贵州三叠系地层多分布含软弱夹层顺层岩质滑坡，该类滑坡具有破坏性强、滑移机制复杂、治理难度大等特点。以贵阳市西二环滑坡为例，通过野外地质调查、理论分析和离散元数值模拟等方法，探究该类滑坡成灾机理和失稳运动演化过程。结果表明：西二环滑坡主要由白云质层状碎裂岩体组成，渗透性和保水性较好，呈现“海绵体”结构，持续性降雨是该滑坡诱发的直接原因；该滑坡首先由前部滑体剪出，且逐渐向上牵引，随后滑体后缘张拉裂隙进一步发育，在重力作用下导致滑移-拉裂破坏，模拟结果与实际情况基本吻合；西二环滑坡可分为4个变形失稳阶段：自然溶蚀裂化-开挖卸荷扩展-饱水弱化剪切-缓慢滑移堆积。研究结论对于贵州三叠系含软弱夹层顺层岩质滑坡的成灾机理分析和工程防治具有一定的参考意义。

Most of Triassic strata in Guizhou are distributed with bedding rock landslides with weak interbeds, which are characterized by strong destructiveness, complex slip mechanism and difficult treatment. Taking the West Second Ring landslide in Guiyang City as an example, the disaster mechanism and instability evolution process were explored by means of field geological investigation, theoretical analysis and discrete element numerical simulation. The results show that the West Second Ring landslide is mainly composed of dolomitic layered cataclastic rock mass with good permeability and water retention, showing a "sponge" structure, and continuous rainfall is the direct cause of the landslide. The landslide is first cut out by the front sliding body and gradually pulled upward, and then the tensile cracks at the trailing edge of the sliding body developed further, which led to slip-tensile crack failure under the action of gravity. The simulation results are basically consistent with the actual situation. The landslide in West Second Ring Road can be divided into four stages of deformation and instability: natural dissolution and cracking, excavation and unloading expansion, saturated and weakened shear, and slow sliding and accumulation. The conclusions have certain reference significance for the disaster mechanism analysis and engineering prevention of Triassic bedding rock landslide with weak interlayer in Guizhou.