基于三维激光扫描技术的复杂三维地质体建模方法

摘要

FLAC3D平台下前处理阶段复杂地质体三维数值计算模型的建立一直是岩土工程数值模拟工作者面临的难题,而三维激光扫描技术在获取复杂物体的精细空间数据的方面具有独特的优势.因此,本文提出以逆向工程为过渡平台实现复杂三维地质体FLAG3D数值模型的构建.利用三维激光扫描技术精细几何数据的获取功能,对复杂三维地质体空间形状几何信息进行提取;利用Geomagic Studio良好的点云数据处理及曲面建模功能,准确地重构了复杂地质体的CAD曲面模型;利用Hypermesh强大的几何处理能力及网格划分能力,将复杂地质体的CAD曲面模型进行实体化和网格化;最后由FLAG3D软件内嵌的Fish语言编制的文件转换为FLAC3D能够识别的文件格式,从而实现了该软件前处理过程中复杂三维地质模型的高效、精准的建立.结合工程实例,对该方法的可行性与仿真效果进行了检验.结果表明该方法具有方便、快捷、合理且实用性强的优点.%In the platform of FLACTM software,how to build the three-dimensional models of complex geological bodies is always a difficulty encountered by many numerical simulation operators.On the other hand,the threedimensional laser scanning technique presents a unique advantage in obtaining the fine spatial data of complex objects.Therefore,by the aid of reverse engineering,a new modeling method of complex geological bodies in FLAC3D platform is proposed.The accurate spatial and geometric information of complex geological bodies is firstly obtained by employing three-dimensional laser scanning technique.The point cloud data describing surface characteristics of complex geological bodies is processed and its surface model is then reconstructed in CAD format.Using the formidable geometry cleanup and mesh generation function of Hypermesh software,the surface model is transformed into threc-dimensional finite element model.The node and element information can be translated into the format which can be received by FLAC3D.According to the above processes,the model data for FLAC3D is generated and the refined model of complex geological bodies is created in the pre-processing of FLAC3D.the feasibility and practicability of this approach is verified by combining practical project.