New Dimensions in Design
3-D Building Information Modeling offers more than a better visual
- By George Crawford
- Dec 03, 2007
Facility designers traditionally
have used two-dimensional
(2-D) drawings to
illustrate plans, sections, and
associated information to
their clients.
This format requires reviewers to have strong
visualization skills. It often lacks sufficient detail
in the early stages, giving reviewers little to comment
on until the drawings are nearly complete.
By that time, changes are costly and time-consuming.
Two-dimensional drawings also fall
short in properly communicating compact technologies,
such as membrane bioreactors
(MBRs), which can increase design complexity
and the potential for interferences.
When three-dimensional (3-D) modeling
initially was applied to projects, facility designers
used it to visualize concept layouts and
structures and agree on an overall plant layout.
Following an agreement, designers completed
the work using the two-dimensional drawing
approach.
National BIM Standard
Definition Of BIM—
buildingSMART A Building Information Model (BIM) is a digital
representation of physical and functional characteristics
of a facility. As such, it serves as a
shared knowledge resource for information
about a facility forming a reliable basis for decisions
during its lifecycle from inception onward.
A basic premise of BIM is collaboration by
different stakeholders at different phases of the
lifecycle of a facility to insert, extract, update, or
modify information in the BIM process to support
and reflect the roles of that stakeholder.
The BIM is a shared digital representation
founded on open standards for interoperability.
The National BIM Standard is part of the
global buildingSMART Information Delivery
Manual Initiative. |
Enter BIM 3-D
Still another dimension was needed, and the
Building Information Model (BIM) 3-D has
now provided that. This newer design tool captures
facility information from smart 2-D
drawings, three-dimensional models (3-D),
and other information (typically manually
entered data).
BIM 3-D is a major step forward, because
it integrates multidiscipline design, visualization
and drawing production, yet still allows
designers to extract 2-D plans and sections for
contract purposes.
Other benefits include:
n favorable design costs;
n simplified identification of conflicts and
interferences among piping, structures, and
equipment (from process mechanical, HVAC,
structural, architectural, and electrical); and
n assurance that the final drawings are
coordinated without conflicts or superseded
information.
Taking a virtual “walkthrough” of a proposed
water or wastewater facility helps designers,
owners, plant staff, regulatory agencies, or
contractors clearly see the layout and function
of the various aspects of the facility. Once the
model is complete, construction drawings can
be extracted in a 2-D format for contractors,
who, if they so desire, also can review the 3-
D version to better understand certain aspects.
BIM includes 3-D modeling but emphasizes
collaboration and provides additional information
to deliver a more comprehensive facility.
Intelligent drawings
When instrumentation and control designers
use Intelligent Process and Instrumentation
Drawings, information can be integrated with
BIM and manual data. The model enables the
use of interference
detection software and
has the ability to generate
fully dimensioned
isometric drawings
of piping with bills
of materials/material
take-offs for mechanical
components. It also allows quantity takeoffs
of building components. Nondesign information,
such as cost calculations, energy
simulations, or building code checking, can be
incorporated. The model can provide the
instant renderings and photorealistic images
common to 3-D visualization models but with
specific design details shown rather than an
artist’s rendering.
CH2M HILL, a full-service engineering,
construction, and operations firm, has been
using BIM 3-D to deliver civil, water, wastewater,
industrial, and building projects since
the late 1980s. Recognizing great benefits for
clients and project design, the firm developed
a standard approach to delivering BIM. Routine
use of this process has increased design efficiency,
created a library of models that can be
adapted to future needs and, on each project,
created renderings and images that facilitate
and enhance client and regulatory review,
because they promote faster understanding.
Water reclamation facility
In a recent project, a CH2M HILL design
team used BIM 3-D to solve a visualization
problem in Henderson, Nev.
Henderson, a Las Vegas suburb, has experienced
rapid growth over the last 10 years. That
growth has meant that current capacity was
lacking in the interceptor sewers conveying
wastewater from West Henderson to the main
water reclamation facility. In addition, reclaimed
water from the facility needed to be pumped
back to West Henderson, requiring significant
power. The city opted to build a satellite water
reclamation facility in West Henderson to save
about $5 million in projected annual costs.
