【作者】 胡刚；

【导师】 邓敏；

【作者基本信息】 中南大学 ， 地图学与地理信息系统， 2011， 硕士

【摘要】 地质体三维可视化是地质工程中急需解决的一个热点问题。它是指以适当的数据结构建立模拟地质体特征结构的数字模型,然后利用计算机可视化技术将数字模型以三维真实感图形的形式予以表现。利用三维可视化的结果可以将地质体的形态构造直观形象的展现在用户和相关的专家面前,最大限度地增强人们对地质分析的准确性和直观性,使之做出符合实际的地质现象分布和变化规律的施工方案和工程设计,从而减少人们对地质问题认识的滞后性、盲目性以及地下工程的施工设计所面临的巨大风险性。本文通过对当前国内外地质体三维可视化的理论和方法的研究与总结,以国家863项目“城市浅层地质勘探及三维地质成像技术”为支撑,重点研究了以下内容：1)通过分析VTK (Visualization Toolkit,可视化工具包)自身的数据结构及文件格式特点,在不影响可视化效果和空间分析的前提下,对现有采用以广义三棱柱(Generalized Tri-Prism,简称GTP)为体元的建模方法进行了简化,使之可以更加快速地建模和可视化操作。2)对传统的基于钻井数据的三维地质建模方法做了一些改进,其中,在构建地表面主-TIN网时,添加了对三角网所有三角形的顶点进行排序的步骤,使GTP体元可以自动、快速地剖分成四面体。3)结合本文提出的GTP模型结构和建模方法,采用面向对象的方法,设计数据结构,基于钻井数据对地质体进行三维建模,并生成VTK格式的数据。最后,根据用户需求,按照软件工程的方法,在Qt的平台下,以VTK为图形开发工具包,开发了一个地质体三维可视化系统,实现了地质体的真三维显示和一些常用的空间分析和操作功能。同时,利用该系统,对本文建模方法的实际建模效果进行了展示和验证,取得了预期的效果。通过本文对地质体的三维建模与可视化方法的研究,为地学领域的三维地质建模及可视化系统软件的研发提供了一种新的思路和方法。更多还原

【Abstract】 3D visualization of geological bodies is a hotspot issue to be solved urgently in engineering geology. Such visualization aims to construct a digital model with the structures of the features of geological bodies, with proper data structures and then demonstrating the model in a three dimensional graph with the application of visualization technology of computer. The result can exhibit the structural configuration of geological bodies to users and relevant experts visually, maximizing the accuracy and reliability of their analysis of the bodies. Therefore, they can work out construction schemes and engineering designs in conformity with distribution and change rules of geological phenomena, and reduce hysteresis and blindness in their recognition of related problems as well as risks in designing and construction of underground projects.Through review and summary of theories and methods of 3D visualization of geological bodies both home and abroad, the paper mainly conducts research into the following areas with the support of the 863 program--"Geological Exploration at Shallow Depth in Urban Areas and 3D Imaging Techniques".1) Through analyzing the features of the data structure and the file format of VTK without affecting visualization effects and spacial analysis, the paper simplifies the topological relationship needed to be maintained by the existing modeling method with the voxel of Generalized Tri-Prism (GTP), to accelerate the process of modeling and visual operation.2) The paper improves the traditional 3D geological modeling methods based on drilling data. For example, the author added the sorting procedures of each vertice of triangulation while constructing main TIN net on surface to disect the GTP voxel into TEN automatically and rapidly.3) Based on the GTP structure and modeling methods, the paper, in an object-oriented way, designs data structure, practices 3D modeling to geological bodies on the based of drilling data and generates data of VTK format. Finally, according to users’demands and based on the software engineering method, the paper, with Qt as a platform and VTK as a graphics development toolkit, develops a 3D visualization system of geological bodies, realizing true 3D display of the bodies and some common spacial analysis and operation. Meanwhile, the author used the system to verify and demonstrate the proposed modeling method of the paper and get the expected result. Thus the paper provides a new thought and method for the research and development of 3D geological modeling and visualization system software.更多还原