【作者】 叶袁坤；

【导师】 谢全敏；

【作者基本信息】 武汉理工大学 ， 岩土工程， 2010， 硕士

【摘要】 边坡按照性质可以分为岩质边坡和土质边坡,岩堆边坡作为岩质边坡的一种特殊情况,是岩石山坡经过物理、化学作用、形成岩石碎块、碎屑后,通过重力作用或雨水作用搬运至平缓山坡或山坡坡脚的疏松堆积物体。岩质边坡的动力问题求解主要分为拟静力法和数值模拟法,拟静力法的研究成果比较丰富,理论体系较成熟,但是有明显的缺点。而基于有限差分方法的FLAC程序,在岩土学界应用比较广泛。但是动力方面的边坡永久位移的研究相对较少,是目前该领域研究的热点和难点,特别是近两年地震频发,这就要求我们对动荷载作用下的岩质边坡的永久位移问题进行深入的研究。本文总结了边坡动力问题的研究现状,对有限差分原理进行了介绍,详细地总结和分析了动力求解方法,运用有限差分程序FLAC软件对岩堆边坡的永久位移的影响因素进行详细的分析,包括频率、持时、振幅、坡高和坡角五个方面。主要开展了以下工作：(1)在总结前人研究成果的基础上,将地震作用下边坡稳定性的影响因素归纳为边坡所处的地质背景、边坡的岩体结构类型和地层岩性组合、边坡的地形地貌条件以及边坡的水文地质条件等方面；(2)对边坡有限差分理论进行了详细的叙述,并对有限差分动力方程求解方法进行总结和分析,讨论了动力方程及计算方法、非线性动力方程和计算方法、M-C模型本构关系和屈服准则；(3)探讨了粘弹性边界条件的设置对计算结果的影响,主要得出了以下五个方面的结论：①动力输入时间对边坡的永久位移的影响,随着持续时间的增加,边坡的永久位移成增大的趋势；②边坡永久位移随着频率的增加反而呈现降低的趋势,低频地震波导致的边坡的永久位移值明显高于高频地震波,频率为10HZ是一个分界点,高于10HZ时,随着频率的增加,边坡的永久位移有明显的下降趋势,而10HZ-20HZ之间,边坡的永久位移没有太大的变化。说明边坡对动荷载的高频部分由过滤的作用；③振幅对位移的影响,随着振幅的增加,边坡的永久位移呈现明显的上升趋势,变化幅度很大；④边坡在受到地震荷载的作用下,其永久位移随着坡高的增大并不是单调的增加,本文中选取坡高H=15m,30m,45m,60m,75m,100m,120m,140m,150m,当坡高在15m-75m变化时边坡的永久位移呈现明显的增大趋势；当坡高在75m～100m变化时,边坡的永久位移基本上保持不变；当坡高在100m～150m变化时,边坡的永久位移呈现下降的趋势。这说明,边坡的坡高对边坡的永久位移的影响不是单调的,而是存在一个临界的坡高,大概是100m左右,当坡高小于临界坡高时,边坡的永久位移随着坡高的增加呈现增大趋势,当坡高超过临界坡高时,边坡的永久位移随着坡高的增加反而呈现下降的趋势；⑤边坡的坡角对边坡永久位移的影响,随着坡角的增加,边坡的永久位移呈现增大的趋势,当坡角超过60。时,坡角的改变对边坡的永久位移影响不是很大。(4)结合工程实际,对宜巴高速三里花岩堆边坡的永久位移进行了数值模拟计算,分析结果表明：在地震动荷载的作用下,1-1断面和2-2断面的最大永久位移分别为27.83cm和23.61m,出现在边坡的坡脚位置,这对工程实际具有指导意义。更多还原

【Abstract】 According to property,slope can be devided into rock slope and soil slope. As a kind of rock slopes,slope of accumulation of rock mass has special geological conditions.It is formed by rock crumb which produced by physical and chemical action. The ways to analyze dynamic stability problem of rock slope can be classified as pseudo-static methods and numerical simulation methods. Although the achievements of Pseudo-static methods are abundant and theoretical systems matured, it still has many obvious defects.Based on the finite difference method,FLAC program is used widely in rock and soil engineering world.But little scholar make research on permanent displacement of slope committed by dynamic load.Especially in the past two years,earthquakes occured frequently.After all,it id necessary for us to make research on permanent displacement of slope commetted by dynamic load.This article summarizes the problem of slope dynamic situation.Based on the finite difference principle, a detailed summary and analysis of the dynamic solution method, the finite difference program FLAC software on the rock pile slope of the permanent displacement of a detailed analysis of the factors, including the frequency, duration, amplitude, and slope angle high five. Mainly to carry out the following work:(1)On the basis of previous achievements,the influence factor of slope stability under dynamic loads is classified as geological background,combination of the structure of slope an rock mass properties,conditions of terrain and landform and hydrogeology condition.(2)The paper describes the finite difference method detailly.The method to solve dynamic equation is summaried and analyzed.Dynamic equation and computing methods,nonlinear dynamic equation and calculation methods, Mohr-Colunm elastoplastic constitutive relations ang yield critertion are also discussed.(3)The influence patten of viscoelasticity boundary under equation of rock slope is discussed.The main following works has been done in this paper,①the influence of slope pernament displacement made by dynamic duration is dicussed, with increasing duration,the slope permanent displaceent increased.②the influence of slope permanent displacement made by frequency is debated in the paper,with increasing frequency,the slope permanent displacement is reduced all the while,③the influence of slope permanent displacement made by amplitude of vibration,④the influence of slope permanent displacement made by slope altitude,⑤the influence of slope permanent displacement made by slope angle.(4)Based on SanLiHua slope of acummulation of rock mass of YiBa highway projects,the paper has done nemerical simulated computation used flac2d program. And finally the dynamic response of SanLiHua acummulation of rock mass under seimic loade named kobe are analyzed,and some useful conlusions derived.更多还原