Integrating Building Information Modeling (BIM) and Geographic Information Systems (GIS) would yield a formidable tool that would accommodate both planners and developers. These unique tools are both from different domains i.e. BIM was developed for the Architecture, Engineering, and Construction/Facility Management domain while as GIS serves the geospatial industry. The integration can be operated on two levels, the data level and at the application level. The representative data format for BIM is the Industry Foundation Classes (IFC). In the GIS framework, there are two main data formats available, City Geography Markup Language (CityGML) and shapefile. Integration of BIM and GIS involves transformation of IFC to shapefile format. Currently, few options are available for users to effect this transformation. In particular, ArcGIS uses the Data Interoperability (DIA) extension to expand the range of supported data formats. However, DIA is known for its poor performance in the shapefile transformation process. Consequently, it is evident that there lacks a perfect approach to perform the IFC/shapefile transformation.
Considering the wide use of shapefile in application-oriented research, it is necessary to improve the quality of the transformation in terms of the geometry and semantics. To this end, a group of researchers from the Curtin University in Australia: Dr. Junxiang Zhu and Dr. Peng Wang, in collaboration with Professor Xiangyu Wang and Dr. Mi Jeong Kim at the Kyung Hee University, and Dr. Zhiyou Wu at the Chongqing Normal University developed an Open-Source Approach (OSA), in which the geometric information in IFC was retrieved through the spatial structure of IFC, i.e., IFC-Tree, and converted into shapefile by developing an automatic multi-patch generation algorithm (AMG). The researchers focused on geometric information extraction because geometric information is the most fundamental information needed for most studies for visualization or analysis purposes. Their work is currently published in the research journal, Automation in Construction.
The researchers presented a methodology including the raw geometric information extraction, geometry coordinate system transformation and the development of an automatic multi-patch generation algorithm. The scholars then implemented their experiment which was followed by a discussion on the differences between the DIA and OSA, the eﬀect of ring order and extrusion direction on the generation of multi-patch.
The authors observed that the transformation of IFC to shapefile could be achieved with opensource technology and was more stable and efficient than that of the DIA. They also noted that the transformation was unidirectional from IFC to shapefile in terms of geometry. Moreover, it was reported that by using the AMG, a qualified multi-patch could be generated regardless of the initial ring order and extrusion direction.
In summary, Junxiang Zhu and his colleagues demonstrated the application of an Open-Source Approach (OSA) -an open 3D data format popular in geospatial science- to transform the geometry of IFC to shapefile. Consequently, the spatial structure of the IFC data format was thoroughly investigated and a customized multi-patch generation algorithm developed to create multi-patch automatically from specific parameters. Overall, in an interview with Advances in Engineering, Junxiang Zhu pointed out the OSA can link BIM and GIS in a more stable and efficient manner by enhancing the data transformation from BIM to GIS.
Junxiang Zhu, Xiangyu Wang, Peng Wang, Zhiyou Wu, Mi Jeong Kim. Integration of BIM and GIS Geometry from IFC to shapefile using opensource technology. Automation in Construction, volume 102 (2019) page 105–119.Go To Automation in Construction