Download Earthquake Engineering Experimental Facility for Research and

SERIES International Workshop
Role of Seismic Infrastructures in Seismic Rehabilitation
Earthquake Engineering Experimental Facility
for Research and Public Outreach
by
Ece Eseller-Bayat
Assistant Professor
Istanbul Technical University
Istanbul, Turkey
OUTLINE
1.
Earthquakes and Devastating Effects
2.
Reducing the Seismic Risk
3.
EQ Engineering Experimental Facility at NEU
4.
Projects conducted using the facility
5.
Public Outreach and Educational Use of the Facility
6.
Conclusion
1. Earthquakes and Devastating Effects
Adapazari EQ, 1999, M7.9 death
toll:45000
Haiti EQ, 2010, M7.0 death toll:316000
Courtesy of Ayhan Irfanoglu
Tohoku Japan EQ, 2011, M9.0 death toll:22000
Van EQ, 2011, M7.0 death toll:604
Courtesy of Reuters
Courtesy of National Turk
Courtesy of Abdurrahman Antakyali
2. Reducing the Seismic Risk
Learning from Earthquakes: Damaged and undamaged structures
Understanding earthquakes and its effects on our built environment:
Analytically and Experimentally
Finding solutions and remediation
Testing the solutions
Analytically and Experimentally
 Large-Scale Earthquake Engineering Testing Facilities are efficient in
testing more real field problems and the solutions for mitigation
3. Earthquake Engineering Measurement Facility at
Northeastern University, Boston MA
1-D Shaking Table (MTS)
 1.5 x 2.0 m
 0-50 Hz
 25 kN load capacity
 ± 12.7 cm lateral displacement
capacity
NI-DAQ data acquisition card
LAbVIEW data processing
software
3. Earthquake Engineering Measurement Facility at
Northeastern University, Boston MA
Crossbow Accelerometers
(1g, 2g, 4g)
Linear Variable Displacement
Transducer (LVDT)
PDCR 81 Miniature Pore Pressure Transducer
Pore Pressure
Transducer
Compression
Fitting with
Septum
P and S wave
measurement equipment
Bender Elements and Bender Disks
for S and P Wave Measurements
3. Earthquake Engineering Measurement Facility Cont’d
Cyclic Simple Shear Liquefaction Box (CSLLB)
Size: 19x30x45 cm
3. Earthquake Engineering Measurement Facility Cont’d
Cyclic Simple Shear Liquefaction Box (CSLLB)
Fixed to an outsider beam
2 rotating (RW) and 2 fixed
walls (FW)
Flexible sealant btw the RW,
FW and the bottom plate
 up to 1% strains
3. Earthquake Engineering Measurement Facility Cont’d
Elevation Model
Shear Strains @A-A, B-B, C-C Soil Sections
( Free Surface )
Cyclic Simple Shear
Liquefaction Box (CSLLB)
Modal analysis
Shear Strains
Elevation Model
0.0%
50
1.0%
2.0%
3.0%
B
A
C
B
A
C
45
Distance from the origin in y-direction, cm
40
35
30
25
Displacement Vectors
20
15
10
5
B-B (G-c-E-F)
A-A (G-c-E-F)
C-C (G-c-E-F)
0
4.Projects Conducted using the EQ Eng. Experimental
Facility
1.
Induced Partial Saturation (IPS) for Liquefaction Mitigation
(NSF Award #: CMS-0509894)
2.
Foundation Isolation for Seismic Protection Using a Smooth
Synthetic Liner (NSF granted)
3.
Soil Isolation for Seismic Protection Using a Smooth Synthetic
Liner (NSF granted)
4.
Evaluation of a Mechanical Isolator for Protecting Four MFA
Sculptures Against Earthquakes in Nagoya , Japan
4.Projects
1-Induced Partial Saturation (IPS) for Liquefaction Mitigation
Problem
'f = '0 - u = 0
ru= u/ '0
'f = '0 (1 - ru) = 0
1 - ru=0
ru = u/ '0 = 1
'f
Liquefaction induced bearing capacity
failure of a building after Adapazari EQ,
1999
uf = u0+ ∆u
Research Goal
Fully Saturated
Air-Entrapped Sand
Fully Saturated Sand
Air-Entrapped
Building Response in Fully
Saturated Sand
Building Response in
Air-Entrapped Sand
4.Projects
1-Induced Partial Saturation (IPS) for Liquefaction Mitigation