Summary of BIM
Features and Benefits
BIM creates the capability to retrieve intelligent
data and facility images throughout the project’s
lifespan, providing significant value and
return on investment.
Project stakeholders achieve greater understanding
through 3-D virtual “walkthroughs” of
the new facility, at all stages of the design
process, leading to earlier and higher quality
decisions.
Improved design quality (interference
checking, extracted drawings), combined with
the inclusion of all design disciplines, decreases
the risk of error and cost overruns.
Questions during construction can be
answered by viewing the model with the construction
contractor. This helps to explain
design details that may not be understandable
or shown in 2-D drawings.
Designs and costs are optimized, including
the use of simulation and analysis tools.
BIM accommodates a variety of traditional
and alternative delivery approaches.
Capital cost estimates can be made by
extracting quantities from the project database
and applying local or national cost multipliers.
Quantities are categorized by the data housed
within the model, so the database knows what
material a building component is, or what
material and flow stream is associated with a
pipe. The effort to produce capital costs have
been reduced more than 30 percent because of
the availability of the project database. |
The Southwest Water Reclamation Facility
is designed to remove wastewater from the
collection system and to supply water into the
reclaimed water distribution system. The
design team completed the facility planning,
predesign, and final design for an 8-milliongallon-
per-day (mgd) average daily flow facility
and potential expansion to 16 mgd using
MBR technology.
The facility design began with 3-D modeling
during the schematic phase. The team
created models for each facility, providing an
integrated approach. Each discipline worked
within the facility-specific models to develop
key parts of the design. The team located major
piping, ductwork, electrical “right of ways,”
structures, and equipment within the models,
creating an overall model reflective of the sizing
and facility layouts. Utility Services Department
engineers and operators viewed that
model for the schematic design review to finalize
key decisions.
The team further developed the facility
models, all in 3-D, during the remaining
design phases. At planned milestones, traditional
2-D drawings were extracted and submitted
to the client. Then, the team held
detailed design reviews for each 3-D facility
model, working through the facilities with
the client from a flow-path perspective. The
team also provided renderings within the
design drawing sets to help reviewers visualize
the facilities.
By integrating each facility model and the
site work into a common model using InRoads
software, the overall model was animated to
show a 360-degree flyover of the facility.
The ability to perform design reviews while
working through the 3-D models allowed a significant
change in the review process. Instead
of having to search through 500 multidisciplinary
drawings, the client was able to view all
disciplines in the live model reviews, providing
a valuable interactive approach to the design
process and client input to key decisions.
The use of 3-D and BIM is now CH2M
HILL’s most efficient method of project delivery.
The actual evolution of the design models
allows each discipline to work together in
the same model, enhancing coordination and
limiting the potential for rework. As the library
of projects grows, base models become available
for specific unit processes that can be considered
“templates” for future designs. This
approach now is being used for water and
wastewater treatment plant design projects in
all parts of the world.
3-D/2-D or BIM 3-D—
What’s the Difference?
3-D/2-D
• Designers create 3-D visualizations of the
plant layout concept
• Once the layout is agreed upon, 3-D work
stops
• The design is completed in 2-D
BIM 3-D
• Designers create 3-D visualizations of the
plant layout concept
• Once the layout is agreed upon, multidisciplinary
design is completed within an integrated
3-D model
• 2-D plans and sections are extracted from
the 3-D model for contract drawings
• Accurate and comprehensive representation
of information
• Model components linked to information
databases
• Useful across project lifespan |
This article originally appeared in the 12/01/2007 issue of Environmental Protection.
About the Author
George Crawford is a recognized expert in membrane bioreactor (MBR) analysis, process, design, and equipment system procurement as well as conventional wastewater process analysis and design. He has 30 years experience as a technology specialist and project manager with CH2M HILL and has been involved in the design of 20 MBRs, nationally and internationally. Crawford received a master of science degree in civil/environmental engineering from the University of Toronto. He currently lives in Toronto, Canada. He can be reached at (416) 499-0090 ext. 201.