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Earthquake Simulation and
Near-Fault Ground Motions
Jack MoehleUC Berkeley
WWW.CONCRETE.ORG/ACI318
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WWW.CONCRETE.ORG/ACI318NCREE
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Effect of ground motion on collapse behavior
Shin, Galanis, Moehle, EESD 2016
WWW.CONCRETE.ORG/ACI318
Column detailing
(a) Old details (b) Modern details
Shin, Galanis, Moehle, EESD 2016
WWW.CONCRETE.ORG/ACI318
Sample results
Typical Modern Column Typical Older Column
Shin, Galanis, Moehle, EESD 2016
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Modern Details
Sample results
Chile
Older Details
Kobe
Shin, Galanis, Moehle, EESD 2016
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Sample results – Modern columnsHaselton et al (2006) model
0 10 20 30 40 50 60 70-6
-4
-2
0
2
4
6
Time (sec)
Dis
pla
ce
me
nt
(in
)
Top Column Displacement
Analysis
Test 3
-0.15 -0.1 -0.05 0 0.05 0.1 0.15-200
-150
-100
-50
0
50
100
150
200Column 1
Drift / Height
Ba
se
Mo
me
nt
(kip
s-i
n)
-0.15 -0.1 -0.05 0 0.05 0.1 0.15-200
-150
-100
-50
0
50
100
150
200Column 2
Drift / Height
Ba
se
Mo
me
nt
(kip
s-i
n)
0 10 20 30 40-6
-4
-2
0
2
4
6
Time (sec)
Dis
pla
ce
me
nt
(in
)
Top Column Displacement
Analysis
Test 5
-0.15 -0.1 -0.05 0 0.05 0.1 0.15-200
-150
-100
-50
0
50
100
150
200Column 1
Drift / Height
Ba
se
Mo
me
nt
(kip
s-i
n)
-0.15 -0.1 -0.05 0 0.05 0.1 0.15-200
-150
-100
-50
0
50
100
150
200Column 2
Drift / Height
Ba
se
Mo
me
nt
(kip
s-i
n)
Chile Kobe
Shin, Galanis, Moehle, EESD 2016
WWW.CONCRETE.ORG/ACI318
Sample results – Modern columnsHaselton et al (2006) model
0 10 20 30 40-6
-4
-2
0
2
4
6
Time (sec)
Dis
pla
ce
me
nt
(in
)
Top Column Displacement
Analysis
Test 5
-0.15 -0.1 -0.05 0 0.05 0.1 0.15-200
-150
-100
-50
0
50
100
150
200Column 1
Drift / Height
Ba
se
Mo
me
nt
(kip
s-i
n)
-0.15 -0.1 -0.05 0 0.05 0.1 0.15-200
-150
-100
-50
0
50
100
150
200Column 2
Drift / Height
Ba
se
Mo
me
nt
(kip
s-i
n)
Chile Kobe
Shin, Galanis, Moehle, EESD 2016
WWW.CONCRETE.ORG/ACI318
Seismic hazard analysis
ARUP
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Seismic hazard analysis
Pulse probability for T = 0.75s (0.8g)
Pulse probability for T = 7.5s (0.08g)
ARUP, based on Shahi and Baker (2011)
WWW.CONCRETE.ORG/ACI318
Seismic hazard
analysis
ARUP
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Reinforced
Concrete Frames
with High-Strength
Reinforcement
Under Near-Fault
Ground Motions
To and Moehle, ongoing, Pankow Foundation
WWW.CONCRETE.ORG/ACI318
Beam (upended)
UC Berkeley
Beam and column tests (Grade 60 to 100)
Column
UT Austin
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Test setups
Beam Test Column Test
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0
20
40
60
80
100
120
140
160
180
0.00 0.05 0.10 0.15
Stre
ss, k
si
Strain
Gr. 100 T/Y = 1.30
Gr. 100 T/Y = 1.18
Gr. 100 MMFX (A1035)
Gr. 60 T/Y = 1.50 (A615)
Gr. 60 T/Y = 1.36 (A706)
Material properties
Stre
ss, M
Pa
1000
500
0
WWW.CONCRETE.ORG/ACI318Strain profile of longitudinal bars at 4.5% Drift Ratio
Spread of plasticity
No
rmal
ized
po
siti
on
alo
ng
bea
m s
pan
Fixed end
Inflection point
WWW.CONCRETE.ORG/ACI318
Test results – Column bond failure
Sokoli and Ghannoum, ACI Structural Journal, 2016.
