土质边坡地震动力响应规律研究

Dynamic Response Analysis of Soil Slope under Seismic Wave

地震往往会触发大量的山体滑坡,给人类和社会带来巨大灾难。为研究探索土质边坡在地震作用下的动力响应规律,本文建立了二维均质边坡有限元模型,模拟计算了其在地震作用下的动力响应,对地震响应中学术界和工程界最为关心的加速度、位移和频谱特性响应进行了研究分析,并得到以下几点结论:①在坡顶和坡面处,与输入地震动加速度时程比较,输出加速度峰值出现的时刻有滞后现象;②坡体内部对输入地震动PGA存在垂直和临空面放大作用,同时垂直放大作用呈现出节律性变化的特点;③地震作用下坡体的最大变形在水平方向上出现在坡脚处,在竖直方向上出现在坡肩处;④边坡体内部对输入地震动的频谱成份产生滤波作用,滤掉了输入地震动中的高频成份,且随着高度的增加,这种滤波作用呈现增强的趋势。

Earthquakes often trigger a large number of landslides, which bring huge disaster to human and society. To explore the dynamic response rules of soil slope under seismic wave, we establish a two-dimensional finite element model of homogeneous slope, and simulates the dynamic response of the slope under seismic. Then we analyze the slope seismic response of the acceleration, displacement and spectrum characteristic which are mostly concerned about by the academic and engineering fields. Our conclusions of the study include： （1） In comparison with the input earthquake waves, the time of output acceleration peak in the top and surface of the slope presents hysteresis phenomenon. （2） The PGA amplification effect of the input seismic waves is existed in the slope＇s free face, also along the vertical, which presents a rhythmic vertical amplification change. （3） After the seismic action, the maximum horizontal displacement of the slope are located in slope foot, and the maximum vertical displacement of the slope appeared at slope shoulder. （4） The slope has filtering effects on the high frequency spectrum component of the input earthquake waves. With the increase of height, such effect has the trend of aggrandizement.