The document discusses two scenarios for implementing building information models within geographical information systems: 1. Real-time visualization of construction projects, which would export an abstracted building geometry model from IFC files to a GIS using a web service and store data transiently for visualization. 2. An emergency fire response software, which would import IFC files directly due to data needs, store building data persistently in a spatial database, and use advanced visualization tools beyond standard GIS capabilities. Further research opportunities include technical implementations of 3D object representation in spatial databases and visualization of 3D buildings in GIS.

1. TOWARDS THE IMPLEMENTATION OF THE BUILDING INFORMATION MODELS IN GEOGRAPHICAL INFORMATION SYSTEMS Umit Isikdag, Prof.Ghassan Aouad Dr. Jason Underwood, Dr. Nigel Trodd * University of Salford *Coventry University

8. INFORMATION MODELLING IN THE CONSTRUCTION INDUSTRY

11. What is an Industry Foundation Classes (IFC) Model IFC is an object oriented building information model that contains high amount of geometry and attribute information about a building Roof: Geometry: Triangle Material: Concrete Will be built on:10.1 2 .2004 Cost:1000£ Door: Geometry: Rectangle Material: Wood Will be built on:10. 11 .2004 Cost:100£

12. The Structure of IFC models

13. Structure of STEP Description Methods EXPRESS, EXPRESS-G IDEF1x ,NIAM, Integrated Resources Common Model Subsets Application Protocols Meta Models Application Reference Model (Defined by EXPRESS-G) Application Interpreted Model (EXPRESS) Implementation Methods Physical Files Structures(21) File Access Methods(22) Conformance Test assesses the implementation

14. IFC Schema : The Meta Model Meta Model file is called IFC Schema Meta Model file holds the IFC entities IFC entities contain descriptive information about IfcObjects. Meta Model is defined by EXPRESS The meta model file has the .exp extension ENTITY IfcOrganizationRelationship; Name : IfcLabel; Description : OPTIONAL IfcText; RelatingOrganization : IfcOrganization; RelatedOrganizations : SET [1:?] OF IfcOrganization; END_ENTITY;

15. IFC Physical File Physical Model file is called IFC file Physical Model file holds the IFC objects Physical Model is defined by STEP Standard Part 21 The physical model file has the .ifc extension #42 = IFCSHAPEREPRESENTATION (#26, 'Axis', 'Curve2D', (#41)); #43 = IFCCARTESIANPOINT ((0., 0.)); #44 = IFCCARTESIANPOINT ((2000., 0.)); #45 = IFCCARTESIANPOINT ((1760.000005364418, 239.999994635582)); #46 = IFCCARTESIANPOINT ((-239.999994635582, 239.999994635582)); #47 = IFCPOLYLINE ((#43, #44, #45, #46, #43)); #48 = IFCARBITRARYCLOSEDPROFILEDEF (.AREA., $, #47);

16. IFC Information Exchange Architectures

17. Information Exchange with IFCs IFC file (STEP-P21) XCAD YCAD Level1:Data sharing between applications using building information models as physical files

18. Information Exchange with IFCs Level 2: Accessing the IFCs through APIs IFC File (STEP-P21) IFC API SDAI API XCAD Client B YCAD Client A

20. Express Databases Express (ISO10303) Database Management System (ODBMS) IFC Meta Model (Schema) (ISO10303) IFC File (ISO10303-P21)

22. Alternative types of architectures Yes Yes, Database Schema Yes/No No Need for the schema No Yes (DB API)/No RDBMS ODBMS Storing IFCs in RDBMS / ODBMS Yes Building.ifc Accessing IFC with APIs EDBMS Building.ifc Data stored in form of.. Yes (DB API) Storing IFCs in EDBMS No IFC Physical File Exchange Need for an API to get information Architecture Type

23. A brief overview of GIS architectures

24. A brief overview of GIS architectures Application Component Pool Spatial Database Data Files Rst+ Vec+ Std (inc.GML) Web Services Components (WMS,WFS) Data Connectors Data Analysis Tools Data Converters Visualisation & Interaction

25. Analysis of the technology

27. Scenario 1 R eal time visualisation of construction operations in 3D

37. Scenario 2 Emergency Fire Response Software

47. Summary