It's an exciting
time to be involved in construction and building technology,
says James T. Garret, a civil and environmental engineering
professor and lab director at Carnegie Mellon University in
Pittsburgh. He says there is a huge need for instrumentation
and monitoring of infrastructure to better build, manage,
protect and maintain it. "A $30,000 BMW has more sensors
and monitors on it than a $10-million bridge," he notes.
Linking technology, such as vortex modeling and construction,
yields insight. (Graphics courtesy of Flow Analysis Inc.)
Yet the potential of technology
only starts to be realized when people perceive possibilities
and systematically examine them. That's the nature of research.
Stumbling blocks often appear
on the long path ideas follow from concept, to prototype,
to trial product, to the ultimate status of acceptance as
a useful tool. But the one thing surviving ideas have in common
is that they are championed by believers and are conveyed
from mind to mind.
Backtracking the history of a
tool being tested by New York City-based engineering firm
Weidlinger Associates Inc. gives a good example of research
evolution. The firm specializes in blast analysis, retrofits
and blast hardening, as well as structural engineering. Weidlinger
currently is testing software that began life a dozen years
ago as research for the U.S. Army to study helicopter rotors.
It models whirlwinds.
Research into wireless networks at Carnegie Mellon starts
with low-tech, push-in model and plan. (Photo by Tom Sawyer
"The vortex from one blade
directly affects the other blades," explains Frank Marconi,
whose job is "applied science" at Weidlinger. He
says the thumping noise helicopters make is the sound of blades
slicing through vortices. He thinks the vortex modeling software
can be applied to the construction industry.
The tool uses an approach called
vorticity confinement to study the swirls that shed from objects
as wind passes. As anyone who has watched a wind devil or
tornado knows, they can endure for a long time. They are also
what makes clouds of smoke roil and define the dispersion
of pollutants in the sky. The software can model that as well.
Vorticity confinement is just
beginning to be marketed by a start-up company, Flow Analysis,
Tullahoma, Tenn. Marconi is the person at Weidlinger whose
mind is currently cradling the vorticity confinement idea.
Weidlinger is testing the software
on a cable-stayed bridge project. The software's predictions
are being compared to wind-tunnel analysis of alternative
designs for fairings on new deck edges for the Bronx-Whitestone
Bridge in New York City. The engineers need to understand
how the designs affect the wind as it parts around the edge
of the deck and sheds vortices downstream. The swirling air
could affect deck oscillation and vehicles on the roadway.
Marconi says the software can
predict turbulence generated by wind rushing past buildings
and, because it works quickly, could be the basis for real-time
emergency response to airborne contamination plumes. Weidlinger
has used it to craft a proposal for a system to monitor urban
landscapes and subway systems and to predict contamination
paths of released biochemical agents. Such predictions could
inform evacuations and advise strategies to contain and limit
damage. "It could be used to compute how chemical agents
will propagate in a building," Marconi says.
The right software can make the difference between toys
and tools. (Photo by Tom Sawyer for ENR)
Before Marconi got hold of it, the only previous commercial
application of the software had been to generate boiling clouds
of computer-generated smoke for a few movies, including The
Mummy. The movie industry learned of it at a computer trade
show. John Steinhoff, the professor who developed the tool
at the University of Tennessee Space Institute, Tullahoma,
was demonstrating it to gauge commercial interest.
"It's a perfect example of
something that has been tested against experience in a slightly
different field," Steinhoff says. "Now we're trying
to transfer the technology to the architectural and engineering
University researchers often build
new tools to answer questions posed by industry and government.
Both provide funding and support through grants and contracts.
A look at just some of the projects under way at Carnegie
Mellon offers a good example of the breadth of scientific
inquiry across the U.S. today.
Researchers at the university's
Advanced Infrastructure Systems Lab in the Institute of Complex
Systems are trying to improve information technology in infrastructure
construction and operation. They are blurring the lines between
departments, such as civil engineering and computer science,
to cross-pollinate ideas. "I see information technology
as a stimulus for inter-disciplinary research," says
John Anderson, dean of the college of engineering.
Improving software for use with
wearable computers to take design data in the field is one
area. "We always say it's a toy when you buy it, but
by developing the right software for it, it becomes a tool,"
says researcher Christian Buergy.
