Research On Urban Space Unified 3D Modeling Technology

Generally speaking,3D urban spatial modeling currently is only biased to research on visualization methods of geospatial objects and establishment of 3DGIS platform,or simulate the geological body and geological phenomena in urban geoscience space for supplementing traditional 2D geological information expression and improving the results of urban geological survey,which rarely focuses on research and application of total urban space.Some scholars who considered the importance of geological structure have done a lot of research on unified 3D modeling of urban space and spatial-data model,but these help little to handle the rapid reconstruction of complex geological structure of large city scale and management of multi-source and heterogeneous model data.In response to these problems,this thesis,based on 3D urban geological survey,proposes a new method of urban space unified 3D modeling,which not only makes sure of the rationality and beauty of urban planning and construction,but also stability and safety of city’s underground geological environment.This thesis divides urban space into geographical and geoscience space with surface as the boundary.As for geospatial 3D modeling,this thesis has studied several objects modeling method and selects the most suitable one for modeling,besides,the optimization of 3D models and the key technology of the feature and terrain matching;In the part of geoscience spatial modeling,this thesis has studied using industry-leading 3D modeling technology to efficiently and reasonably complete urban geological modeling,and summarizing technical methods and processes of structural modeling based;In the aspect of spatial model integration,this thesis focusing on the organic combination of multi-source heterogeneous data has transformed the geological model data into the general standard format of 3DGIS platform to realize the integration of urban space and do correlative analysis and application finally.The research contents of this thesis mainly includes the following aspects:1)This thesis has studied and compared several current 3D urban landscape modeling techniques,and selects the most suitable one to reconstruct buildings,roads and ancillary facilities in urban geospatial space;2)Based on TIN model,this thesis has used elevation sampling point data to construct the 3D city terrain,and used texture mapping technology to overlying orthophoto image of the same range to complete the creation of terrain model;3)Introduced the effect of models to terrain,this thesis has researched the key technology of matching between ground models、roads and terrain;4)In the aspect of 3D urban geological modeling,this thesis has used the professional geological modeling platform SKUA-GOCAD to model urban geologic body and applied its semi-intelligent modeling workflow to field of urban geology;5)In the aspect of data conversion,this thesis has analyzed the organization structure of Model3 d data and compared with the Geo3 DML main modules,besides,established the corresponding relationship between these two data structures.this thesis has completed conversion from Model3 d data to Geo3 DML format by data reading and writing operation finally;6)This thesis has used MapGIS10 platform to carry out urban space’s integrated display and model data management,and used analysis tool to carry on several spatial analysis of 3D space.The innovation of this thesis is mainly reflected in: using SKUA-GOCAD to solve rapid construction of large-scale complex geological structure model and carring out the data conversion of Model3 d through Geo3 DML to make up for the deficiency of current 3DGIS platform in solving urban geological modeling.The experimental results show that this method is practical and extensible.