄河小浪底水库典型边坡工程进行实地取样，建立室内室外研究模型，应用不确定信息方法对其进行分析，并用实验验证了该方法在实际边坡工程中应用的有效性。
[Abstract]:Slope stability analysis is always an important research content in geotechnical engineering safety. Up to now, slope stability analysis methods are mainly divided into two categories: one is the limit equilibrium method based on safety factor and has a large number of engineering applications; The other is the numerical analysis method to simulate the internal mechanical analysis of large slope by using the powerful computing power of computer. However, these methods still have many shortcomings: the limit equilibrium method can not take into account the random uncertainty of the objective geotechnical parameters in reality, which leads to the neglect of these uncertainties. The slope with the same safety factor has a wide slope instability probability, and the numerical analysis method often has convergence problem because of the geometric nonlinear iteration, and there are many controversies on the judging basis of slope instability. In view of the inaccuracy of some problems existing in these traditional methods, such as the uncertainty of parameters or models, this paper looks for some effective methods to deal with these problems from the uncertain information processing methods. The main achievements of this paper are as follows: (1) at first, various classical slope stability methods and several common uncertain information processing are reviewed. The model framework of slope analysis and the corresponding uncertain theoretical tools for slope treatment are extracted from the model. It lays a foundation for further research and application. (2) in view of the shortcomings of the traditional Swedish circular arc method in taking the minimum value of safety factor of multiple landslide surfaces, the uncertainty of geotechnical parameters is expressed on the basis of random sets. By combining the safety factors of multiple landslide surfaces with the Dempster combination rule, a more accurate result is obtained. (3) the traditional method can not quantitatively analyze the slope stability under heavy rainfall. In this paper, the stochastic function relationship between slope stability and rainfall duration is established based on uncertainty theory, and the result is transformed into probability distribution by using transferable reliability model. A new analysis result is obtained. (4) the typical slope engineering of Xiaolangdi Reservoir of the Yellow River is sampled on the spot, the indoor and outdoor research model is established, and the uncertain information method is used to analyze it. The effectiveness of this method in practical slope engineering is verified by experiments.
【学位授予单位】：杭州电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU43

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