地震作用下双面坡破坏模式及动力响应试验研究

发布时间：2018-03-11 15:43

本文选题：地震作用　切入点：双面坡　出处：《西南交通大学》2017年硕士论文　论文类型：学位论文

【摘要】：我国位于世界两大地震带之间,地震频仍,而西部山区恰恰与地震带相重合,地震引起的山体滑坡对该地区的生命财产安全造成重大威胁,往往是地震次生灾害中危害性最大的一种。因此,研究掌握边坡在地震作用下的破坏规律具有重大的现实意义。本文依托西南交通大学振动台系统,在前人研究的基础上,针对边坡的变形破坏过程、破坏模式、破坏机理及其动力响应规律进行了初步的研究,设计并完成了五组不同条件边坡的大型振动台试验,主要探讨了地震动参数及土体岩土力学性质对边坡动力稳定性的影响。通过对试验影像资料及传感器采集的大量数据进行分析,主要得出了以下几点结论:(1)土体含水率及压实度对边坡的破坏模式影响显著,对边坡动力响应规律具有一定程度影响。(2)五组边坡的破坏模式分别为浅表溃滑型、拉剪-溃滑型、溃散型、蠕滑型以及溃崩型。边坡表面的位移变化曲线可以从一定程度上反映边坡破坏模式的部分信息,有助于揭示边坡的破坏规律。(3)本试验条件下,坡面及坡内测点加速度放大系数呈现出明显的高程放大效应,但沿水平方向测点加速度放大系数并未表现出趋表放大的特点。边坡加速度放大效应与输入波幅值之间的关系受边坡含水率影响。随输入波频率增加(趋于边坡自振频率),边坡各测点加速度放大系数呈现出增大的趋势。边坡对低频正弦波的动力响应不明显。(4)本文的结果很好地验证了地震作用下双面坡的初动拉剪加速破裂效应、重复拉剪效应以及双坡共剪效应,对进一步揭示地震作用下双面坡的破坏机理具有一定意义。
[Abstract]:China is located between the two major earthquake zones in the world. Earthquakes are frequent, and the western mountainous area coincides with the seismic belt. The landslides caused by earthquakes pose a major threat to the safety of life and property in this area. Therefore, it is of great practical significance to study and master the failure law of slope under earthquake. This paper relies on the shaking table system of Southwest Jiaotong University, based on the previous research. According to the deformation and failure process, failure mode, failure mechanism and dynamic response of slope, five groups of large-scale shaking table tests of slope with different conditions are designed and completed. This paper mainly discusses the influence of ground motion parameters and the mechanical properties of soil and soil on the dynamic stability of slope. Through the analysis of the experimental image data and a large number of data collected by the sensor, the dynamic stability of the slope is analyzed. The main conclusions are as follows: (1) soil moisture content and compaction have a significant effect on the failure mode of the slope, and have a certain degree of influence on the dynamic response of the slope. The failure modes of the five groups of slopes are shallow-surface collapsing and shear-collapsing, respectively. The displacement curve of slope surface can reflect some information of slope failure mode to some extent, which is helpful to reveal the failure rule of slope. The acceleration magnification factor of the slope surface and the test point inside the slope shows obvious elevation amplification effect. However, the acceleration magnification factor of the measured point along the horizontal direction does not show the characteristic of tendency amplification. The relation between the acceleration amplification effect of slope and the amplitude of input wave is affected by the water content of the slope, and the frequency of the input wave increases (tends to the slope). The dynamic response of slope to low frequency sine wave is not obvious. The repeated tension-shear effect and the double-slope co-shear effect have certain significance for further revealing the failure mechanism of the double-sided slope under earthquake action.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU435

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