摘要
为探究地震对含软弱夹层矿山边坡稳定性的影响,通过FLAC3D软件分析了地震作用下含软弱夹层边坡的水平和竖直加速度动力响应特性,以及软弱夹层的存在及其厚度对边坡动力响应特性的影响,并利用拟静力法分析地震加速度对边坡稳定性的影响,最后采用动态强度折减法并结合拟静力分析、地震动力响应特性分析含软弱夹层边坡在地震作用下的失稳模式与破坏机理。研究结果表明:(1)在坡体中上部,水平和竖直加速度迅速增大,表现出高程放大效应,在同一高程水平上,坡面加速度大于坡内,表现出趋表效应。(2)薄软弱夹层对边坡整体的动力响应起到促进作用,厚软弱夹层则是起抑制作用;薄软弱夹层边坡加速度最大值出现在坡肩处,厚软弱夹层边坡加速度最大值出现在软弱夹层与坡面的交界处。(3)边坡安全系数随水平、竖向地震惯性力的增大而减小。(4)含软弱夹层边坡在地震作用的失稳模式为“沿软弱夹层发生层间平面滑动—拉裂破坏”;软弱夹层使地震波发生反射和折射,是影响边坡动力响应特性的主要原因,也是边坡失稳的内在原因。
In order To explore the influence on slope stability with weak intercalated,analyzed by FLAC3D and the earthquake with weak interlayer slope under the action of horizontal and vertical acceleration dynamic response characteristics,and the existence of the weak interlayer and the influence of thickness on the slope dynamic response characteristics,the quasi-static method is used to analyze the influence of seismic acceleration on slope stability.Finally,dynamic strength reduction method combined with pseudo-static analysis and seismic dynamic response characteristics is used to analyze the instability mode and failure mechanism of slope with weak interlayer under earthquake action.The results show that:(1)In the middle and upper part of the slope,the horizontal and vertical accelerations increase rapidly,showing the elevation amplification effect.At the same elevation level,the slope acceleration is larger than the slope acceleration,showing the surface effect.(2)Thin weak interlayer promotes the dynamic response of the slope,while thick weak interlayer inhibits the dynamic response.The maximum acceleration of the thin weak interlayer slope appears at the shoulder of the slope,and the maximum acceleration of the thick weak interlayer slope appears at the junction of the weak interlayer and the slope.(3)The safety factor of slope decreases with the increase of horizontal and vertical seismic inertia force.(4)The instability mode of the slope with weak interlayer under earthquake action is"interlayer plane slip-tensile fracture failure along the weak interlayer".The weak interlayer causes the seismic wave to reflect and refract,which is the main reason that affects the dynamic response characteristics of slope and the internal reason of slope instability.
作者
盛建龙
严寒冰
胡斌
王庭元
钟卓希
SHENG Jianlong;YAN Hanbing;HU Bin;WANG Tingyuan;ZHONG Zhuoxi(School of Resources and Environmental Engineering,Wuhan University of Science and Technology,Wuhan 430081,China;Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources,Wuhan 430081,China)
出处
《金属矿山》
CAS
北大核心
2022年第12期214-220,共7页
Metal Mine
基金
国家自然科学基金项目(编号:U1802243,41672317)
湖北省技术创新专项重大项目(编号:2017ACA184)
武科大重大科技项目培育类创新团队(A类)(编号:2018TDX01)。
关键词
软弱夹层
动力响应
加速度放大系数
变形破坏机制
gently-inclined soft interlayers
dynamic response
acceleration amplification coefficient
deformation failure mechanism
