Motivation ESSI Illustrations Summary

On Modeling Uncertainty inEarthquake Soil Structure Interaction

Analysis

Boris Jeremic et al.

University of California, DavisLawrence Berkeley National Laboratory, Berkeley

ILEE Forum,Tongji University, Shanghai, China

December 2016

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Outline

Motivation

ESSI Illustrations

Summary

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Motivation

Long Term Motivation

I High fidelity seismic modeling and simulation forinfrastructure objects

I Development of an expert numerical modeling andsimulation tool

I Use of expert tool and high fidelity numerical models toanalyze seismic behavior of soil structure systems

I Predict and inform rather than (force) fit

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Motivation

ESSI Hypothesis

I Nonlinear interplay of the Earthquake, Soil and Structureplays a decisive role in successes and failures

I Timing and spatial location of energy dissipationdetermines location and amount of damage

I When we control and direct timing and spatial location ofenergy dissipation, we optimize soil structure system for

I Safety andI Economy

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Motivation

High Fidelity Predictive CapabilitiesI Verification provides evidence that the model is solved

correctly. Mathematics issue.

I Validation provides evidence that the correct model issolved. Physics issue.

I Prediction: use of computational model to foretell the stateof a physical system under consideration under conditionsfor which the computational model has not been validated.

I Prediction under uncertainty:I Modeling uncertaintyI Parametric uncertainty

I Predictive capabilities with low Kolmogorov Complexity

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Motivation

Modeling Uncertainty: Simplified ModelsI Simplified modeling: Features (important ?) are neglected

(6D ground motions, inelasticity)I Modeling Uncertainty: unrealistic and unnecessary

modeling simplificationsI Modeling simplifications: justifiable iff higher level

sophistication model shows that simplified features are notimportant

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Motivation

Parametric Uncertainty: Material and LoadsI Significant uncertainty in material and loadsI Need to propagate uncertainty through simulation, to give

regulators and engineers information for design, licensing...

5 10 15 20 25 30 35

5000

10000

15000

20000

25000

30000

SPT N Value

You

ng’s

Mod

ulus

, E (

kPa)

E = (101.125*19.3) N 0.63

−10000 0 10000

0.00002

0.00004

0.00006

0.00008

Residual (w.r.t Mean) Young’s Modulus (kPa)

Nor

mal

ized

Fre

quen

cy

Transformation of SPT N-value: 1-D Young’s modulus, E (cf. Phoon and Kulhawy (1999B))

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Motivation

Real ESSI Simulator System

I The Real ESSI Program is a 3D, nonlinear, time domain,parallel finite element program specifically developed forHi-Fi modeling and simulation of Earthquake Soil StructureInteraction problems for infrastructure objects

I The Real ESSI Computers are distributed memoryparallel computers, clusters of clusters with multipleperformance processors and networks

I The Real ESSI Notes are a hypertext documentationsystem (Theory and Formulation, Software and Hardware,Verification and Validation, Examples, and Applications)detailing modeling and simulation of ESSI problems

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Illustrations

Nuclear Power Plants: 6D or 1D Seismic MotionsI Assume that a full 6D (3D) motions at the surface are only

recorded in one horizontal directionI From such recorded motions one can develop a vertically

propagating shear wave in 1DI Apply such vertically propagating shear wave to the same

soil-structure system

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Illustrations

Development of Realistic MotionsI Free field seismic motion modelsI Sources will send both P and S waves

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Illustrations

Realistic Earthquake Motions, 6D vs 1D

I Danger of picking one component of motions (1D) from 3DI Excellent (forced) fit, but not a prediction, information is lost

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Illustrations

6D vs 1D NPP ESSI Response Comparison

Jeremic

Modeling Uncertainty for ESSI

Motivation ESSI Illustrations Summary

Summary

I Reduction of modeling uncertainty

I Development and expert use of high fidelity modeling andsimulation numerical tools: Real ESSI Simulator System

I Education and training of users (researchers, designers,regulators, owners) will prove essential

I Collaborators: Yang, Cheng, Jie, Sett, Taiebat, Tafazzoli,Karapiperis, Abell, Pisanò, Luo, Feng, Sinha, Lacour, Yang,Behbehani, Wang, Petrone, Wong, McKenna, McCallen

I Funding from and collaboration with the US-NRC, US-NSF,US-DOE, CNSC, LBNL, LLNL, INL, ILEE, AREVA NPGmbH, and Shimizu Corp. is greatly appreciated,

Jeremic

Modeling Uncertainty for ESSI