Failure Mechanisms of Toppling Rock Slopes Using a Three-Dimensional Discontinuous Deformation Analysis Method
Failure Mechanisms of Toppling Rock Slopes Using a Three-Dimensional Discontinuous Deformation Analysis Method
复制标题
利用三维不连续变形分析方法研究崩塌岩质边坡的破坏机制
DOI：
10.1007/s00603-019-01797-6
复制
发表时间：
2019-10-01
影响因子：
6.2
通讯作者：
Kang, Fei
中科院分区：
文献类型：
--
作者：
Liu, Guoyang;Li, Junjie;Kang, Fei
倾倒是不连续面控制岩质边坡的一种典型破坏模式。非连续变形分析（DDA）作为一种离散数值方法，非常适合模拟节理岩体中形成的岩块系统的运动过程、接触变形以及大位移和变形。采用三维DDA方法，引入整体接触理论，研究了岩质边坡的倾倒破坏机理。考虑动力平衡条件，对倾倒边坡进行了分析，推导了相应的计算公式。阐述了整体接触理论的代数计算和力学计算，并将其应用到三维DDA方法中。研制了一套研究块体倾倒过程的实验装置，对不同块体分布和不同条件下的块体倾倒过程进行了一系列室内实验。通过与分析方法和室内实验结果的对比，验证了三维DDA方法的准确性。通过算例分析，包括一个典型的倾倒边坡、一个理想的山体边坡和一个真实的倾倒边坡，进一步研究了倾倒边坡的破坏机理。结果表明，三维DDA方法可以有效地预测边坡失稳，模拟倾倒边坡的破坏过程。基于动力学的计算公式、试验和三维DDA分析的结果丰富了边坡倾倒失稳的条件。同时，提出了倾倒破坏的一般现象和规律。
Toppling is a representative failure mode of discontinuity-controlled rock slopes. As a discrete numerical method, discontinuous deformation analysis (DDA) is well-suited for simulating the movement process, contact transformation, and large displacement and deformation of rock block systems, which are formed in jointed rock masses. In the present study, a three-dimensional (3D) DDA method was conducted to study the toppling failure mechanisms of rock slopes by introducing the global contact theory. Considering dynamic equilibrium conditions, the analyses of toppling slopes were performed and the corresponding formulations were derived. The algebraic and mechanical computation of the global contact theory was illustrated and implemented into the 3D DDA method. An experimental apparatus for studying the toppling process of blocks was developed and a series of laboratory experiments were carried out for different block distributions under different conditions. By comparing with the results of the analytical methods and laboratory experiments, the accuracy of the 3D DDA method was verified. Numerical examples, including a classical toppling slope, an ideal mountain slope, and a real toppling case were analyzed to further research the toppling failure mechanisms. The results revealed that the 3D DDA method can effectively predict slope instability and simulate the failure process of toppling slopes. The results of the dynamics-based formulations, experiments and 3D DDA enrich the instability conditions of slope-toppling. Moreover, the general phenomena and laws of the toppling failure were presented.