土坡地震稳定性影响因素的敏感性分析

发布时间：2018-05-26 06:43

本文选题：地震 + 边坡稳定　；参考：《中国地震局工程力学研究所》2015年硕士论文

【摘要】：我国是地震和地质灾害严重的国家,边坡失稳是常见的地质灾害。强烈的地震作用往往会诱发大量的边坡失稳从而导致严重的地质灾害。地震诱发的滑坡崩塌数量多、规模大、突发性强,往往具有极强的毁灭性,是我国地震灾害严重的主要原因。在工程抗震设防等工作中需要对地震作用下边坡的稳定程度进行估计,分析影响边坡稳定性的关键因素并对其敏感性进行分析十分重要。本文对地震作用下边坡稳定影响因素的敏感性问题进行研究,主要成果如下。(1)回顾了边坡影响因素敏感性分析的研究进展,明确了影响因素敏感性分析的工程目的和意义,提出了本文所采用的敏感性分析方法,包括单因素敏感性系数分析法,单因素敏感性斜率分析法与多因素正交试验分析法。(2)论述了拟静力强度折减法的基本原理,并结合所采用的数值模拟软件FLAC,讨论了基于FLAC软件求解边坡稳定性系数的求解流程。(3)在给定地震加速度水平的条件下,利用FLAC边坡数值模拟软件,对边坡稳定影响因素进行了单因素敏感性分析。分析结果表明,在地震加速度水平分别为0.03g、0.05g、0.1g、0.15g、0.2g与0.3g的条件下,各影响因素的敏感性大小依次为坡高坡角粘聚力岩土重度内摩擦角。在地震加速度水平分别为0.4g与0.8g的条件下,各影响因素的敏感性大小依次为坡高粘聚力坡角岩土重度内摩擦角。(4)在给定地震加速度水平的条件下,利用FLAC边坡数值模拟软件,对边坡稳定影响因素进行了多因素敏感性分析。分析结果表明,在地震加速度水平分别为0.05g与0.1g的条件下,各影响因素的敏感性大小依次为坡高坡角粘聚力内摩擦角岩土重度。在地震加速度水平分别为0.15g与0.2g的条件下,各影响因素的敏感性大小依次为坡高坡角粘聚力岩土重度内摩擦角。在地震加速度水平分别为0.3g与0.4g的条件下,各影响因素的敏感性大小依次为坡高粘聚力坡角岩土重度内摩擦角。(5)对比了单因素与多因素敏感性分析结果,分析了两种方法所得结论有所差异的原因。并基于两种方法所得到的结论,提出了边坡稳定性综合评价的初步参考方案。
[Abstract]:Slope instability is a common geological hazard in China, where earthquake and geological disasters are serious. Strong earthquakes often induce a large number of slope instability, leading to serious geological disasters. Earthquake induced landslide collapse is a major cause of earthquake disaster in China. It is necessary to estimate the stability of slope under seismic action in engineering seismic fortification and so on. It is very important to analyze the key factors affecting slope stability and analyze its sensitivity. In this paper, the sensitivity of influencing factors of slope stability under earthquake is studied. The main results are as follows: (1) the research progress of sensitivity analysis of slope influencing factors is reviewed, and the engineering purpose and significance of sensitivity analysis of influencing factors are defined. The sensitivity analysis methods used in this paper, including single factor sensitivity coefficient analysis, single factor sensitivity slope analysis and multi-factor orthogonal test analysis, are presented. The basic principle of quasi-static strength reduction method is discussed. In combination with the numerical simulation software FLACadopted, the flow chart of solving slope stability coefficient based on FLAC software is discussed. Under the condition of given seismic acceleration level, the FLAC slope numerical simulation software is used. The single factor sensitivity analysis of the influencing factors of slope stability is carried out. The results show that when the seismic acceleration level is 0.03g ~ 0.05g ~ (0.1) g ~ (-1) 0.15g ~ 0.2g and 0.3g respectively, the sensitivity of each influencing factor is the angle of heavy internal friction of cohesive rock and soil in order of slope high slope angle. Under the condition that the seismic acceleration is 0.4g and 0.8g, the sensitivity of each influencing factor is in order of slope high cohesion, slope angle, rock and soil serious internal friction angle. Under the condition of given earthquake acceleration level, the FLAC slope numerical simulation software is used. The influence factors of slope stability are analyzed by multi-factor sensitivity analysis. The results show that the sensitivity of the influencing factors is in turn the degree of internal friction angle rock and soil under the earthquake acceleration level of 0.05 g and 0.1 g respectively. When the seismic acceleration level is 0.15g and 0.2g respectively, the sensitivity of each influencing factor is in turn the angle of heavy internal friction of cohesive rock and soil at the high slope angle. Under the condition of earthquake acceleration of 0.3 g and 0.4 g, the sensitivity of each factor is in order of slope high cohesion, slope angle, serious internal friction angle, etc.) the results of single factor and multi factor sensitivity analysis are compared. The reasons for the difference between the two methods are analyzed. Based on the conclusions obtained by the two methods, a preliminary reference scheme for comprehensive evaluation of slope stability is proposed.
【学位授予单位】：中国地震局工程力学研究所
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU435

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