Integration of 3-D GIS and highway CAD

For the purpose of promoting the application of 3-D GIS to the highway plan, design, construction and management, authors presented the integrating methods of 3-D GIS and highway CAD. At first, the data integration of 3-D GIS and highway CAD was analyzed; the 3-D route surface model and the 3-D construction solid model were integrated into 3-D highway GIS database. Based on the simplification of the 3-D models, authors discussed the real-time and dynamic visualization technology of 3-D highway GIS in the circumstance of vast database. The architecture of 3-D highway GIS was also presented. Finally, authors discussed the application prospect of 3-D highway GIS for the geometrical route design and the facility management et al.