Research on BIM + GIS full element 3D model processing technology

In view of tunnel engineering characteristics, such as "high ground stress, high gas concentration, many fault-fracture zones/unfavorable geological conditions/groundwater corrosiveness types and large buried depth," research on key tunnel digital construction technologies was performed to integrate engineering construction, geological investigation report and geographic information 3D models into 3D visual data information. In the research, large BIM models are lightened with the mass cutting method based on the combination of BIM and GIS of the Cesium engine. A heterogeneous model integration method is proposed to convert BIM into FBX format. Then FBX is converted into 3DTiles standard format suitable for Cesium engine, thereby combining BIM and GIS technologies. In the end, a B/S architecture-based case is demonstrated, which solves the tunnel safety warning problem by realizing a visual tunnel safety warning. Site data is loaded in the full element 3D model in a real-time manner with the combination of Cesium engine and tile & lightweight technologies to achieve back-end "data middle platform" integrated operation and 1:1 mapping of front-end "digital construction site" and "real construction site," which has reference value to the application of BIM + GIS technologies in the railway tunnel industry.