(a) Bond splitting cracks
ℓu
P
MV
M V
P
Cs
Cs
Ts
Ts
(b) Internal forces
Cs Plastic length
Plastic length
Bonded length
Ts
u
(c) Bond forces
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Test results – Column bond failure
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Test results - Beams
-0.06 -0.04 -0.02 0 0.02 0.04 0.06-80
-60
-40
-20
0
20
40
60
80
Drift Ratio
Late
ral F
orc
e a
t T
ip (
kip
s)
Load vs. Deflection
Initiation of Beam Twisting
-0.06 -0.04 -0.02 0 0.02 0.04 0.06-80
-60
-40
-20
0
20
40
60
80
Drift Ratio
Late
ral F
orc
e a
t T
ip (
kip
s)
Load vs. Drift Ratio
Initiation of Bar Buckling
Start of Beam Twisting
-0.06 -0.04 -0.02 0 0.02 0.04 0.06-80
-60
-40
-20
0
20
40
60
80
Drift Ratio
Late
ral F
orc
e a
t T
ip (
kip
s)
Load vs. Drift Ratio
1st Fracture of Longitudinal Bar
2nd Fracture
3rd Fracture
-0.06 -0.04 -0.02 0 0.02 0.04 0.06-80
-60
-40
-20
0
20
40
60
80
Drift Ratio
Late
ral F
orc
e a
t T
ip (
kip
s)
Load vs. Drift Ratio
Necking of Longitudinal Bars
Fracture of Longitudinal Bars
Gr. 100 – T/Y = 1.18
Gr. 100 – T/Y = 1.30Gr. 60 A706
Gr. 100 –A1035
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Archetype Frame Building (Visnjic 2014)Conventional Grade 60 Reinforcement
Archetype building design
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Hypothetical location of archetype buildings from United States
Geological Survey report (marked with bull’s eye)
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
1.60
0.00 1.00 2.00 3.00 4.00 5.00 6.00
Sa (
g)
Period (s)
DBE MCE
Pseudo-Acceleration Design Spectra
Seismic hazard
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0 1 2 3 4 5 60
0.5
1
1.5
2
2.5
3
Period (s)
Sa (
g)
Target MCE Spectrum
Average Near Fault FN-component Spectrum
Scaled Near Fault FN-component Spectra
0 1 2 3 4 5 60
0.5
1
1.5
2
2.5
3
Period (s)
Sa (
g)
Target RotD50 Spectrum
Average Near Fault FP-component Spectrum
Scaled Near Fault FP-component Spectra
Near-Fault Ground Motions
Selected and scaled ground motions
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Earthquake: Superstition Hills-02,
Station: El Centro Imp. Co. Cent
0 10 20 30 40 50 60 70-60
-40
-20
0
20
40
60
Time Series (s)
Ro
of D
isp
lace
me
nt
Gr. 60 A706
0 0.01 0.02 0.03 0.04 0.05 0.06 0.07
-150
-100
-50
0
50
100
150
Strain (in/in)
Str
ess (
ksi)
Gr. 60 A706
Stress-strain response of longitudinal
steel in one of beams
Dynamic analysis results:Roof drift history
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0 10 20 30 40 50 60 70-60
-40
-20
0
20
40
60
Time Series (s)
Ro
of D
isp
lace
me
nt
Gr. 60 A706
Gr. 100 T/Y = 1.30
0 0.01 0.02 0.03 0.04 0.05 0.06 0.07
-150
-100
-50
0
50
100
150
Strain (in/in)
Str
ess (
ksi)
Gr. 60 A706
Gr. 100 T/Y = 1.30
Earthquake: Superstition Hills-02,
