The Research Of Tunnel Automatic3D Modeling And Visualization

Tunnel3-D modeling and visualization of the study was to investigate the structure of ofusing ArcGIS Multipatch data automatic modeling of3-D tunnel. Structure of Multipatch datato establish the3-D data model is a vector data model, but this data structure to establish a3-Dmodel, can not be edited, so use this method to create the data model must complete aone-time, including the connection between the tunnel and the corner smoothing.This paper studies the content and consists principally of the following:(1) pre-processing of the data is extracted from a large number of raw data for automatic3-D modeling of data, including data and neutral point of the center line of the tunnel data, andthe midline data and neutral point data in ArcGIS convert SHP format data stored in the mdb,conducive to the management of the data.(2)3-D spatial data model, its main task is to establish the spatial relationship betweenthe3-D spatial data model, a true reflection of the tunnel, full of internal characteristics of thetunnel. Used Multipatch data model for such a model, the establishment of point data and linedata spatial topological relations (line-arc-point).(3) tunnel3-D modeling algorithm is to use the principle of buffer analysis generated onthe boundary line of the tunnel, the tunnel line, a series of nodes and node by multiple arcsform the arc. Inserted by section node the tunnel boundary must point feature generated by amultifaceted piece (Multipatch) data model, to achieve the3-D surface model of the tunnelautomatically created.(4) smoothing model is in the corner of the tunnel and the tunnel at the intersection ofstep increase, smooth stitching of the tunnel turns and intersections.3-D model image,intuitive, and can be a direct reflection of the spatial location of the tunnel, this result has animportant role in guiding the underground tunneling and engineering.Finally, the C#language ArcGIS Engine platform for secondary development, make fulluse ArcGIS Engine provides basic GIS functionality and a rich interface, programming bufferanalysis and cross-section of the node insert methods to achieve automatic modeling for3-D tunnel to provide a solid based on3-D model of the tunnel by using ArcScene achievevisualization. Tunnel3-D automatic modeling and visualization system to achieve scientifictunnel data management, information technology, to provide the highest level of service,which provides the decision-making services for the tunnel project.