Transcript Document

George E. Brown, Jr.
Network for Earthquake
Engineering Simulation
Field Testing & Monitoring
of Structural Performance
John W. Wallace
Joel P. Conte
Deborah Estrin
Patrick J. Fox
Jonathan P. Stewart
Daniel Whang
University of California, Los Angeles
7 NCEE
July 21-24, 2002
Acknowledgements
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Funding provided through a cooperative agreement with the
National Science Foundation George E. Brown, Jr. Network
for Earthquake Engineering Simulation (NEES)
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Dr. Priscilla P. Nelson, Director
Division of Civil and Mechanical Systems
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Joy Pauschke, Ph.D., P.E., NEES Program Director
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Thomas L. Anderson, Ph.D.
NEES Equipment Project Coordinator
UCLA NEES Personnel
John W. Wallace (PI)
PhD, UC Berkeley, 1989
Structural
Daniel Whang (Project Manager)
PhD, UCLA, 2001
Geotechnical
Joel P. Conte (co-PI)
PhD, UC Berkeley, 1990
Structural
Eunjong Yu
(Graduate Student Researcher)
Jonathan Stewart (co-PI)
PhD, UC Berkeley, 1996
Geotechnical
William Elmer
(Engineering Aide)
Patrick J. Fox (co-PI)
PhD, University of WisconsinMadison 1992, Geotechnical
Colin Means
(Engineering Aide)
Deborah Estrin (co-PI)
PhD, MIT, 1985
Computer Science
Balaji Vasu (Webmaster)
Project Overview
Wireless
Equipment Overview
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State-of-the-art data
acquisition system w/
wireless capabilities
Networking equipment to
enable near real-time
field connectivity to
NEESgrid
Forced vibration
equipment (shakers)
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Cone penetration truck
for rapid soil
characterization
Structural sensors for
acceleration, strain,
displacement
Custom soil probes for
measuring ground
vibrations
Data Acquisition System
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Vendor: Kinemetrics, Inc.
True 24-bit resolution/large
dynamic bandwidth (155 dB)
Quanterra Q330 data loggers
are true network devices with
wireless capabilities (TCP/IP)
Powerful UNIX based data
acquisition software program,
Antelope
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Remote monitoring
Relational database
embedded
Local Area Network
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Sensors/Video
Data acquisition
system/video server
Satellite
Campus gigabit
backbone
NEESpop
Visualization portal
NEESgrid
Eccentric Mass Shakers
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MK-14A (1):
– Omni-directional
– 0 to 4.2 Hz
– 20 kips peak force
MK-15 (2):
– Uni-directional
– 0 to 25 Hz
– 100 kips peak force
– Can be synchronized
MK-14B (1):
– Omni-directional
– 0 to 10 Hz
– 50 kips peak force
– Rapidly deployable (assembly
time < 4 man hours)
Linear Inertial Shaker
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“Shake Table”
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Mounting requirements
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Table with Actuator support
System Limitations
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Mass on rails, Actuator
30 gpm HPS, Accumulators
Digital control system
Ms (weight) – 1 to 7 kips
Actuator (+/- 15 inches)
Force (15,000 pounds)
Advantages
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Random load history
Time domain analysis
Mass
m3
m2
m1
Actuator
Cone Penetration Truck
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Vendor: Hogentogler, Inc
Site characterization
Installation of soil probes
to measure ground
vibrations during forced
vibration tests of fullscale structures
Custom Soil Probes
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Deployable/retrievable
Cable
Drive shoe
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Triaxial (3 channels)
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Measure in situ ground
accelerations
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Feed directly to Q330 data
loggers
Probe
Triaxial
accelerometer
Research Vision
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Obtain detailed performance
data for linear and nonlinear
response of structural
systems
Address scale and boundary
conditions issues commonly
associated with lab studies
Provide data to study system
interactions, e.g. SFSI
Develop new sensor
(packaging) concepts
Obtain high resolution
response data to promote
advances in simulation
Shaker
To Command
Center
Soil Probes
Data
Collection
Point
Equipment Integration
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Pilot Study #1
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Pilot Study #2
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Data acquisition
Laboratory testing
Shakers, sensors,
data acquisition
Pilot Study #3
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Field testing
Soil probes (final)
Satellite system
Pilot Study #2
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SDOF steel frame
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15 ft (L) x 13 ft (H) x 6 ft (W)
Structure weight ~3.6 kips
Free-vibration testing
Forced-vibration testing
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Shaker weight ~ 5 kips
Longitudinal direction
Acceleration sensors
Strain sensors
Basic System Identification
LAN for Pilot Study #2
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Instruments: Episensors,
pulser
Antelope Workstation
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Real-time Wireless
transmission of data from
data logger in UCLA structural
laboratory to UCLA NEES
Office
Real-time transmission of
data from webserver in UCLA
NEES Office to outside world
via Antelope
Mock run (at UCLA) of real
operation scenario in the field
UCLA
CH 1-3
Conference Room
AUXILIARY
RS-232C
EXT. POWER
Terminal
Server
Antelope Workstation
Wireless
Router
Wireless
Router
CISCO SYSTEMS
UCLA NEES
Office
Router
Trailer
EM Shaker
Control
System
UCLA
Concrete Lab
Field
Legend
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Serial
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TCP/IP
Campus Gigabit Backbone
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Pilot Study #3
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PS #2 specimen on
alternative foundation
configurations
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Investigate effect on SFSI
Shaking in transverse
direction
Dense instrumentation
on structure, ground
surface and subsurface
Tele-observable Data Streams
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Excitation response
history
Recorded response
histories at sensors
Deck/foundation transfer
functions (fixed base)
Deck/foundation transfer
functions (flexible base)
8
Amplification
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10
6
4
2
0
0
2
4
6
Freq. (Hz)
8
10
Website – http://cee.ucla.edu/nees/