Station: El Centro Imp. Co. Cent
Stress-strain response of longitudinal
steel in one of beams
Dynamic analysis results:Roof drift history
WWW.CONCRETE.ORG/ACI318
0 10 20 30 40 50 60 70-60
-40
-20
0
20
40
60
Time Series (s)
Ro
of D
isp
lace
me
nt
Gr. 60 A706
Gr. 100 T/Y = 1.30
Gr. 100 T/Y = 1.18
0 0.01 0.02 0.03 0.04 0.05 0.06 0.07
-150
-100
-50
0
50
100
150
Strain (in/in)
Str
ess (
ksi)
Gr. 60 A706
Gr. 100 T/Y = 1.30
Gr. 100 T/Y = 1.18
Earthquake: Superstition Hills-02,
Station: El Centro Imp. Co. Cent
Stress-strain response of longitudinal
steel in one of beams
Dynamic analysis results:Roof drift history
WWW.CONCRETE.ORG/ACI318
0 10 20 30 40 50 60 70-60
-40
-20
0
20
40
60
Time Series (s)
Ro
of D
isp
lace
me
nt
Gr. 60 A706
Gr. 100 T/Y = 1.30
Gr. 100 T/Y = 1.18
Gr. 100 A1035
0 0.01 0.02 0.03 0.04 0.05 0.06 0.07
-150
-100
-50
0
50
100
150
Strain (in/in)
Str
ess (
ksi)
Gr. 60 A706
Gr. 100 T/Y = 1.30
Gr. 100 T/Y = 1.18
Gr. 100 A1035
Earthquake: Superstition Hills-02,
Station: El Centro Imp. Co. Cent
Stress-strain response of longitudinal
steel in one of beams
Dynamic analysis results:Roof drift history
WWW.CONCRETE.ORG/ACI318
Average Displacement
Near-Fault Ground Motions
Fault-Normal Components
-50 -40 -30 -20 -10 0 10 20 30 40 500
0.2
0.4
0.6
0.8
1
Displacement (in)
No
rma
lize
d H
eig
ht
Gr. 60 A706
Gr. 100 T/Y = 1.30
Gr. 100 T/Y = 1.18
Gr. 100 A1035
Average Displacement
Near-Fault Ground Motions
Fault-Parallel Components
-50 -40 -30 -20 -10 0 10 20 30 40 500
0.2
0.4
0.6
0.8
1
Displacement (in)
No
rma
lize
d H
eig
ht
Gr. 60 A706
Gr. 100 T/Y = 1.30
Gr. 100 T/Y = 1.18
Gr. 100 A1035
Dynamic analysis results:Mean drifts for different reinforcement
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Average Drift Ratio
Near-Fault Ground Motions
Fault-Normal Components
Average Drift Ratio
Near-Fault Ground Motions
Fault-Parallel Components
-0.03 -0.02 -0.01 0 0.01 0.02 0.030
0.2
0.4
0.6
0.8
1
Drift Ratio
No
rma
lize
d H
eig
ht
Gr. 60 A706
Gr. 100 T/Y = 1.30
Gr. 100 T/Y = 1.18
Gr. 100 A1035
-0.03 -0.02 -0.01 0 0.01 0.02 0.030
0.2
0.4
0.6
0.8
1
Drift Ratio
No
rma
lize
d H
eig
ht
Dynamic analysis results:Mean story drift ratios for different reinforcement
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Column shears
Τℎ𝑖ℎ𝑛
2 4 6 800.0
0.2
0.4
0.6
0.8
1.0
Nonlinear Dynamic
Τ𝑉𝑖 𝐴𝑔 𝑓𝑐′, psi
0.50
Τ𝑉𝑖 𝐴𝑔 𝑓𝑐′, MPa
d 𝑉𝑢 = 𝜔Ω0𝑉𝑀𝑅𝑆𝐴
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ACI 318-19 Code Changes (tentative)
High seismic
• Permit Grade 80 (550)
– T/Y ≥ 1.17
– elongation ≥ 0.10
• Details as shown
– Grade 60
– Grade 80
150 mm6db (5db)d/4
s ≤
Hoopsalong 2hb
100 to 150 mmh/46db (5db)as required for shear
≥ 20db (26db)
≥ 2
.5l d
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Earthquake Simulation and
Near-Fault Ground Motions
Recommended