IPS Techniques Implemented in the Laboratory
Sodium Perborate
monohydrate
 Controllable Degree of Saturation
 Uniform Distribution of Gas Bubbles
2(NaBO3.H2O) + 2H2O
2H2O2
Hydrogen Peroxide
2H2O2 + 2BO3-3 + 2Na+ + 4H+
2H2O + O2
In Water
+
5 mm
S = 40-90%
Average Particle Size: 0.3-0.4 mm
Average Bubble Size: 0.18 mm
4.Projects
1-Induced Partial Saturation (IPS) for Liquefaction Mitigation
Integrated Experimental Setup for Evaluation of Cyclic Response of Fully and
Partially Saturated Sands
P and S wave measurement
equipment
Cyclic Simple Shear Liquefaction Box
(CSSLB)
Bender Elements and Bender Disks
for S and P Wave Measurements
Linear Variable Displacement
Transducer (LVDT)
Pore Pressure
Transducer
Compression
Fitting with
Septum
Shaking Table
PDCR 81 Pore Pressure Transducer
4.Projects
1-Induced Partial Saturation (IPS) for Liquefaction Mitigation
 Excess Pore Water Pressures in Partially Saturated Sands
Cyclic Simple Shear Strains with amplitudes
γ=0.01-0.3% applied on specimens with
 Dr=20-65%
 S=100-45%



1
(Nmax, rumax)
ru
Shear strain, γ, %
0.8
0.2
0.1
rumax is reduced as S decreases
Nmax gets larger as S decreases
S=100%
S=80%
0.6
0
0.4
-0.1
0.2
S=72%
γ=0.1%
Dr=35-40%
S=60%
-0.2
0
5
10
15
20
Number of Strain Cycles, N
25
0
0
5
10
15
20
Number of Strain Cycles, N
25
4.Projects
1-Induced Partial Saturation (IPS) for Liquefaction Mitigation
ru=f(S, Dr, γ, σ', M)
1
(Nmax, rumax)
ru
0.8
S=100%
S=80%
0.6
(N, ru)
0.4
S=72%
0.2
γ=0.1%
Dr=35-40%
S=60%
0
0
5
10
15
20
25
Number of Strain Cycles, N

