| In its initial public demonstration, the
world's first seismic testing apparatus for
nonstructural components performed exactly as designed
last Friday at the University at Buffalo and MCEER,
providing engineers with the first realistic,
experimental method of simulating and evaluating how
earthquakes damage building equipment, contents and
components.
The National Science Foundation-funded Nonstructural
Components Simulator (NCS) realistically simulated a
fully equipped, upper-story hospital room experiencing
two levels of seismic activity.
The demonstration took place in the Structural
Engineering and Earthquake Simulation Laboratory (SEESL)in
UB's School of Engineering and Applied Sciences for an
audience of more than 100 earthquake engineers and
industry representatives from across the U.S. who were
attending the UB/MCEER symposium on "Seismic Regulations
and Challenges for Protecting Building Equipment,
Components and Operations."
"We are very pleased with the performance of the
Nonstructural Components Simulator," said Gilberto
Mosqueda, Ph.D., assistant professor of civil,
structural and environmental engineering in the UB
School of Engineering and Applied Sciences and lead
designer and builder of the facility with Rodrigo
Retamales, a doctoral student in the same department.
"These experiments clearly demonstrate new
capabilities available at UB to test many types of
nonstructural systems, whether they are attached to
walls or connected between the top and bottom of a story
in a building," he said. "We look forward to assisting
our industry partners in testing and improving the
performance of their products during earthquakes."
The NCS is the only system in the world capable of
realistically simulating how the contents and
distributed systems (i.e., water, sprinkler, medical gas
piping) in important buildings, such as hospitals, react
to strong ground shaking and amplified floor motions,
said Mosqueda.
Mitigation and response to extreme events, whether
natural events like earthquakes and hurricanes, or
manmade like terrorist attacks, is a research strategic
strength identified in the UB 2020 strategic plan being
implemented by the university with the goal of rising
among the ranks of the nation's public research
universities.
Last week's tests were representative of a "design
basis" earthquake, which has a 10 percent probability of
occurring within the next 50 years and a "maximum
considered earthquake," the largest earthquake shaking
that a building could experience in its service life in
a high-seismic zone in the U.S.
UB engineers and SEESL technicians constructed and
equipped a 10-foot by 12-foot composite hospital room,
outfitted with numerous systems typical of a
critical-care facility, ranging from mechanical systems,
such as sprinklers and medical gas lines, to
ceiling-mounted surgical lamps, a suspended ceiling,
infusion pumps and wall-mounted computer monitors.
"Ben," a crash dummy provided by Calspan, Inc., of
Buffalo, was seated on top of a gurney that had been
secured in its stationary position. Nonetheless, the
gurney was tossed about like a toy in both tests, while
"Ben" -- 180 pounds of dead weight -- hit the floor in
the maximum event and was very severely tossed about in
the design basis quake.
During the design basis earthquake test, UB engineers
were surprised to see wall-mounted EKG monitors fall
from their pedestals, since they were mounted according
to current California standards. The maximum considered
earthquake test caused a few ceiling tiles to fall.
"These failures highlight some potential
vulnerabilities that should be further studied," said
Andre Filiatrault, Ph.D., professor of civil, structural
and environmental engineering at UB and director of
SEESL.
While he cautioned that general conclusions cannot be
drawn from these tests, which were conducted primarily
to demonstrate the capabilities of the NCS, nonetheless,
he said that these unexpected failures point to areas
where engineers and manufacturers may want to focus
their joint efforts in the future.
The NCS is coming online just as a consortium of
universities, led by the University of Nevada at Reno,
and including UB, has been awarded a five-year, $3.6
million National Science Foundation NEES Grand Challenge
grant to investigate the performance of nonstructural
systems during earthquakes.
For its portion of the research, UB's Department of
Civil, Structural and Environmental Engineering will
receive approximately $700,000.
In addition to complementary facilities at UNR, UB's
Nonstructural Components Simulator and versatile, twin
movable shake tables will provide a test bed for these
research studies to conduct experiments to better
understand and improve the seismic performance of
nonstructural systems, particularly ceilings, piping and
partition walls.
In addition to Filiatrault, Andre Reinhorn, Ph.D.,
Clifford C. Furnas Professor of Structural Engineering
at UB and former SEESL director, and Andrew Whittaker,
Ph.D., professor of civil, structural and environmental
engineering will be leading the UB studies.
The testing platforms of the NCS were designed and
constructed by UB engineers and SEESL staff; the
hydraulic actuators that drive the system were
manufactured by MTS Systems Corporation.
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