John W. van de Lindt
Colorado State University
SERIES Concluding Workshop – Joint with US-NEES
Earthquake Engineering Research Infrastructures
29 May 2013
Re-use of experimental
earthquake data for research:
Three illustrative examples
Three key ingredients for data
reuse
• Data specific to the needs of the study
• The needed accuracy for the study
• Ability to appropriately cite experimental study
Some definitions
• NEESWood: Development of a Performance-Based Seismic Design Philosophy for Mid-Rise Woodframe Construction
– PI: J. van de Lindt – 2-story house test at Buffalo by Co-PI A. Filiatrault (utilized in
NSF-funded Aftershock project, PI: Li, MTU) – 6-story apartment test at E-Defense (to be utilized in floor
diaphragm-shear wall interaction model)
– Both these represent Re-use category 1
– Re-use category 1 is defined here as “Utilization of ones own data set for a project having objectives significantly different than the project that generated the data set”
Some definitions
• Sidesway Collapse of Deteriorating Structural
Systems Under Seismic Excitations – PI: H. Krawinkler
– Scale collapse testing of steel frame at Buffalo (utilized in
NSF-funded Aftershock project, PI: Li, MTU, Co PI: van de
Lindt)
– This represents Re-use category 2
– Re-use category 2 is defined here as “Utilization of
another research teams data that was generated at a
NEES site as part of a NEESR project”
Some definitions
• Performance-Based Design of Masonry and
Masonry Veneer – PI: R. Klingner
– Reversed-cyclic tests of reinforced masonry shear walls
and transverse walls
– This represents Re-use category 3
– Re-use category 3 is defined here as “Utilization of
another research teams data that was generated at a
non-NEES site as part of a NEESR project”
Aftershocks
9
• Following large earthquakes, it’s very common to observe many
aftershocks following the mainshock: 600 aftershocks > M5.0
Japan Earthquake, 2011
Slide Credit: Li
Motivation
• Potential to cause severe
damage to buildings and
threaten life safety even
when only minor damage
is present from the
mainshock
• However, most of current
seismic risk assessment
focus on risk due to a
mainshock event only
February 2011 Christchurch earthquake
Slide Credit: Li
Aftershock Research Challenges
• Significant uncertainty in capacity of damaged buildings after main shocks
• Characteristics of aftershocks are quite complex
• Lack of system fragility models to evaluate building performance
PBE objectives
Task 1
Design portfolio
Task 2
Global-level hysteresis
damage model
Design/retrofit
options
Consider
aftershock?
PBE framework
mainshock only
Mainshock-aftershock
sequence simulation
Task 3
Fragility generation for
degrading systems
Task 4
Integration of
aftershock hazard
with PBE
Satisfied
performance
expectation?
Task 5
Illustration and Integration
into Existing
Methodologies
Numerical model
selection
Building No.
Building Type Brief Description
1 Steel Three-story steel building with ordinary moment frame
2 Steel Four-story steel building with special moment frame
3 Steel Eight-story steel building with special moment frame
4 Light-frame Wood
Two-story light commercial building
5 Light-frame Wood
Three-story apartment building
Pcollapse =
[ | ] | ( ) |aCollapseP S x dH x
Seismic Rehabilitation of Existing Buildings
Collapse Testing of Scaled Steel Frame
(Lignos and Krawinkler)
• A typical 4-story 2-bay steel moment frame is selected (1/8 scale)
SMRF.
4@30'=120'
3@
12
'=3
6'
15
'
4
3
1
2
W21X93
W21X93
W27X102
W27X102
W2
4X1
31
W2
4X7
6 W21X93
W21X93
W27X102
W27X102
Slide Credit: Li
Calibration of Prototype and Test Model
Results
Natural period in the EW direction Pushover analysis in EW direction
T1 T2 T3 Peak based shear/weight Maximum roof drift
Lignos Thesis 1.32 0.39 0.19 0.2 8.2%
Centerline model 1.32 0.44 0.24 0.2 8.2%
• The first three modal periods, pushover curve, fragility curves and
time history response of prototype and test model are calibrated
0
0.05
0.1
0.15
0.2
0.25
0.00 0.05 0.10
Bas
ed
Sh
ear
/We
igh
t
Roof Drift
Pushover Curves Lignos Result: Figure 8.1 Simulation Model
0
0.2
0.4
0.6
0.8
1
0 1 2 3 4 5
Pro
bab
ility
of
Exce
ed
en
ce
Sa (g)
Comparison of Fragility Curve
Simulated model
Lignos's result
Slide Credit: Li
Structural Collapse Capacity
• Perform incremental dynamic analysis (IDA) to determine structural
collapse capacity point defined as the last point with a tangent slope equal
to 20% of the elastic slope.
