Abstract: Conceptions and characters of the existing 3D spatial data models were systematically analyzed and classified. To meet the special requirements of 3D modeling and visual analysis in urban underground spaces, two kinds of data models that suited to spatial structure information and spatial property information respectively, were designed and implemented. To express the complicated geometric structure of geological entities, underground structures and pipelines, a 3D vector data model, which is based on boundaryrepresentations and topological relationships, was developed. 3Draster structure model is used to modeling and visualization physical and chemical property parameters inside geological bodies. To meet the demand of the geological property modeling, a conversion approach of 3D vector data model to 3Draster structure model is implemented.

Key words: underground space information, data model, 3D geology modeling, visualization , digital city, underground space information, data model, 3D geology modeling, visualization