Others are developing microsensors
to embed in concrete and other materials that can detect changes
in electromagnetic or chemical characteristics and infer levels
of deterioration and corrosion. Some of this research builds
on technology from the medical sciences, including magnetic
WARRIORS Hearty motors and gear-trains are the
costly parts. (Photo by Tom Sawyer of ENR)
Another area of study at Carnegie Mellon with crossover potential
is remote sensing using miniature robots. The idea driving
the work, undertaken for the U.S. Marine Corps, is to create
a series of "mini-bots" that can self-navigate and
scurry through ventilation ducts or other confined spaces.
They use lasers, video, thermal or acoustic sensors to navigate,
peer through vents and map layouts to locate hostile characters
and dangers, reporting back wirelessly to their operators.
The goal is to make them small,
robust and cheap, and to endow them with a variety of modular
sensors that can be snapped onto a common frame. They are
designed to work in concert. Some versions assemble themselves
end to end and climb over obstructions or stairs, then scatter
again to reconnoiter. There is even a repair-bot in development
that can find a damaged or trapped fellow and, using a built
in fork-lift, free it or remove defective modules and replace
them on the spot. "Once small robots catch on, there
will be many places they could be used that nobody has ever
thought of," says researcher Robert Grabowski.
Other researchers are testing
laser scan monitoring of ongoing steel erection for early
defect detection. Others are searching for ways to improve
jobsite information flow. The work ranges from creating daily
reporting systems to experimenting with wireless data networks.
They want to better understand the weaknesses and strengths
of such networks with an eye toward using them on construction
sites. Chips on tools, people and equipment could use networks
to automatically report real-time status of activity all over
the site, opening up many new possibilities for productivity
enhancement and quality control.
RESULTS Polytechnic researchers develop sequencing
tools for complex work. (Graphics top left courtesy of
Brooklyn Poly-technical University; Photo by Tom Sawyer
"There is a tremendous amount
of technology we don't have to develop ourselves, but there
is a lot of research needed on what is the most appropriate
use," says Carnegie Mellon civil and environmental engineering
professor James Garret, who directs the labs. "You have
to really understand the problem that is being encountered
in the field."
The picture at Carnegie Mellon
is repeated at many other institutions. Researchers at Arizona
State University's Del E. Webb School of Construction are
studying cemented soils, green building, and the use of geographic
information systems and satellite positioning technology to
coordinate activities on complex, multiple-site construction
projects, such as super housing-tract developments.
In most cases, research is conducted
in partnership with government or industry. At Brooklyn, N.Y.'s
Polytechnic University, which has a graduate-level program
in construction engineering and management, one research partner
is the agency that builds and manages New York City's subways.
A current project is to develop
3D and 4D models of a planned elevated subway platform renovation
in a severely constrained, high-traffic site. Sequencing alternating
phases of demolition and construction while keeping the station
in use is a typical problem with subway renovations, although
in this case it is exacerbated by the need to keep streets
and sidewalks below unencumbered as well. Researchers expect
to transfer technology directly to the Metropolitan Transit
Authority for replication on future projects.
LAB NIST project pushes job quality control boundaries
to achieve high standards for re-search. (Photo by Tom
Sawyer for ENR
Another research project pursued
at Polytechnic by Eric Hsiao-Hua Chang, takes the 4D sequence
scheduling problem even further by bringing multiple sequences
into a single model. He calls his patented approach NDCON,
for n-dimensional construction management information system.
The goal is to provide a tool to help contractors adjust and
re-balance complex schedules when the effects of delays ripple
through other disciplines. Polytechnic has often found itself
at the applied end of the research spectrum, as it is construction
manager of the school's own multi-project, $95- million construction
But one of the most striking examples
of putting your construction where your research is has to
be a project to construct a new Advanced Measurement Laboratory
at the National Institute of Standards and Technology in Gaithersburg,
Md. Every aspect of the $235-million project is infused with
the proceeds of research, from the distributed and collaborative
design activities and project management, to the design features,
quality control measures and construction techniques used
to build the structures.
The facility is a cluster of linked
buildings, more than half a million sq ft in total. It includes
a clean room, two highly controlled instrument labs and two
metrology labs buried underground to shelter them from vibrations
and temperature changes. In one, temperatures will be held
to a tolerance of +/-0.01°C. That is quality control.