滑坡地震稳定性评价方法研究

发布时间：2018-05-19 11:36

  本文选题：滑坡 + 地震稳定性　； 参考：《云南大学》2015年硕士论文

【摘要】：滑坡灾害破坏性大、治理难度高,特别是地震作用下的稳定性问题十分复杂,涉及到多门学科,目前仍是土木工程界的一大难题。 本文以小湾滑坡、花坪滑坡和八浪沟滑坡为研究对象,运用传递系数法和Janbu法计算了滑坡的稳定系数。研究两种方法计算结果的差异,发现：两算法计算结果的变化量小于0.05且变化率I小于4.5%,因此传递系数法与Janbu法计算的滑坡稳定系数都是合理的,Janbu法的计算结果相对偏于保守。 运用Janbu法分析了滑体土容重、滑带土粘聚力和内摩擦角三个工程参数对滑坡稳定性的影响：滑体土的容重与稳定系数呈负相关,滑带土的粘聚力、内摩擦角与稳定系数呈正相关,其中滑坡稳定系数对滑带土内摩擦角的变化最为敏感。进而分析了地震发生时,各工程参数对滑坡稳定性影响的变化：地震作用下,各工程参数对滑坡稳定性影响的总体趋势不变,但影响程度均有小幅度降低。 运用有限元法,输入三种实际地震波,计算分析了三个滑坡在小震、中震、大震作用下的稳定性,其中地震响应计算方法为等效线性化法,稳定性计算方法为有限元应力法,得到了滑坡在地震作用下的稳定系数时程曲线。分析计算结果发现：滑坡稳定系数最小的时刻并不是地震波加速度最大的时刻；地震波的选取对地震稳定性分析结果的影响极大：在不同地震作用下,原本稳定的滑坡均存在不同程度的失稳现象。 最后,对比分析了几种滑坡地震稳定性计算方法的优劣,并针对防治工程等级为Ⅰ级、Ⅱ级、Ⅲ级的三类滑坡提出了地震稳定性评价建议。 通过对滑坡地震稳定性评价方法的研究,不仅揭示滑坡在地震作用下的稳定性变化规律,探讨了滑坡地震稳定性的评价方法和影响因素,还提出了工程上评价滑坡地震稳定性的建议。
[Abstract]:Landslide disaster is very destructive and difficult to manage, especially the stability problem under earthquake is very complex, which involves many disciplines, and is still a difficult problem in civil engineering field at present. In this paper, the stability coefficient of Xiaowan landslide, Huaping landslide and Balanggou landslide are calculated by transfer coefficient method and Janbu method. By studying the difference between the two methods, it is found that the variation of the results of the two methods is less than 0.05 and the rate of change I is less than 4.5. Therefore, the calculation results of the landslide stability coefficient calculated by the transfer coefficient method and the Janbu method are both reasonable and the results of the two methods are relatively conservative. Janbu method is used to analyze the influence of three engineering parameters on landslide stability: bulk density of sliding soil, cohesive force of sliding zone soil and angle of internal friction: the bulk density of sliding soil is negatively related to the stability coefficient, and the cohesive force of sliding zone soil is negative. The internal friction angle is positively correlated with the stability coefficient, and the landslide stability coefficient is the most sensitive to the variation of the internal friction angle of the sliding zone soil. Furthermore, the influence of engineering parameters on landslide stability is analyzed. Under earthquake, the general trend of the influence of engineering parameters on landslide stability is not changed, but the influence degree is reduced by a small margin. Using the finite element method, three kinds of actual seismic waves are inputted, and the stability of the three landslides under the action of small earthquake, moderate earthquake and large earthquake is calculated and analyzed. The seismic response calculation method is equivalent linearization method, and the stability calculation method is finite element stress method. The time history curve of landslide stability coefficient under earthquake action is obtained. The results of analysis and calculation show that the time when the landslide stability coefficient is the smallest is not the moment when the seismic wave acceleration is the largest, and the selection of seismic wave has a great influence on the seismic stability analysis result: under the different earthquake action, The original stable landslide has different degrees of instability phenomenon. Finally, the advantages and disadvantages of several landslide seismic stability calculation methods are compared and analyzed, and some suggestions for seismic stability evaluation are put forward for three types of landslide with grade 鈪，

本文编号：1909948