2 BUILDING INFORMATION
MODELING
BIM is the process of generating, storing, managing,
exchanging and sharing building information in an
interoperable and reusable way. A BIM system is a
tool that enables users to integrate and reuse the
information of a building and the domain knowledge
throughout the lifecycle of a building (Lee, 2006). A
BIM system is a central system that manages various
types of information, such as enterprise resource
planning, resource analysis packages, technical
reports, meeting reports, etc. However, the main
feature of a BIM is the 3D modeling system with
data management, data sharing and data exchange
during the lifecycle of the building. As a matter of
fact, a building is composed of geometrical elements
which are the basis of a building’s design.
Furthermore, parametric modeling provides
powerful mechanisms that can automate the
generation of the building information. Especially
those mechanisms, in conjunction with the behavior
of building object and an object-based system,
facilitate the maintenance and the validity of the
building’s designs. Several definitions of BIM can
be found in the specialized literature. The NBIMS
(NBIMS, 2007a) divides BIM categories in three
axes which are Product, Collaborative Process and
Facility. The Product is an intelligent digital
representation of the building. The Collaborative
Process covers business drivers, automated process
capabilities and open information standards used for
information sustainability and fidelity. The Facility
concerns the well understood information
exchanges, workflows, and procedures which are
used by the different teams as a repeatable,
verifiable and sustainable information-based
environment throughout the building’s lifecycle.
According to (NBIMS, 2007b) a BIM is a
computable representation of all the physical and
functional characteristics of a building and it is
related to the project information, which is intended
to be a repository of information for the building
owner/operator to use and maintain throughout the
lifecycle of the building. According to Autodesk
(Autodesk, 2002), BIMs have three main features:
They create and operate on digital databases for
collaboration. They manage change through those
databases so that a change to any part of the
database is coordinated in all other parts. They
capture and preserve information for reuse by adding
industry-specific applications.
By analyzing the BIM definition we index a set of
features common to BIM systems (Tolman, 1999) ,
(NIST, 2007), (Eastman, 2005), (Zamanian, 1999),
(Sable, 2005), (Cruz, 2006). (1) The main feature of
BIM is the ability to store, share and exchange data.
Many methods are used to realize those processes
like files or databases. Concerning data exchange,
BIMs are developed with the aim to keep open non-
proprietary data format exchange. (2) Data managed
in BIM processes concerns building geometries
which are most of the time 3D data. 3D data is more
helpful for designers for the visualization of
complex construction conditions than 2D while it
communicates at the same time design intentions.
AEC industry visualizes the design using
stereoscopic projection tools to create an immersive
experience (Dace, 2007). Spatial relationships
between building elements are managed in a
hierarchical manner. (3) BIMS are data rich and
comprehensive as they cover all physical and
functional characteristics of a building. BIMs are
also rich semantically as they store a high amount of
semantic information about building elements.
Moreover, the data model is fully object oriented to
facilitate data management and process definition.
(4) Some of the BIMs are extensible to cover
unimplemented information domains. For instance,
the development of IFC 2.X went through a major
change in order to extend progressively the range
and the capability of IFCs by using modules. (5)
BIMs play a central role in the building lifecycle. In
order to ease data exchange, a data format has to be
widely used. By definition, BIMs enable
interoperability among diverse applications using a
shared universal information standard. (6) The
lifecycle of the project in AEC is composed of
several phases which have to be validated by the
corresponding AEC engineering designer. BIMs
cover several lifecycle phases. The state of these
phases is processed by BIMs in order to sequence
and schedule the process. BIMs support 4D analysis,
where activities from the project schedule can be
simulated and studied to optimize the sequence of
construction.
Our research aims at solving the problem linked
to the constant IFC evolution (4). The definition of a
complete framework that allows the management of
the knowledge around the building process requires
an extensible and generic formalism to represent
both specific data describing building information
and connected information defined by the user
during the building’s lifecycle. It requires also tools
to handle and query the corresponding modelling
data, and it requires also tools to manage the data
evolution during the building’s lifecycle. Moreover,
the contextual management of data that needs to
WEBIST 2010 - 6th International Conference on Web Information Systems and Technologies
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