岩质边坡的自震频率对其加速度放大系数的影响  

Influence of natural frequency of rock slope on its acceleration amplification factor

作　　者：李朝阳 向波 蒋瑜阳 LI Chaoyang;XIANG Bo;JIANG Yuyang(Sichuan Highway Planning,Survey,Design and Research Institute Ltd.,Chengdu,Sichuan 610041,China)

机构地区：[1]四川省公路规划勘察设计研究院有限公司,成都610041

出　　处：《湖南城市学院学报（自然科学版）》2023年第4期1-5,共5页Journal of Hunan City University:Natural Science

基　　金：交通运输部建设科技项目(2009318221097);四川交通科技项目(2016B2-2)。

摘　　要：以不同坡高、坡角和岩性的岩质边坡作为研究对象,首先,采用ANSYS的模态分析功能研究了岩质边坡的自振频率随不同影响因素的变化规律;其次,将数值计算模型导入CDEM软件中计算岩质边坡在不同频率正弦波作用下的动力放大系数;最后,以此探讨了岩质边坡自振频率对其动力放大系数的影响.结果表明:1)硬岩和软岩边坡的自振频率均随着坡高的增加而减小,且坡角对于前3阶边坡自振频率影响较小.2)当边坡自振频率大于地震波频率时,加速度放大系数随着地震波频率的增加而增大;当边坡自振频率小于地震波频率时,加速度放大系数随着地震波频率的增加而减小.3)坡高和坡角相同时,加速度放大效应主要受岩性影响,且软岩边坡的加速度放大系数整体上大于硬岩边坡.Taking the rock slope with different slope height,slope angle and lithology as the research object,the variation law of the natural frequency of the rock slope with different influencing factors was firstly studied by using the modal analysis function of ANSYS.Secondly,the numerical calculation model was imported into CDEM software to calculate the amplification coefficient of the rock slope under the sine waves with different frequencies.Finally,the influence of the natural frequency of rock slope on its amplification coefficient was discussed.The results show that:1)the natural frequencies of hard rock and soft rock slopes decrease with the increase of slope height,and the slope angle has little effect on the natural frequency of the first three slopes.2)When the natural vibration frequency of the slope is greater than the seismic wave frequency,the acceleration amplification coefficient increases with the increase of seismic wave frequency,and decreases with the increase of the seismic wave frequency when the slope natural vibration frequency is less than the seismic wave frequency.3)When the slope height and slope angle are the same,the acceleration amplification effect is mainly affected by lithology,and the acceleration amplification coefficient of soft rock slope is larger than that of hard rock slope as a whole.

关 键 词：岩质边坡 数值模拟 自振频率 加速度放大系数 

分 类 号：U416.14[交通运输工程—道路与铁道工程] P315.9[天文地球—地震学]