【作者】 曹彦彦；

【导师】 王来贵；

【作者基本信息】 辽宁工程技术大学 ， 工程力学， 2009， 硕士

【摘要】 地震是地壳快速释放能量过程中造成振动,期间会产生地震波的一种自然现象,是对人类危害最严重的地质灾害。斜坡包括天然斜坡和人工斜坡,是地球表面具有露天侧向临空面的地质体,是自然界中最为常见的地表特征之一,而岩体及其弱层为低抗拉介质,承受拉应力区域的岩体易发生拉张破坏。地震引发的破坏性比较大的边坡崩塌、滚石加上滑坡等也非常严重,滑坡还造成堰塞湖及相关危害,所以研究地震动力作用下岩体边坡破坏过程和规律,在工程实践中具有非常重要的意义。有限元方法是目前应用最为广泛的研究工具,但是传统的有限元方法,是建立在连续性假设基础上的,不能模拟岩石拉张破裂后形成的不连续结构,不能直接处理岩石拉破坏现象问题。本文基于岩体拉张破坏理论,应用可模拟拉张破裂的有限元软件对不同强度地震作用下的斜边坡拉张区域及瞬时拉张破裂现象进行数值模拟。就不同弱层数量、不同坡面倾角斜坡模拟试件,加载不同方向、不同强度地震波,共进行了20次数值模拟。分别从同一模型不同强度地震波加载;相同地震波同一坡角不同弱层加载;同一地震波不同坡角不同弱层加载三个方面进行对比。结果表明,拉应力区在地震过程中,不断变化,同一角度边坡弱层越深受拉区域越大,并且地震的加速度值越大,拉应力水平就越高,受拉范围就越大。地震引起的拉张破坏中起主要作用的是x方向地震波,y方向地震波对坡面拉张破坏的影响较小。地震作用下岩体产生了附加应力且随地震进程不断调整;原岩应力与附加应力叠加而形成的总应力场随着地震的进行发生相应改变。斜边坡在一定范围内可能产生拉应力。拉应力区域在地震过程中不断变化,并且地震加速度值越大,拉应力水平就越高,最终产生初始的拉张裂纹;随着受拉范围的增大,裂纹由坡体向坡面延伸,导致边坡岩体拉张破坏。更多还原

【Abstract】 Crustal earthquakes are caused by quick release of energy during the vibration, will produce seismic waves during a natural phenomenon, the most serious harm to human geological disasters. Slopes, including the natural slopes and artificial slopes, is invading the earth’s surface with the open side surface geological body, is the nature of the surface features of the most common one, while the lower layer of rock and its weak tensile media, to bear tensile stress area prone to tensile damage of rock. The devastating earthquake relatively large slope failure, coupled with the Rolling Stones were also very serious landslides, landslides also caused landslide-dammed lakes and associated hazards, the study of rock slope under seismic dynamic failure process and patterns of practice in engineering has a very important significance.The finite element method is currently the most widely used research tools, but the traditional finite element method, is built based on the assumption of continuity can not be simulated rocks formed after the tensile rupture of non-continuous structure, and can not directly deal with the problem of rock failure phenomena of Latin America . Based on rock tensile failure theory, the application can simulate tensile rupture of the finite element software for different intensity earthquakes on steep slope under the action of tensile tensile rupture of the regional and temporal phenomenon of numerical simulation. The number of different weak layers with different slope angle slope simulated specimen, loading different directions and intensity of seismic waves, conducted a total of 20 times the value of simulation. Respectively from the same model of earthquakes of various magnitudes Microwave and load; the same as the same slope angle seismic waves in different weak layers loading; the same slope angle seismic waves in different layers of different load three aspects of a weak comparison. The results show that tensile stress zones in the earthquake process, constantly changing, the same angle of slope of the weak layer of the more popular drawing area larger, and the larger the value of the earthquake acceleration, the higher the level of tensile stress, the greater the tension range. Tensile damage caused by the earthquake played a major role in the x direction of seismic wave, y the direction of seismic waves on the slope tensile damage was less affected. Seismic rock produced under additional stress and adjustment process will continue with the earthquake; situ rock stress and additional stress superimposed stress field formed by the total conduct of earthquake occurrence with the corresponding changes. Inclined slope that may arise within a certain tensile stress. Tensile stress region in the process of changing the earthquake and the earthquake acceleration values of the larger the higher the level of tensile stress and eventually produce the initial tensile crack; as the tension increases the scope of the crack extends from the slope to the slope , resulting in tensile damage of rock slope.更多还原