|
 |
VIDEO:
Quicktime video with UC Berkeley civil engineering assistant
professor Khalid Mosalam describing the December 12
test.
|
| |
Over
the years, thousands of woodframe, multi-unit residential
buildings have been constructed with tuck-under parking
at the ground level, which can create a soft story configuration
that may lead to severe damage and even collapse under
strong earthquake shaking. Buildings like this have
collapsed in recent earthquakes. Shown here is a view
of a full-scale apartment bulding model (prior to installation
of stucco on exterior and gypsum board on interior)
that has been seismically retrofitted for testing on
December 12.
|
| |
A
new steel frame, designed to resist seismic forces,
has been installed to simulate the typical way buildings
like this have been retrofitted. Such retrofits typically
include steel beam supports like these.
|
December
12 shake test on the nation's largest earthquake simulator
of a three-story woodframe apartment building
BERKELEY
— On December 12, engineers will conduct a seismic
shake test of a full-scale three-story woodframe apartment
building on the nation's largest earthquake simulator. The
experiment, by University of California, Berkeley, engineers,
will be the largest of its kind done to date in the country,
and will subject the structure to multi-directional ground
motions equivalent to that recorded during the 1994 Northridge
earthquake.
Over the
years, thousands of woodframe, multi-unit residential buildings
have been constructed with tuck-under parking at the ground
level, which can create a soft story configuration that may
lead to severe damage and even collapse under strong earthquake
shaking. Buildings like this have collapsed in recent earthquakes.
Several
buildings of this structural type, typically constructed in
the 1960s or 1970s, experienced ground story collapse in the
1989 Loma Prieta earthquake and in the 1994 Northridge, California
earthquakes, including the Northridge Meadows apartment complex
where 16 people died.
Since then,
a number of these structures have been seismically retrofitted.
Typical retrofits include the addition of a steel frame around
the garage openings, the installation of shear walls, and
attaching such buildings to their foundations.
No large
scale experimentation has been conducted to verify the effectiveness
of these retrofit measures. On December 12, a team lead by
Khalid Mosalam, assistant professor of civil engineering,
and Stephen Mahin, professor of civil engineering, will conduct
a shake test to see how these retrofit measures actually peform.
BACKGROUND:
The full-scale
building is outfitted with wall finish materials, a white
stucco exterior, windows and doors. The tuck-under parking
is retrofitted with a steel frame.
The experiment
is part of a larger $6.9 million woodframe project funded
by the Federal Emergency Management Agency through the California
Office of Emergency Services after the Northridge earthquake.
The UC
Berkeley test will also be an early demonstration of the efficacy
of using tiny, wireless remote sensors to provide feedback
on the structural integrity of the building.
The Consortium
of Universities for Research in Earthquake Engineering (CUREE)
manages the project under subcontract to the California Institute
of Technology. Results from the UC Berkeley test will be used
to evaluate the effectiveness of current building ordinances,
as well as to develop improved codes and standards.
ATTENTION MEDIA:
For further information, contact Sarah Yang at (510) 643-7741 or scy@pa.urel.berkeley.edu.
|
