|
Advertising supplement provided by
American Institute of Steel Construction
By Larry Flynn
Lanny Flynn, P.E., a structural engineer with Magnusson Klemencic,
Seattle, uses this method to drive his use of BIM to
deliver a client the tangible benefits of a faster schedule
at a lower cost. While with the Tacoma, Wash., structural
engineering firm of Putnam, Collins, Scott Associates (PCSA),
Flynn helped promulgate the delivery of the steel for construction
of Tacomas Mt. Tahoma High School upstream to the design
phase. This shortened the construction schedule of the 279,000square
foot high school by three months.
A firm cannot implement BIM by acting alone. There must be
a commitment from at least some other key members of the building
team to make integration of at least part of the project possible.
In the case of Mt. Tahoma High School, PCSA, which detailed
the project in-house, exported the model to steel fabricator
Allied Steel, Lewistown, Mont.
Alliances should be formed with design consultants and contractors
who have some experience working with BIM or who are eager
and committed to beginning the process. A complex project
such as GMs engine plant required a total commitment
on the part of the entire building team to make the project
a reality in BIM and bring about the productivity gains sought
by the owner. Ghafari Associates, the projects A/E firm,
teamed with firms it had worked with previously on another
GM BIM project, including fabricator Douglas Steel, which
has been modeling in 3-D since 1995, and mechanical contractor
John E. Green Co., Highland Park, Mich. The design and construction
team not only collaborated via the exchange of the 3-D model,
the team co-located together in one office, facilitating communication
to an even greater extent.
As the GM project demonstrates, the focus of BIM is to increase
project productivity in design and construction by designing
and virtually constructing a project before the project is
built in the field. The transition to BIM is a cultural change
that requires a rethinking of the building design and construction
industry process. There are hurdles to bringing about such
significant changes with BIM, which may generate initial resistance,
and must be overcome through clear and open communication
with the owner and other members of the building team.
BIM requires some reallocation of:
|
Defining BIM: A Process and
a Tool
|
| A Building Information Model is
a fully coordinated and detailed 3-D equivalent
of traditional construction documents, created in
the broader process of Building Information Modeling.
This process encompasses the entire project from
design through construction completion, and then
becomes a long-term asset in managing the life cycle
costs of the structure.
Although there are many variations, Building
Information Modeling is defined as a process for
creating, communicating, and reviewing building
information in a collaborative manner.
Experts emphasize that it is the BIM process
that is the most important issue on which to focus
for architects and other building team members.
BIM is a fully integrated design and construction
process that uses 3-D modeling techniques and
technology to lower costs and compress schedules.
It is not a software application that is purchased
off a shelf. BIM is about changing the culture
of the building design and construction industry;
not simply using a different set of tools to conduct
the same building process as usual.
There are different levels and layers of BIM,
which can be used to integrate all or part of
the building team and project. When viewed horizontally
through the eyes of the designer, BIM technology
can be used to integrate the architect, structural
engineer, other consultants and specialty contractors
in the design process to create a comprehensive
3-D model of the project. While highly beneficial
to the design process, a horizontal view of BIM
fails to take advantage of the full opportunity
BIM offers to a project.
BIM can be employed vertically on a trade-by-trade
basis to integrate a segment of the project, such
as fabrication and delivery of the structural
steel package, into the construction process.
This is a process which is being applied with
great success on many projects across the U.S.,
where information is being directly transferred
between design, detailing and fabrication software
and processes. The end result is the enhanced
productivity that occurs through quality-controlled,
interference-checked, close-tolerance offsite
fabrication, reducing onsite labor and time. The
future of building construction does not rest
in onsite activities, but labor-saving, cost-controlled
offsite fabrication.
Some architects conceive of BIM as a spatial
repository of data for a structure, housing data
on furnishings and equipment. A mature BIM includes
the skeletal and spatial characteristics of a
structure. It is the integration of all pertinent
information relative to the design, construction,
operation, and maintenance of a structure that
generates the long-term savings identified in
the 2004 National Institute of Standards and Technology
(NIST) study titled Cost Analysis Inadequate Interoperability
in the U.S. Capital Facilities Industry, which
is summarized in Interoperability and the Construction
Process, a free document published by AISC (www.aisc.org/interoperability).
The NIST study identified that the lack of adequate
interoperability (which would be accomplished
through the implementation of BIM) increased operations
and maintenance by 23 cents a square foot over
the life cycle of the facility. The ultimate value
to a project owner comes through full horizontal
(design) and vertical (construction) integration
of the project, both during construction and in
the maintenance and future modifications to the
structure.
The Building Information
Model can be defined as:
- A complete 3-D digital representation of a
building system or subsystem. It includes exact
locations and accurate sizes of the various
components that make up the building system.
A BIM is a replacement for the more traditional
set of construction documents.
- All major building systems will typically
be represented by their own BIM and are typically
created by their own consultant or team that
has been assigned to design that system. Structural,
MEP, elevator, exterior wall, and foundation
are typical building systems that are represented
by a BIM. The BIM is coordinated with the project
dimensional BIM and is the deliverable from
the consultant or team that has been contracted
to provide design services.
- An integrated BIM includes other BIMs. This
is comparable to a complete set of traditional
project documents that includes the architectural,
structural, MEP, and foundation documents.
- In most cases, the term, construction
documents can be replaced with BIM to
understand the concept as it relates to building
construction.
- A BIM typically has the feature to easily
extract information in visual or document form
to enable use by various project stakeholders.
- Most BIMs are used directly for the production,
manufacturing or fabrication of the system components
to be assembled into the final constructed building.
|
|
|