Faculty of Civil, Geo and Environmental Engineering Chair of Computational Modeling and Simulation Prof. Dr.-Ing. André Borrmann Faculty of Architecture Chair of Architectural Informatics Prof. Dr.-Ing. Frank Petzold BIM and the public sector 27. July 2018 Report Advanced Topics in Building Information Modeling Gergana Popgavrilova Advanced Topics in Building Information Modeling Table of contents 1. Introduction .................................................................................................................... 3 2. BIM Policies ................................................................................................................... 8 3. Trends for development .................................................................................................18 4. Conclusion and Outlook ................................................................................................19 Chair of Computational Modeling and Simulation Seite 2 Chair of Architectural Informatics Advanced Topics in Building Information Modeling 1. Introduction 1.1. Interoperability Data interoperability is a key to achieving worldwide standardization of BIM methods und usage. An open-source approach based on open standards and workflows, the so called OpenBIM, is the base for collaborative design, realization and operation of buildings. OpenBIM was developed by leading software vendors using BuildingSMART data Model and aims to support a transparent workflow, allowing user to design and maintain quality project data regardless of the software tool they use. By avoiding multiple input and consequential errors OpenBIM provides enduring project data throughout the asset life- cycle. Open data standards achieve common language and empower the exchange of relevant data between software applications and thus an efficient communication among project members. There is also a great financial incentive to use open BIM standards - once information transfer is standardized, the cost of extracting it again and making quotes is greatly reduced. Reaching industry wide consensus on open standards is critical, hence it is important to demonstrate agreement on standards use not project by project by but at once and nationally-wide. An important driver of the BIM globalization regarding open standards is the government, that has the power to avoid the situation of having several standards, created by the industry, by for instance funding the development and establishment of open standards methods, processes and data structures. This report focuses on government BIM policies around the world and on the extend of which different countries have applied open standards. 1.2. Open data standards Every standard is based on 3 main compounds – Terminology, Process and Digital storage. Based on that the open BIM standards are developed as seen on Figure 1. BuildingSMART Alliance is the international driver of open standards and has been in charge of guiding software vendors like Archicad, Grafpisoft and others, what standards should be developed in order to allow a free and open exchange of structured information and to improve interoperability and quality of the data. There is a wide range of industry standards and file formats available for exchanging and managing BIM data. Figure 1 Specifications summary (Source: BuildingSMART) Chair of Computational Modeling and Simulation Seite 3 Chair of Architectural Informatics Advanced Topics in Building Information Modeling Process Standard – Information Delivery Manual (IDM) BuildingSMART Information Delivery Manual integrates business processes and simultaneously provides detailed specification information that is required in order for these processes to be carried out. Standards for IDM can be found in ISO 29481-1.2016, where the interoperability between software applications is described and a basis for the accurate high-quality information exchange is provided. Another standard is ISO 29481-2:2012, which explains the needed methodology and format for describing the acts between participants in the building project. Data Standard – Industry Foundation Class (IFC) IFC was developed as a neutral data format to describe, exchange and share information specifically used in the building and facility management sector and between different proprietary software applications. IFC has been the key to data interoperability in contrast to native data, which is a proprietary software standard from the authoring tool of a BIM model. A detailed description is provided in ISO 16739. Change Coordination – BIM Collaboration Format (BCF) BCF is a ‘simplified’ open standard XML schema that encodes messages to enable workflow communication between different software tools. IFC contains GUID’s linked to the objects and therefore is not suited for documenting issues or workflows. BCF, on the other hand, separates the communication, in form from textual comments or screenshots between coordination parties, from the actual model. Mapping of Terms – International Framework for Dictionaries (IFD) The data dictionary is one of the main components of a standard that enables a flexible method of linking existing databases with construction information to a BIM model. It is a library, based on IFD standard ISO 12006-3:2007, that specifies the language-independent information in a model. Used to store and provide a reference between classification systems, information models, object models and to prove models within a common framework. Different countries agree on how to handle classification on their own. The Netherlands, for example, use a comprehensive terminology - LexCon data and other countries have an increased interest in IFD standard and are working to clarify how to handle data classification. Process Translation – Model View Definition (MVD) MDVs provide subsets of the IFC data model that are in particular needed to support the specific data exchange requirements during the life-cycle of a construction project. An MVD provides implementation guidance for all IFC concepts, such as classes, attributes, relationships, quantity definitions, used in a subset. Chair of Computational Modeling and Simulation Seite 4 Chair of Architectural Informatics Advanced Topics in Building Information Modeling Figure 2 IFD Library - a mapping mechanism (Source: BuildingSMART) 1.3. Construction Operations Building information exchange COBie COBie is another non-proprietary data standard, delivered in a spreadsheet data format, and contains a ‘subset’ of information for a FM handover (all except graphical data), so as a specification for all of the spaces and equipment in a building. Originally developed by the US Army Engineering Corps to reduce or eliminate the cost of construction handover documentation and improve of the quality of that information so that it can be used effectively by the facility manager, today COBie is part of UK Government’s BIM Level-2 mandate. The bases of COBie methodology have been explained in the IFC/COBie report from 2012 by the National BIM Library of UK. The findings of the report are very straight forward: in order to reproduce an electronic version of the current paper handover documents, 3 type of information would be needed: facility maintenance, operations and assets. In other words: what assets the owner wants to maintain, how is the information going to be consumed and at what level of detail. COBie structure The contended of a COBie file includes a vertical and a horizontal decomposition of the building, information about facility, floor, space and zones, so as the equipment installed in the building. COBie responsibility matrix allows project member to identify responsibilities for specific elements within a data set, demonstrates the mapping between IFC and spreadsheets versions of COBie data and identifies the IFC filtering list, for the people using IFC coordination view. Whether you use the STEP format, the IFC XML, spreadsheet Chair of Computational Modeling and Simulation Seite 5 Chair of Architectural Informatics Advanced Topics in Building Information Modeling XML or COBie light specification, the standard data model developed to express what COBie information is required is contained in the IFC COBie model view definition. Figure 3 The “Type” worksheet within a typical COBie spreadsheet (Source: NBS) BuildingSMART Specification for a model view definition COBie is part of National BIM Standard Version 2 published in March 2012 by the US. An important aspect is the specification of the way that information can be transferred between the spreadsheet version and the IFC version of COBie. Since its initial publication in March 2012 some additional changes have been included in the current version of COBie – Version 2.4. For the initial specification of the FM handover version the BuildingSMART has developed an important tool called ifcDoc Tool to establish consistent view model definitions. This COBie model view identifies all the objects necessary to support COBie and the relationship between them. It also explains how the objects correspond to elements in real buildings and provides all the class diagrams necessary to understand all the relationships between entities in the model definition. BuildingSMART has e specification to map a model view definition into a spreadsheet for COBie found in the COBie responsibility matrix. It explains how to map between IFC and COBie, so as the IFC entities and objects are filtered out and not be included in the COBie data. Several different products to transform