基于动土压力响应特性的黄土滑坡振动台试验研究  

Shaking Table Experiment of Loess Landslide based on Dynamic Earth Pressure Response Characteristics

作　　者：万金侠[1] 施艳秋 陈小云 WAN Jinxia;SHI Yanqiu;CHEN Xiaoyun(College of Railway Engineering,Jilin Railway Technology College,Jilin 132200,China;China Railway Northwest Research Institute Limited Company,Lanzhou 730000,China;China Building Northwest Design and Research Institute Limited Company,Xi’an 710018,China)

机构地区：[1]吉林铁道职业技术学院铁道工程学院,吉林吉林132200 [2]中铁西北科学研究院有限公司,甘肃兰州730000 [3]中国建筑西北设计研究院有限公司,陕西西安710018

出　　处：《防灾减灾工程学报》2021年第3期586-593,共8页Journal of Disaster Prevention and Mitigation Engineering

基　　金：铁道部科技研究开发计划课题(2011G012-A);吉林省职业技术教育学会年度科研重点课题(2018XHZ012)资助。

摘　　要：为了探讨地震作用下动土压力沿高程和滑面的响应规律,通过大型振动台实验输入X向和Z向地震波,输入幅值逐级增大直到边坡破坏,对沿滑面和沿高程的5个土压力传感器的动土压力峰值分布规律进行分析,并利用基于小波变换的能量提取工具对加载X向和Z向的EL波进行分解,分析其在不同频带的动力响应特性,并进行了加速度峰值分析与动土压力峰值的组合响应分析。研究结果表明:①土压力沿高程和滑面都呈现非线性增加的趋势,加载X向地震波对滑面土体应力影响较为显著,而加载Z向地震波对坡顶面附近土体应力影响较为显著,且加载Z向地震波土压力沿高程放大趋势比加载X向地震波更明显;②输入加速度峰值0.6g时,滑体开始向下滑动,贯通破裂面的产生和动土压力峰值以及加速度峰值同时突变可作为边坡破坏的依据;③使用基于小波变换的能量提取工具对各频段的能量进行提取,发现第一频段的能量占比在95%以上,说明第一频段内土体响应最为剧烈,黄土边坡对地震波运动过程中高频部分具有“滤波作用”,因此进行防护设计时应把这一现象作为设计的考虑因素之一。In order to study the response characteristics of dynamic soil pressure along elevation and the sliding surface under earthquake action,the X-direction and Z-direction seismic waves are input into large-scale shaking table test. The input degree increases gradually until the slope failure.Then analysis the maximum value characteristic about the dynamic soil pressure of five soil pressure sensors along the sliding surface and elevation,and the EL waves loaded in X direction and Z direction are decomposed by using the energy extraction tool based on wavelet transforming.Then analysis the dynamic response characteristics in different frequency bands.Then analysis combination response characteristics about the peak value of acceleration and dynamic soil pressure.The results show that:①The soil pressure increases non-linearly along the elevation and the sliding surface.The stress of soil near the sliding surface is influenced obviously by waves which loading in X direction,then the stress of the soil near the top surface is influenced obviously by waves which loading in Z direction.Furthermore,when loading Z direction waves the amplification trend of soil pressure along elevation is more obvious than loading X direction waves.②When the acceleration peak value is 0.6 g,the soil begins to slide downward.The occurrence of the continuous fracture surface,the sudden change of the dynamic soil pressure peak value and the acceleration peak value at the same time can be regard as the evidence about the failure of slope.③ Extracting the energy of each frequency band is based on the energy extraction tool based on wavelet transforming.To indicate that the energy ratio of the first frequency band is over95%,which show that the soil response is the most intense in the first frequency band,the Loess Slope has the function of filtering the high frequency part of the seismic waves.So this phenomenon should be considered as one of the factors in the protection design.

关 键 词：地震动土压力 振动台 滑面 高程 小波变换 能量提取 

分 类 号：V221.3[航空宇航科学与技术—飞行器设计]