Viaduct is the most important express for the central area in Chengdu. Viaduct management unit faces a huge challenge in road management. Firstly, inspector lacks model and useful tools, the problem location can only be described by words, which is very hard for technical staff to find the problem location; secondly, millions of viaduct materials cannot match with the viaduct, bringing troubles of problem locating, materials finding.
In order to realize high efficient management of viaduct, the management introduced BIM technology, providing overall planning on viaduct. The plan is based on BIM application on CATIA+ENOVIA, integrating SuperMap GIS system, after series of work of digitalization modeling, material uploading, business soring. Finally, a viaduct management information system with routine maintenance, digitalization transfer, monitoring testing management, road maintenance management, GIS model, sync and authorization has been developed.
Currently, spatial data management and location function based on GIS, inspector can precisely locate with mobile devices, quickly collect problem data and upload to the cloud; the management view and distribute repair mission through mobile devices. Technical staff can view repair mission and respond in the system. The management can view maintenance status in the system.
Figure 1 Viewing BIM components and problem information in system
Figure 2 Technical staff checking using mobile device.
BIM and GIS integration effectively realizes informatization, visualization, mobilization in the network, realizing paper-free. The system brings high-efficiency, high level, high quality and low cost maintenance and management.
The case mentioned above is a representative of GIS + BIM merging. In recent years, in order to realize the merging of BIM and 3D GIS, SuperMap increased investment in R & D, bringing breakthroughs in data docking, multi-data integration, smooth performance, rich function, multi-terminal, etc., forming the full-angle technical solution from data importing to industrial application.
1. Data docking problem
There are multiple BIM software as well as multiple formats. SuperMap provides convenient BIM importation mechanism: for the mainstream software Autodesk Revit, it provides SuperMap Export plugin, which supports exporting BIM into SuperMap platform model dataset, realizing model light weighing; for the CATIA export plugin, SuperMap platform can read CATIA model and attribute information directly; In addition, SuperMap iDesktop supports multiple Intermediate formats (FBX, IFC, DAE, X, OBJ, 3DS, OSGB/OSG), it also provides intermediary method to import SuperMap platform in 3ds max 2014.
2. Multi-data integration, deepening depth of BIM application
Basing on cutting-edge oblique photogrammetry GIS application solutions, SuperMap combines oblique photogrammetry model and detailed BIM model, realizing integrating measuring-constructing-geographic space, forming 3D scene from outdoor to indoor, from above to underground.
Figure 3 detailed matching between BIM and terrain
3. Optimization measurements to ensure the smoothness of performance
BIM is the full information expression of building with very detailed model, details mean very massive amount of data, SuperMap GIS provides multiple optimization measures: Firstly, light weighing of BIM, the number of simplified triangle can decrease by 40%-80%; Secondly, using instantiation technology to improve rendering efficiency; finally, storing the multi-level LOD scene cache into BIM model to display different level of detail model at different distances to lower the display card pressure.
Figure 4 Display effect comparison between number of triangles decreased by 37%
4. Rich analysis function, aiding digging BIM application values
In the practical function layer, SuperMap GIS provides rich application functions for BIM. In the real application, GIS location services and spatial analysis have been fully utilized, BIM will create wider applications.
Provides basic functions like attribute analysis, spatial analysis, spatial measurement, etc.
Provides universal GIS functions like visibility analysis, inter-visibility analysis, collision analysis, buffer analysis, etc.
Acquires profile surface from any angle, model can be measured and spatially queried by ID.
Provides building construction simulation process, BIM functions like designating storey/component displaying.
Supports operations between BIM and other model to make sure BIM accurately match with oblique photogrammetry model, TIN terrain.
Provides animation and particle effect, realizing staff checking simulation, car passing, etc.
Figure 5 BIM profile acquisition
Figure 6 BIM fire escape simulation
5. Multiple cloud & terminal integration for management/maintenance
Currently, SuperMap PC terminal (iDesktop and iObjects), Web terminal (iClient3D for Plugin/WebGL), Mobile (SuperMap iMobile for Android/iOS) all support BIM applications, supporting different requirements from different users.
Basing on cloud & terminal integration technology series, SuperMap also provides ‘Cloud + Terminal’ integration BIM operation/management solution: with the help of pre-process operations on BIM like analysis, format transforming, light weighing, etc. from cloud, web terminal and mobile terminal are used for front-end displaying platform, which allows accessing 3D cloud services efficiently at any time and providing rich BIM maintenance/management with rich analysis functions.
Figure 7 BIM operation management based on mobile terminal
SuperMap GIS will keep BIM industry as core and put more efforts in seamless docking with BIM formats, loading bigger BIM data, providing deeper formats, merging BIM and other spatial comprehensive applications, advancing GIS+BIM merging, with the goal of more effective, practical industrial solution.