复杂岩质高边坡三维地质建模及虚拟现实可视化

结合复杂岩质高边坡工程三维地质建模和可视化需要,通过综合分析国内外在计算机图形学领域对描述空间拓扑关系的常用三维数据结构,提出基于半边B-Rep和裁减NURBS数据结构的边坡三维地质建模方法,实现具有复杂地质条件和基础洞室群的边坡工程三维模型拓扑关系的快速、准确建立,为边坡工程三维地质可视化提供高质量的几何数据和拓扑关系信息。分析计算机可视化技术的发展趋势和虚拟现实技术的特点,论证应用桌面级虚拟现实技术的X3D规范,实现边坡工程地质可视化的可行性。鉴于X3D灵活的场景交互和对复杂NURBS几何造型的支持,实现基于X3D的边坡工程虚拟现实场景的实时动态可视化、虚拟现实场景对象的可视化交互式查询。以锦屏一级水电站左岸边坡工程为例,给出三维地质虚拟现实可视化在边坡开挖进度模拟和地质超前预报、边坡地质条件可视化查询、边坡安全监测断面地质条件解析、边坡安全监测系统可视化查询和综合分析等方面的应用,为三维地质虚拟现实可视化方法在其他工程领域的应用拓展提供参考。

THREE-DIMENSIONAL GEOLOGICAL MODELING AND VISUALIZATION BASED ON VIRTUAL REALITY FOR COMPLICATED HIGH ROCK SLOPE

In order to achieve three-dimensional geological modeling and visualization of complicated high rock slope engineering，a new method of three-dimensional geological modeling and visualization based on data structures of half-edge B-Rep and trimmed NURBS is proposed. Through making comprehensive analysis of common data structure for describing the space topology in the field of computer graphics，rapid and accurate establishment of topological relation of three-dimensional geological model for rock slope engineering with complicated geological conditions and cavern groups is achieved；and the high-quality geometrical data and topological relation information for the geological visualization of slope engineering are provided. By analyzing the development trends of computer visualization technology and the characteristics of virtual reality technology，the feasibility of applying X3D specifications based on desktop virtual reality technology to achieve the slope geological visualization is demonstrated. According to the flexible scene interaction and support for the complicated NURBS geometric models of X3D，the real-time dynamic visualization of slope three-dimensional geological virtual reality scenes and visual interactive query in virtual reality scene objects based on X3D is realized. Finally，taking the left abutment slope of Jinping I hydropower station for example，the applications of three-dimensional geological visualization based on virtual reality to slope excavation progress simulation，geological prediction，visualization query of slope geological conditions，geological analysis of slope safety monitoring section，visualization query and integrated analysis of slope safety monitoring system and so on are given. These may provide reference for the application of three-dimensional geological visualization based on virtual reality to other engineering fields.