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

• jwv@engr.colostate.edu