基于Voronoi节理模型的碎裂岩边坡稳定性分析

Stability analysis of broken rock slope based on Voronoi joint net model

岩体结构是控制边坡稳定性的主要因素,因此无论用何种方法分析其稳定性时,都不能忽视岩体结构的存在。本文在简要介绍Voronoi图基础上,针对碎裂岩边坡建立了基于Voronoi图的节理网络有限元模型,通过有限元强度折减法分析了其破坏方式和稳定性,同时对比了该模型与碎裂岩边坡均值假设、不考虑节理条件下的计算结果。结果表明:相比于均质模型,Voronoi节理模型对边坡坡度的变化更为敏感;利用均匀连续介质模型和Voronoi节理模型对同一边坡的模拟结果差异不大,破坏模式都是圆弧破坏剪切破坏;Voronoi节理模型首先由坡顶开始产生最大位移,随后沿着坡面一定深度范围内向坡脚发展,而均质模型首先在坡脚产生最大位移,随后在坡体内部由下向上形成贯通的圆弧形破坏面。同时指出了利用该模型时应注意的一些问题。

Rock mass structure is the key factor controlling the slope stability which should not be ignored no matter which method is used to evaluate slope stability. On the basis of introducing Voronoi model,FEM model with Voronoi joint net is built up for the broken rock slope,and thus the stability status and failure mechanism is analyzed by using FEM shear strength reduction method,in the meantime,FEM model under the assumed condition of homogeneous medium for the broken slope is also reviewed. The results show that the Voronoi joint model is more sensitive to the change of slope than the homogeneous model. The simulation results of the same slope with the uniform continuous medium model and the Voronoi joint model are not very different. Voronoi joint model of maximum displacement was first start from the top,then along the slope surface slope toe development within certain depth range,and homogeneous model first maximum displacement in the slope foot,then inside the slope formed from bottom to top through the circular failure surface. Also,some questions about the application of Voronoi joint net for the broken slope are discussed.