1) ru max   S  e


 1 S 


 0.54 
4



(1 S ) 2



(1 S ) 2  



 2(1 S ( 0.2 ) 2 ) 2  
md

 2(1 Smg ) 2  
Dr

 
 1  8.75  ( Dr  0.2)  (1  S )  e
)  (1  S )  e
 1  1.75  ( log

0.001





 
 N 
2) ru  ru max  f 

 N max 
 N 
where f 
 is a function of S, D r ,  ,  ', M
 N max 
4.Projects
1-Induced Partial Saturation (IPS) for Liquefaction Mitigation
rumax Model
4.Projects
2-Foundation Isolation for Seismic Protection Using a Smooth
GeoSynthetic Liner
Geosynthetic
Foundation Isolator
SOIL
SOIL
ROCK
 An alternative low- cost seismic protection solution
 Within several synthetic materials tested, “geotextile/UHMWPE” found to be the most
efficient due to:
low friction coefficient (0.11) with slightly higher static friction coefficient than
dynamic friction coefficient (0.06-0.08) .
Independent of the sliding velocity, little effect of normal stress at low values (40100 kPA), number of cycles or sliding distance.
4.Projects
2-Foundation Isolation for Seismic Protection Using a Smooth
GeoSynthetic Liner
 A single story model tested under 3 records of 1989 Loma Prieta Earthquake
4.Projects
Peak Drift, cm
2-Foundation Isolation for Seismic Protection Using a Smooth
GeoSynthetic Liner
Capitola Record
0.25
0.2
0.15
0.1
0.05
0
Fixed Base
Peak Table Acceleration, g
Pe a k Dr i ft, cm
0.1
0.15
0.2
Foundation Isolation
0.25
0.3
0.35
0.4
0.45
Santa Cruz
0.25
0.2
0.15
0.1
0.05
0
Fixed Base
0.1
0.15
0.2
Foundation Isolation
0.25
0.3
0.35
0.4
Peak Table Acceleration, g
Transmitted accelerations stayed more or less around 0.1 g
The peak drift of the foundation isolated model is much smaller than the non-isolated
and remains almost constant
0.45
4.Projects
3-Soil Isolation for Seismic Protection Using a Smooth GeoSynthetic Liner
smooth synthetic liner
(a) Soil Isolation for buildings
hydraulic fill
smooth synthetic liners
(b) Soil Isolation for reclaimed land
 the liner is placed within the soil profile to absorb seismic energy before it arrives at the
ground
horizontal earthquake energy is dissipated through slip deformations along the liner
4.Projects
3-Soil Isolation for Seismic Protection Using a Smooth GeoSynthetic Liner
179 cm x 46 cm x 46 cm
Plexiglas tank
Both cylindirical and tub-shaped liners were tested and tub-shaped liner was found to be
more effective.
4.Projects
3-Soil Isolation for Seismic Protection Using a Smooth GeoSynthetic Liner
1g
1g
1
0.8
1g
1
0.8
1g
1
0.8
1
0.8
0.6
0.6
0.6
0.6
0.4
0.4
0.4
0.4
0.2
0
0.2
0
0
-0.2
0.2
0.2
0
0
-0.2
0
0
0
-0.2
-0.2
-0.4
-0.4
-0.4
-0.4
-0.6
-0.6
-0.6
-0.6
1g
-0.8
-1
0.00
5.00
10.00
15.00
20.00
25.00
30.00
0
35.00
40.00
1g
40 s
-0.8
0
5
10
15
0
20
25
30
35
40
2s
9”
acc-1
1g
-1
-1
0
5
10
15
20
25
30
35
0
40
-0.8
-1
0
5
15
20
25
30
35
40
2s
9”
5”
acc-4
acc-3
acc-2
10
0
2s
9”
sand
deposit
7”
1g
-0.8
gravel
geotextile
shaking table
table
accelerometer
CL
plexiglass
tank
UHMWPE
liner
1g
1
0.8
0.6
0.4
0.2
0
0
-0.2
-0.4
-0.6
1g
-0.8
-1
0
5
0
10
15
20
25
30
35
40
2s
Figureand
12 Acceleration
responses of tub-shaped
isolated soil
subjected
to the Santa Cruz record scaled to 0.8g.
Both harmonic
earthquake
excitations
were
applied.
Under Santa Cruz record scaled up to 0.8g, when the peak acceleration of the table was
greater than 0.2g, the peak transmitted accelerations in the central region of the sand
were much smaller than the peak table accelerations
4.Projects
3-Soil Isolation for Seismic Protection Using a Smooth GeoSynthetic Liner
Significant reductions in spectral accelerations
Side effects diminished in spectral accelerations
4.Projects
3-Soil Isolation for Seismic Protection Using a Smooth GeoSynthetic Liner
Experimental results are very important to first understand the physical behaviors
however have constrains in terms of side effects or the size of the models
Analytical studies should confirm the field scale applications
Effect of H/D on transmitted accelerations determined analytically
4.Projects
4-Evaluation
of a Mechanical
Isolator/ for
Protecting
Four
MFA
Sculptures
Nagoya
Museum, Japan
Museum
of Fine
Arts,
Boston
Against Earthquakes in Nagoya , Japan
Acceleration, g
Isolated Building Response
1
0.5
0
-0.5
-1
0
5
10
15
20
25
Time, sec
Kobe Earthquake
Acceleration, g
Kobe Earthquake (scaled)
1
0.5
0
-0.5
-1
0
5
10
15
Time, sec
20
25
30
4
30
4.Projects
4-Evaluation of a Mechanical Isolator for Protecting Four MFA Sculptures
Against Earthquakes in Nagoya , Japan
Non- Isolated Museum Building
Displacement, cm
Displacement, cm
Isolated Museum Building
15
10
5
0
-5
-10
-15
0
5
10
15
20
25
15
10
5
0
-5
-10
-15
0
30
5
10
Acceleration, g
Acceleration, g
1
0.5
0
-0.5
-1
0
5
10
15
15
20
25
0
5
10
15
Time, sec
No Building
Isolation
20
25
30
Acceleration, g
Acceleration, g
15
Time, sec
25
30
-1
Kobe Earthquake
10
20
0
-0.5
Kobe Earthquake
5
30
1
30
Building Isolation
0
25
0.5
Time, sec
1
0.5
0
-0.5
-1
20
Time, sec
Time, sec
1
0.5
0
-0.5
-1
0
5
10
15
Time, sec
20
25
30
4.Projects
4-Evaluation of a Mechanical Isolator for Protecting Four MFA Sculptures
Against Earthquakes in Nagoya , Japan
Equivalent
Sculpture
Weight
Mechanical Isolator, MI
Shaking Table
4.Projects
4-Evaluation of a Mechanical Isolator for Protecting Four MFA Sculptures
Against Earthquakes in Nagoya , Japan
5. Public Outreach and Educational Use of the Facility
To raise awareness and interest of Women, Minorities, Middle and High School Students
in Engineering and Earthquakes
5. Public Outreach and Educational Use of the Facility
NSF Young Scholar Program : High school students spend 6 weeks in summer in research
5. Public Outreach and Educational Use of the Facility
In Earthquake Engineering Lectures
6. Conclusion
Earthquake Engineering Experimental Facility is essential in seismic rehabilitation since
it can
 provide high quality data that can advance fundamental knowledge of the behavior
of geotechnical and structural elements,
 validate analytical models
 help explore development of innovative, cost-effective seismic mitigation
technologies
 encourages educational and outreach activities and awareness of earthquake risk
 demonstrate the important role engineers play in seismic mitigation
Thank you
6.Detection and Long-Term Sustainability of Entrapped
Air/Gas
Tests performed under hydrostatic, vertical and horizontal hydraulic gradient flow.
100
100
Water
∆H
S, %
Constant Heads
150
Sinitial = 81.7%
Sfinal = 83.8%
95
90
Constant Head
85
80
Constant Head
Inflow Water100
80
0
60
7.62 cm (3")
Plexiglass40
Tube
40
60
80
Time (week) Excess
(b)
S, %
-20 -10 0
85
10 20
80
Outflow
Water
Plexiglass Tube
Gravel
Filter
50
90
ΔH
Water
120
einitial= 0.74
efinal = 0.68
Sinitial
= 85.4%
Plastic
Sfinal
= 86%
Sleeves
95
120
cm
100
Water Out
100
Partially 20
Saturated
Ottawa Sand
0
Column
Lateral Partially Saturated
Ottowa Sand Layer
0
191.5 cm
Elbow
0
50
100
150
200
Drainage Beaker
0
-20
0.2
Gradient, i
0.4
250 Lateral
Shelf300
0.6
(c)
Reinforced
Concrete -40
Column
100
95
-80
(a)
Degree of Saturation, S (%)
S, %
Gravel -60
Filter
-100
20
14.65 cm 40.5 cm

