论文部分内容阅读
运用离散元数值模拟技术,对北川新中崩滑体在具地域性和空间非均质性的地震纵横波时差耦合作用下产生崩滑破坏的动力全过程进行了研究,确定了该斜坡体在强震动力作用下产生崩滑破坏的形成机制及主控因素。研究表明:①对于新中崩滑体的先期崩滑破坏而言,由于其距离初始震中较远,故源自初始震源的地震纵横波到达该斜坡体的时差较长,为约15.21 s,而该斜坡体在地震纵波作用于斜坡体后8 s后即开始破裂,故其先期崩滑破坏是受到地震纵波产生的水平与竖向拉裂耦合作用所致,并以水平拉裂作用占优,而后期的抛射及运动过程则是受到地震纵横波的耦合作用所致;②对其发生先期崩滑的主控因素言,在地震构造组合机制、岩体结构与构造、斜坡岩体风化程度及物理力学参数等因素既定的情况下,地震纵波产生的水平与竖向拉裂耦合作用是诱发斜坡体产生初期崩滑破坏的主控因素,而斜坡所处地形(如高程差、沟谷延伸方向)则是促使破坏后的斜坡体形成后续碰撞解体及碎屑流等运动过程的控制诱发因素;③该斜坡体动力响应特征值的放大效应表明,其放大系数值从大到小依次是水平加速度>竖向加速度>水平速度>竖向速度,该结果与斜坡体发生先期崩滑破坏的形成机制及主控因素相符合,即地震纵波产生的水平加速度起到了优势破坏作用。以上研究为强震动力作用下的斜坡体先期崩滑破坏提供了新方法。
The discrete element numerical simulation technique is used to study the dynamic process of the collapse and collapse of the Xinzhong collapse landslide in Beichuan, under the coupled seismic wave and shear wave propagation with regional and spatial heterogeneity. The results show that Mechanism and Main Control Factors of Collapse and Destruction Caused by Strong Motions. The results show that: (1) For the previous collapse and collapse of the Xinzhong collapse landslide, the time lag between the longitudinal and longitudinal waves originating from the initial source reaching the slope body is relatively long, about 15.21 s because of the distance from the initial epicenter, The ramp body began to rupture 8 seconds after the seismic longitudinal wave was applied to the ramp body. Therefore, the collapse and collapse of the ramp body was caused by the coupled coupling of horizontal and vertical tensile waves produced by the longitudinal compressional wave and dominated by the horizontal pull- While the post-projectile and motion processes are caused by the coupling of seismic waves. (2) The main controlling factors of the collapse and slippage in the early stage are the combination mechanism of seismotectonics, the structure and structure of rock mass, the weathering degree of slope rock mass, Physical and mechanical parameters and other factors given established circumstances, the coupling of vertical and horizontal seismic waves generated by longitudinal cracking and sloughing induced by the main collapse and collapse of the main controlling factor, while the slope where the topography (such as elevation, valley extension) It is the control inducing factor that causes the destructed slope body to form the follow-up collision disintegration and debris flow; ③ The magnifying effect of the characteristic value of the dynamic response of the slope body shows that the magnification value of the slope body dynamic response value increases from large to large Followed horizontal acceleration> vertical acceleration> horizontal velocity> vertical speed, and the main factors of the formation mechanism of destruction of the pre-Slump result consistent with the occurrence of the ramp member, i.e. horizontal seismic waves generated longitudinal acceleration plays a role in destruction advantages. The above research provides a new method for the early collapse and collapse of slopes under strong earthquake.