摘要
为了给汽车振动作用下结构性黄土劣化损伤及边坡致灾机理研究提供理论支撑,研究汽车振动作用下黄土阶状坡动力响应规律,以安子路(安塞至子长)某黄土公路阶状坡为研究对象,采用野外调查和现场监测的方法,总结了黄土阶状坡的变形破坏模式及特点,获取了不同车辆类型、速度和位置下边坡的汽车振动信号。在对监测信号进行统计分析的基础上,得到了边坡的振动响应规律和频谱特性,主要结论如下:(1)边坡的振动响应随汽车荷载的增加而增强;随着汽车荷载的增加,振动响应强烈区域由二级坡逐渐迁移到一级坡;(2)汽车荷载较小时,振动波放大效应明显,汽车荷载较大时,振动波放大效应减弱,且Z方向波表现为振动衰减;(3)X方向波的频谱分布为单峰状,主频集中在17~65 Hz;Z方向波的频谱分布为多峰状,主频集中在22~185 Hz;(4)振动波在坡体中传播时的频率变化与车辆的类型、速度和位置的相关性较小,主要是由坡体自身决定;(5)汽车振动作用会造成黄土阶状坡应力状态发生改变,在黄土阶状坡设计中,边坡坡度不宜太大,一级和二级坡不宜太高,同时应重点对一级坡和二级坡进行坡面防护。该问题的研究,对揭示黄土阶状坡的动力响应及该类型边坡的防护具有一定的理论和实际意义。
In order to provide theoretical support for the study of structural loess degradation damage and slope disaster mechanism under the automobile vibration,to research the dynamic response rule of loess stepped slope under the action of automobile vibration,taking a loess stepped slope located in Ansai-Zizhang highway as the research object,the failure modes and characteristics of loess stepped slope are summarized,the vehicle vibration signals of different types,speeds and positions on the loess stepped slope are obtained by field investigation and monitoring. Based on the statistical analysis of the monitoring signals,the vibration response rule and the spectrum characteristics of the slope are obtained. It is concluded as follows:(1) The vibration response of the slope increases with the increase of e vehicle load. As the vehicle load increases,the area with strong vibration response gradually migrates from the second grade slope to the first grade slope.(2) The amplification effect of the vibration wave is obviously when the vehicle load is small,while the amplification effect of the vibration wave is weakened when the vehicle load is large,and the Z-direction wave appears as the vibration attenuation.(3) The X-direction wave’s frequency distribution is single-peak,and the main frequency is concentrated in 17-65 Hz. Z-direction wave’s frequency distribution is multi-peaked,and the main frequency is concentrated in 22-185 Hz.(4) The frequency variation of the vibration wave propagating in the slope is less relevant to the type,speed,and position of the vehicle. It is mainly determined by the slope itself.(5) The stress state of the loess stepped slope will change under the action of vehicle vibration. In the design of loess stepped slope,the gradient of the slope should not be too large,and the first and second grade slopes should not be too high. Meanwhile,the slope protection should be focused on the first and second grade slopes. This research result is benefit for revealing the dynamic response of loess stepped slope,which has certain theoretical and practical significance for protection of this type of slope.
作者
李鹏
刘世杰
郭敏
徐继维
LI Peng;LIU Shi-jie;GUO Min;XU Ji-wei(School of Geological Engineering and Geomatics,Chang'an University,Xi'an Shaanxi 710054,China;Open Research Laboratory of Geotechnical Engineering,Ministry of Natural Resources,Xi'an Shaanxi 710054 ,China;Key Laboratory for Geo-hazards in Loess Area,Ministry of Natural Resources,Xi'an Shaanxi 710054,China)
出处
《公路交通科技》
CAS
CSCD
北大核心
2019年第7期53-62,共10页
Journal of Highway and Transportation Research and Development
基金
国土资源部黄土地质灾害重点实验室开放基金资助项目(KLGLAMLR201506)
中央高校基本科研业务费资助项目(310826151048,310826173305,310826171011)
关键词
道路工程
动力响应
振动监测
黄土阶状坡
汽车振动
road engineering
dynamic response
vibration monitoring
loess stepped slope
vehicle vibration
