# Geotechnical Property Modeling and Construction Safety Zoning Based on GIS and BIM Integration
## 1 Introduction
### Previous BIM-GIS Integration  
The domain of GIS provides information about existing assets at a different time in a large geographic area, while BIM is merely used for specific construction projects. BIM and GIS were developed for different fields of application. The integrated application of these two systems in the architecture, engineering, and construction (AEC) industry can contribute widely to the practices and theories of sustainable infrastructure [34]. Even though the two systems have overlapping feature, however, it is still very difficult to integrate the system, and transferring the GIS data into BIM is very challenging because of the lack of tools that can successfully manage the BIM data in GIS, differences in data representation schemas, and poorly defined BIM semantics. Three kinds of methods have been adopted in the literature to integrate the two systems [52]: (1) BIM data integration into GIS; (2) GIS data integration into BIM; and (3) integrate BIM and GIS both into a new platform. Most of the studies have focused on the integration of BIM data into GIS. A 3D semantic building model dedicated to urban development was developed by transferring data from BIM industry foundation class (IFC) to GIS (CityGML) [53]. Three software components were developed to integrate BIM information into GIS about geospatial environment focusing on the site selection and fire response management [54]. In another study, a multi-purpose geometric network model (MGNM) was established to facilitate indoor and outdoor connection for emergency response and pedestrian route planning. Safe route planning in today's busy urban areas needs comprehensive and consistent information about the existing environment. An ontology-based framework was developed for safe routes to school that collects information from the BIM model and integrated with GIS, which can effectively evaluate the existing walkability [55]. The IFC semantic information was integrated into a CityGML extension called GeoBIM, which concludes the technical transfer of IFC semantic information into CityGML [56]. BIM and GIS have been integrated for indoor spatial analysis. Autodesk Revit was used to model the IFC-based BIM model and exported to ArcGIS using the data interoperability tool [57]. The above studies have focused on the integration of BIM to GIS where information from the BIM model was extracted and integrated with GIS for the different application that shows very effective and positive results. However, there are studies in the literature which integrate GIS information into BIM as GIS contain information about existing or captured facilities in a different time. For example, GIS contains data about the environmental condition that was connected to the BIM for the climatic condition of building analysis [50]. Moreover, GIS has been used to map the supply chain process and a plugin was developed in the BIM, which integrates BIM and GIS that optimizes the construction supply chain management (CSCM) [44]. Also, some studies combine BIM and GIS into a new platform to enhance their abilities and facilitate the construction process. BIM and GIS were connected into a new platform for the district information model (DIM). Revit software was used as a BIM tool and ArcGIS as a GIS tool, which was integrated into Infrawworks preserving geometrical and semantic information [58]. BIM and GIS integration has great potential from various aspects that can facilitate to better visualize contextual GIS information in BIM environment, detailed 3D city models, linkage of geography and geometrical information, integration of surface and sub-surface information, and the spatial capability of GIS can support the whole life cycle of the project. However, the application of BIM and GIS integration are still limited and its use is not fully utilized for the geotechnical modeling and safety zoning for the construction projects.