【摘要】：巖質邊坡的穩(wěn)定性主要受控于結構面,當巖坡中的結構面信息不明確時,可以采用臨界傾角對應的最危險滑面來分析巖坡的平面滑動穩(wěn)定性。同時由于實際邊坡的各項指標均具有一定的變異性,在邊坡分析時應當考慮這些變異性對邊坡穩(wěn)定性的影響,所以基于參數不確定性的邊坡可靠性分析方法更為合理。本文即從臨界傾角的解析求解展開,利用拉丁超立方抽樣(LHS)可靠性分析方法,分析了同時考慮參數不確定性和最危險滑面不確定性的巖質邊坡可靠性,優(yōu)化了可靠性分析方法的計算精度和效率,并將研究成果應用到工程實踐。本文的主要工作及主要結論如下：(1)通過解析計算給出了三種邊坡模型下的臨界傾角顯式求解公式,有助于巖坡穩(wěn)定性和可靠性研究以及邊坡工程設計等多個方面的分析和應用。(2)基于一次二階矩法和蒙特卡羅法在可靠性分析中所存在的問題,本文采用以分層抽樣為核心算法的LHS方法來計算巖坡的可靠性,并通過具體算例對三種方法的計算結果做了比較,結果表明LHS方法在對輸入變量分布函數的擬合以及收斂速度等方面都具有一定的優(yōu)勢,不僅有效地提高了邊坡可靠性分析的效率,而且能保證計算的精度。(3)考慮參數不確定性和最危險滑面的不確定性,本文對香港秀茂坪巖質邊坡進行了可靠性分析,計算結果顯示基于體系可靠度方法計算的邊坡失效概率最大,概率臨界滑面得到的結果次之,最危險滑面得到的失效概率最小,可見后面兩種方法都有低估邊坡系統(tǒng)失效概率的可能,所以通過比較說明在巖坡的可靠性分析當中,更應該采用體系可靠度的方法對邊坡進行評價。(4)在上述巖坡體系可靠度計算的基礎上,分析了參數變異性對臨界傾角和安全系數的影響,結果表明抗剪強度參數的敏感度最大。還分析了參數間相關性對計算結果的影響,指出隨著參數間負相關性的增加,邊坡體系的失效概率隨之降低。(5)將臨界傾角的求解公式和體系可靠度分析方法應用到山東臨沂換流站站址邊坡的評價當中,同時采用安全系數和失效概率兩個指標來評價邊坡,結果表明該邊坡安全可靠。
[Abstract]:The stability of rock slope is mainly controlled by the structural plane. When the information of the structural plane in the rock slope is not clear, the most dangerous slip surface corresponding to the critical slope angle can be used to analyze the plane sliding stability of the rock slope. At the same time, the influence of these variability on slope stability should be considered in slope analysis, so the reliability analysis method based on parameter uncertainty is more reasonable. Based on the analytical solution of critical dip angle and the (LHS) reliability analysis method of Latin hypercube sampling, the reliability of rock slope considering both parameter uncertainty and most dangerous slip surface uncertainty is analyzed in this paper. The calculation accuracy and efficiency of reliability analysis method are optimized, and the research results are applied to engineering practice. The main work and conclusions of this paper are as follows: (1) the explicit solution formulas of critical slope angle under three kinds of slope models are given by analytical calculation. It is helpful for the study of rock slope stability and reliability, and the analysis and application of slope engineering design. (2) based on the problems of first-order second-moment method and Monte Carlo method in reliability analysis, In this paper, the LHS method with stratified sampling as the core algorithm is used to calculate the reliability of rock slope, and the results of the three methods are compared through concrete examples. The results show that the LHS method has some advantages in fitting the distribution function of input variables and the convergence rate, which not only improves the efficiency of slope reliability analysis, but also improves the efficiency of slope reliability analysis. And the accuracy of calculation can be guaranteed. (3) considering the uncertainty of parameters and the most dangerous slip surface, the reliability analysis of Xiumaoping rock slope in Hong Kong is carried out. The results show that the slope failure probability is the largest based on the system reliability method, followed by the probability critical slip surface, and the most dangerous slip surface has the lowest failure probability. It can be seen that the latter two methods have the possibility of underestimating the failure probability of the slope system, so it is shown by comparison that in the reliability analysis of the rock slope, The method of system reliability should be used to evaluate the slope. (4) on the basis of the reliability calculation of the rock slope system mentioned above, the influence of parameter variability on critical inclination angle and safety factor is analyzed. The results show that the sensitivity of shear strength parameters is the highest. The influence of the correlation between parameters on the calculation results is also analyzed, and it is pointed out that with the increase of the negative correlation between parameters, The failure probability of slope system decreases with it. (5) the formula of critical dip angle and system reliability analysis method are applied to evaluate the slope of Linyi converter station in Shandong province. At the same time, the safety factor and failure probability are used to evaluate the slope, and the results show that the slope is safe and reliable.
【學位授予單位】：南京大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：P642.22

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相關期刊論文 前1條

1 姚耀武，，陳東偉;土坡穩(wěn)定可靠度分析[J];巖土工程學報;1994年02期

本文編號：2334750