复杂滑坡三维离散建模方法及其在茂县滑坡中的应用

THREE-DIMENSIONAL DISCRETE MODELING METHOD FOR COMPLEX LANDSLIDE AND ITS APPLICATION IN THE MAOXIAN LANDSLIDE

针对3DEC软件在建立滑坡模型前处理功能上的不足,本文提出了一种基于MATLAB平台构建复杂滑坡数值模型的前处理方法。以滑坡发生前后的地形数据为基础,通过Distmesh工具箱进行滑坡区域的三角网格剖分与高程插值,生成三棱柱体构建滑床与滑体。同时借助Multi-Parametric Toolbox几何库中的函数生成Voronoi多面体来模拟滑坡路径上的基底物质,编写相应函数以获取块体的拓扑信息,并依据3DEC的语法规则将其转化输出为3DEC可读取的命令文本文件,实现了复杂滑坡模型的快速建立。最后以四川省茂县新磨村滑坡为例,详细叙述了滑坡数值模型的建模步骤。数值模拟结果表明,该方法建立的模型能够较好地重现滑坡运动过程、沿程铲刮现象以及最终堆积形态,验证了该方法的可行性和实用性。

The weakness of 3 DEC software in the pre-processing of building the landslide model limits its application.As for this,this paper proposes a new modeling method for complex landslide with MATLAB.Firstly,the terrain maps before and after landslide are used as data sources.Using Distmesh toolbox to triangulate the landslide area,the triangular prisms are generated through an elevation-based interpolation algorithm and to reconstruct the sliding bed and the sliding mass.At the same time,the base material on the sliding path is modeled with Voronoi polyhedrons generated with Multi-Parametric Toolbox.Then,some functions are written to obtain the topology information of these blocks.According to the syntax rules of 3 DEC,it is transformed into a command text file that can be received by 3 DEC.By this way,the complex landslide model can be established quickly.Finally,taking the Xinmo Landslide in Maoxian County of Sichuan Province as an example,the modeling steps are described in detail.The result of numerical simulation shows that the model established by this method can well reproduce the sliding process,the entrainment of substrate material and the final deposition.The feasibility and practicability of this approach is verified.