90
100
85
80
95
1
10
100
1000
N
90
0 - 0.7 g
einitial = 0.72
efinal = 0.73
Sinitial100000
= 82.6%
10000
Sfinal = 83.6%
Air bubbles stayed entrapped
even during long-term high
gradient flow tests.

0.99 g
(d)
85
80
0
0.1
0.2
0.3
Gradient, i
0.4
0.5
0.6
6. Long-Term Sustainability of Entrapped Air/Gas
Penetration
of casing
Rack and pinion
drive unit
Construction of
sand pile
(Sand Pile
completed)
Sand
Air pressure
(500kPa)
Motor
Casing
pipe
Evidence on long-term sustainability of air from
Mitsu Okamura's study :
Exhausted
air
Trace of
casing tip
Sand
compaction
pile
Improved sand
 Tested samples taken from SCP treated sites, after
4 yrs, 8yrs and 26 yrs.
Soil Improved with Soil Compaction Pile (SCP) Technique
from Mitsu Okamura, 2005
Hitotsuya (4 years)
Moriya (8 years)
Sekiya (26 years)
 Air entrapped in the voids of granular soils
for a long time.
Degree of saturation, S (%)
 Evaluated degree of saturation.
shortly after SCP
100
90
80
70
0.001
0.01
0.1
10% diameter, D10 (mm)
from Mitsu Okamura, 2005
1