Constraints for Improving Information Integrity in Information Conversion From CAD Building Drawings to BIM Model

Computer Aided Design (CAD) systems play an important role in the production of building designs that are used to assist building constructions. Thus, CAD building drawings contain a large amount of building data important for indoor navigation and other related analysis which are often done in BIM (Building Information Modeling). Therefore, the conversion of CAD-based building data to BIM is necessary to make the data in CAD useful for these applications. However, when mapping to the BIM model, there are semantic ambiguities which will have an important impact on the subsequent analysis of the information converted from CAD. This paper addresses these ambiguity problems by first examining the building information represented in CAD drawings and the mapping relationships between the building information in CAD drawings and that in BIM. Once these relationships are established, the semantic ambiguities existed in the mapping were identified and then corresponding constraints were developed to address these ambiguities. The experiment results show that the approach described in this paper can effectively eliminate the semantic ambiguity of the mapping from CAD to BIM and the converted BIM model can effectively support subsequent analysis.