黄土斜坡地震稳定性分析及区划

发布时间：2018-01-04 06:35

本文关键词：黄土斜坡地震稳定性分析及区划　出处：《中国地震局兰州地震研究所》2013年硕士论文　论文类型：学位论文

【摘要】：黄土高原沟壑纵横、地形地貌条件复杂，地质构造复杂、断裂发育、新构造活动强烈、强震频发，与黄土有关的地震灾害与地质灾害十分发育。据统计，黄土高原强震多发区Ⅵ度以上的地震烈度区达33.51万km2。在黄土高原这一高烈度的地震活动背景下，黄土由于其架空孔隙结构和弱胶结特性及其因由而生的动力易损性，在强烈振动作用下其微观结构和物理力学性质会发生适应性变化，进而影响其宏观的强度和变形特性，，甚至导致失稳破坏。鉴于我国黄土高原地区新构造运动活跃和强震多发背景，加之黄土本身所具有的较强的动力易损特性，本文主要研究强震作用下黄土斜坡的动力响应特征、变形特征以及滑坡稳定性的区划方法。针对上述科学问题，本文开展的主要工作和得到结论如下：（1）采用对研究区域现场勘察、测试与室内动三轴试验相结合的方法，确定模型岩土体的力学参数。（2）利用FLAC3D对一般三维斜坡模型进行静力数值计算，研究土体覆盖厚度和坡度对坡体稳定性的影响，得到了安全系数随坡度和覆盖厚度变化的影响曲线。（3）在天水人工地震波作用下，计算三维斜坡理想模型的稳定性，并进行地震反应特征研究。结果表明，在动力作用下，坡体产生相对位移，滑动趋势明显；模型计算存在边界效应。（4）对天水地区4处典型斜坡进行三维建模，研究了模型在天水人工波作用下的稳定性并总结了地震动放大效应特征。（5）采用因子分析法结合GIS的空间分析方法对研究区域进行斜坡稳定性区划，得到了2%、10%和63.5%三种超越概率下的斜坡稳定性区划图，通过该图件显示的滑坡潜在滑动危险与实际灾害详情对比，发现区划结果与实际灾情吻合度高。
[Abstract]:in that background of the high intensity seismic activity in the loess plateau , the micro - structure and the physical and mechanical properties of the loess due to its overhead pore structure and weak cementation characteristic can be changed adaptively , which can affect the macroscopic strength and deformation characteristics of the loess plateau and even lead to instability damage . In view of the active and strong earthquakes background of the new tectonic movement in the Loess Plateau of China , the dynamic response characteristics , deformation characteristics and zoning methods of loess slope under strong earthquakes are studied in this paper . The main work and conclusion are as follows : ( 1 ) The mechanical parameters of the model rock and rock mass are determined by the method of combining site investigation , test and indoor dynamic triaxial test in the study area . ( 2 ) Using FLAC3D to calculate the static force of the general three - dimensional slope model , the influence of soil covering thickness and slope on the stability of the slope body is studied , and the influence curve of the safety coefficient with the slope and the thickness of the cover is obtained . ( 3 ) Under the action of artificial seismic waves , the stability of the ideal model of three - dimensional slope is calculated , and the seismic response characteristics are studied . ( 4 ) Three - dimensional modeling of typical slope in Tianshui area is carried out , and the stability of the model under the action of Tianshui artificial wave is studied and the characteristic of ground motion amplification effect is summarized . ( 5 ) Using a factor analysis method and GIS spatial analysis method , the slope stability zoning was carried out in the study area , and the slope stability zoning map of 2 % , 10 % and 63 . 5 % was obtained .

【学位授予单位】：中国地震局兰州地震研究所
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU435

【共引文献】