Sa=1.4g
0.0
0.4
0.8
1.2
1.6
2.0
0% 5% 10% 15%
Sa(
T1)[
g]
Maximum Interstory-drift
Collapse capacity point
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0% 5% 10% 15%
Sa(
T1)[
g]
Maximum Interstory Drift
Damaged Building from Mainshock
16
• In order to obtain the specific structural damage condition
sustained from mainshock, the intensity level of mainshock is
scaled to cause the following drift defined in ASCE/SEI 41-06
Performance Level Maximum interstory drift
Immediate occupancy (I.O.) 0.7%
Life safety (L.S.) 2.5%
Collapse prevention (C.P.) 5.0%
Structural Collapse Capacity
Difference Damage Level from Mainshock + Aftershock
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 0.05 0.1 0.15 0.2 0.25
Sp
ectr
al
acc
eler
ati
on
(g)
Drift
IDA for different damage state from MS
Only Mainshock
I.O.(0.7% from MS, Unchanged) + AS
L.S.(2.5% from MS, Unchanged) + AS
C.P.(5.0% from MS, Unchanged) + AS
Damage level sustained from
mainshock
Collapse capacity
Sa (T1)[g] Drift (%)
N/A (Only Mainshock) 1.5 12
Minor (I.O.+ AS) 1.5 12
Moderate (L.S. + AS) 1.3 12.1
Severe (C.P. + AS) 0.9 13.9
Seismic Testing of a Full-Scale Two-Story Light-Frame
Wood Building: NEESWood Benchmark Test
South-East External View of the benchmark
structure after the installation of the exterior
stucco finish
Full scale townhouse building
Floor Plans of test building
Plan view of the building
Model Development
Fitting a CUREE-type hysteretic spring
model to the global hysteresis measured
during an MCE level tri-axial shake
using the Northridge-Rinaldi ground
motion
Fitted hysteresis loop for first story
Fitted hysteresis loop for second story
Parameters First story Second story
K0 711.72 KN 289.13 KN
F0 333.62 KN 355.86 KN
F1 71.17 KN 35.59 KN
R1 0.01 0.006
R2 -0.08 -0.08
R3 0.4 1
R4 0.11 0.38
Xu 39.75 mm 39.75 mm
α 0.75 0.75
β 1.1 1.1
10 parameter of the CUREE model
Determining the Collapse Spectral Acceleration
IDA curves for a suite of 22 ground motions
IDA curve for mainshock no. 1 used for
determining collapse Sa corresponding to
collapse drift of 7%
IDA curves for 22 suite of mainshock (MCE)-
aftershock ground motions
Damage States Damage Description
Damage
State
Peak Story Drift
(%)
Wood Framing and OSB
Sheathing Gypsum Wallboard (GWB) Stucco
Minor
Damage 2 0.5-1.0
•Partial nail pull-out
• Minor splitting of top plates
• Propagation of sill plate splitting
and cracking
•Cracking of GWB and
diagonal crack propagation
at door openings
• Partial screw pull-out
• Cracking of GWB at
ceiling-wall connection
•Cracking and spalling
of stucco at garage wall
Significant
Damage 3 1.0-2.0
•Permanent differential movement
of adjacent panels
• Sheathing pull-out at wall
corners
• Major cracking and splitting of
sill and top plates
•Crushing of GWB at wall
corners
• Tape cracking of GWB
•Significant crack
propagation around
garage wall
•Cracking of stucco on
door and window
openings
•Cracking and spalling
of stucco at the corners
of the structure
Major
Damage 4 2.0-4.5
•Propagation of cracking and total
splitting of sill plates at garage
wall
• Cracking of studs above anchor
bolts
• Possible failure of anchor bolts
•Separation of parts of GWB
from the ceiling
• Buckling of GWB at door
openings Collapse Risk 5 4.5-7.0
Damage Fragilities for Mainshock-
Damaged Buildings
Damage state bands of MS(MCE)-AS scenario , (a) DS2, (b) DS3, (c) DS4, (d) DS5
Experimental Data Summary- Masonry
• Project: Performance-Based Design of Masonry and Masonry veneer.
• Authors: Richard Klingner, David McLean, Mark McGinley, Benson Shing.
• Testing twelve concrete masonry walls assemblies that were quasi-statically and dynamically tested at The University of Texas at Austin and at the NEES outdoor shake table at the University of California at San Diego.
Wall Specimens
Out of Plane motion In Plane motion
Hysteresis Configuration Out of Plane
Original Hysteresis Hysteresis fit
Hysteresis Configuration In Plane
Original Hysteresis Fit Hysteresis
Typical model for a low rise masonry structure
Our Models
Model 1 Model 2
Model 1 Drift Vs. Spectral Acceleration
Walls 1 & 2
Model 2 Drift Vs. Spectral Acceleration
Walls 3 & 4
Closure
• All projects presented here are in progress and using
data from completed and NEEShub archived projects.
• Three Data Re-use categories are defined herein
– Category 2 and 3 clearly present more challenges and in one case required direct
communication with the researcher.
– The objective is to eliminate this challenge for categories 2 and 3
• Anticipate more and more re-use over time
Thank you!
Acknowledgments
• Funding through US National Science Foundation CMMI projects 1100423 and 0529903.
• Thank you to the JRC Workshop organizers.
• Prof John W. van de Lindt