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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
The Nonlinear Time-Domain Modeling ofEarthquake Soil Structure Interaction forNuclear Power Plants: Nonlinear Contact
Between Foundation and Rock
B. Jeremic, A. Kammerer, N. Tafazzoli, B. Kamrani,
University of California, Davis, CALawrence Berkeley National Laboratory, Berkeley, CAU.S. Nuclear Regulatory Commission, Washington DC
SMiRT 21, New Delhi, India, November 2011
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
Outline
Introduction
Foundation – Soil/Rock InterfaceThe ProblemThe Modeling
Nonlinear Interface Results/IssuesVertically Propagating Earthquake3D Synthetic Ricker Wavelet
Summary
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
Page 3
Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
Outline
Introduction
Foundation – Soil/Rock InterfaceThe ProblemThe Modeling
Nonlinear Interface Results/IssuesVertically Propagating Earthquake3D Synthetic Ricker Wavelet
Summary
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
Introduction
I High fidelity modeling and simulation of earthquakesoil/rock structure interaction behavior of NPPs
I Reduction of modeling uncertainty
I Focus in this study are nonlinear material effects at thefoundation – soil/rock interface
I Thanks to Dr. Godoy and Dr. Kennedy for pointing out tothis issue/problem
I One of the case studies for the NRC ESSI SimulatorSystem
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
Page 5
Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
Outline
Introduction
Foundation – Soil/Rock InterfaceThe ProblemThe Modeling
Nonlinear Interface Results/IssuesVertically Propagating Earthquake3D Synthetic Ricker Wavelet
Summary
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
The Problem
Foundation – Soil/Rock Interface
I The case of nonlinear, elastic-plastic zone between aconcrete slab and a foundation soil/rock.
I Layers of plastic waterproof sheets in the zone
I Reduction of capacity for horizontal shear a thefoundation-rock contact
I Possible gaping, opening and closing (hard or soft)
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
The Problem
Beneficial and/or Detrimental ?
I Benefits of nonlinear contact between the foundation slaband the soil/rock
I Dissipation (significant) of seismic energy (shear)I Change of seismic motions characteristics (frequency
reduction)I "Passive" base isolation
I Detriments of nonlinear contact between the foundationslab and the soil/rock
I Gap opening with hard gap closing (high frequency load)I Change of seismic motions
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
The Modeling
Contact Element
I Node to node contact element
I General, 3D element
I Gap opening/closing in normal direction
I Frictional contact in shear direction
I Viscous and/or non-viscous gap opening/closing
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
The Modeling
Verification and ValidationVerification provides evidence that the model is solved correctly.
I Code verificationI Finite elementsI Constitutive simulationsI Static and dynamic solution advancement algorithmsI SolversI Wave propagationI Model/mesh verification
Validation provides evidence that the correct model is solved.
I Validate components, unit testsI Validate the system (limited data, recent earthquakes)
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
The Modeling
ESSI Model, with/without Interface
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
The Modeling
Model VerificationI Verification: finite element mesh, wave propagation
I Synthetic motions: Ricker, Ormsby wavelets
I Verify propagation of Body (P, SV and SH) and Surface(Rayleigh, Love) waves
2km10km
5km
x
y
xy
1
1
22
2km
0.2km
0 0 2 4 6 8 10 12
Time (s)
0.2 m/s2
z=3000m
z=3200m
z=3400m
z=3600m
z=3800m
z=4000m
z=4200m
z=4400m
z=4600m
z=4800m
z=5000m
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
Outline
Introduction
Foundation – Soil/Rock InterfaceThe ProblemThe Modeling
Nonlinear Interface Results/IssuesVertically Propagating Earthquake3D Synthetic Ricker Wavelet
Summary
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
Influence of Inelastic Foundation-Soil/Rock Contact onthe NPP Response
I Soil/rock – foundation interface slip behavior
I Changes in Earthquake Soil/Rock Structure Interaction(reduction/increase in demand)
I Dissipation of seismic energy in the slip plane
I Passive (and active) base isolation
I Two examples, 1D seismic wave and 3D synthetic Rickerwavelet
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
Vertically Propagating Earthquake
Incident Earthquake SV Wave
-5
-4
-3
-2
-1
0
1
2
0 0.5 1 1.5 2 2.5 3 3.5 4
Acc
eler
atio
n (m
/s2 )
Time (s)
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
Vertically Propagating Earthquake
Base and Top of the Containment
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0 5 10 15 20
FF
T F
unct
ion
Am
plitu
de
Frequency (Hz)
0
0.05
0.1
0.15
0.2
0.25
0 5 10 15 20F
FT
Fun
ctio
n A
mpl
itude
Frequency (Hz)
—slip —noslip
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
3D Synthetic Ricker Wavelet
Incident Ricker Wavelet at 45o
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
3D Synthetic Ricker Wavelet
ESSI with Slip, Base, Accelerations FFT
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
FF
T F
unct
ion
Am
plitu
de
Frequency (Hz)
Slip BehaviorNo-Slip Behavior
0
0.1
0.2
0.3
0.4
0.5
0.6
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
Dis
plac
emen
t (m
)
Frequency (Hz)
Slip BehaviorNo-Slip Behavior
horizontal Acc. FFT vertical acc. FFT
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
3D Synthetic Ricker Wavelet
ESSI with Slip, Top, Accelerations FFT
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
0.11
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
FF
T F
unct
ion
Am
plitu
de
Frequency (Hz)
Slip BehaviorNo-Slip Behavior
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
Dis
plac
emen
t (m
)
Frequency (Hz)
Slip BehaviorNo-Slip Behavior
horizontal acc. FFT vertical acc. FFT
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
Page 19
Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
Outline
Introduction
Foundation – Soil/Rock InterfaceThe ProblemThe Modeling
Nonlinear Interface Results/IssuesVertically Propagating Earthquake3D Synthetic Ricker Wavelet
Summary
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip
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Introduction Foundation – Soil/Rock Interface Nonlinear Interface Results/Issues Summary
Summary
I Nonlinear behavior of the foundation – soil/rock interfacezone can have beneficial and detrimental effects on theseismic response of NPPs
I Beneficial or Detrimental, such nonlinear interface doesexists and has to be properly modeled
I High fidelity numerical prediction relies heavily on properverification and validation
I Information Portal:http://nrc-essi-simulator.info
I Funding by and Collaboration with the U.S.-NRC isgratefully acknowledged
Jeremic et al.
Nonlinear ESSI of NPPs with Contact Slip