土体结构性对突发性边坡失稳的控制作用

Analysis of the sudden slope instability controlled by the soil structure

云南、广西等地部分边坡在变形与破坏过程中常表现出一定的突发性。经分析,土体的高结构性强度有可能是导致该类现象产生的原因之一,但尚未得到验证。传统的边坡稳定分析方法诸如有限元强度折减法、极限平衡法均着重于边坡安全系数的求解,强调稳定到不稳定状态的突变,对不同土质边坡在滑坡过程中坡体变形程度的强弱很难加以分析。针对以上问题,通过离散元软件PFC2D模拟土体的结构性,分析结构性土质边坡的失稳变形规律。结果表明:边坡潜在滑面上土体结构性的损伤是导致结构性土坡失稳的主要原因之一。土体的初始结构性强度越高,边坡失稳的突发性越强,灾前位移变形越小。

Some slopes in Yunnan,Guangxi and other places often show some suddenness during deformation and destruction.After analysis,the high structural strength of the soil may be one of the reasons for this phenomenon,but it has not yet been verified.Traditional slope stability analysis methods such as finite element strength reduction method and limit equilibrium method all focus on solving the slope safety factor,emphasizing the sudden change to the unstable state,and the degree of slope deformation of different soil slopes during the landslide process.It is difficult to analyze strengths and weaknesses.To solve the above problems,the structural properties of the soil are simulated by the discrete element software PFC 2D to analyze the instability deformation law of the structural soil slope.The results show that the structural damage of the potential slippery surface of the slope is one of the main reasons leading to structural instability.The higher the initial structural strength of the soil,the stronger the sudden instability of the slope,and the smaller the displacement deformation before the disaster.