Next Generation Attenuation Models for Central & Eastern US (NGA-East)

Stakeholder Workshop: Introduction

March 7, 2008

Yousef Bozorgnia, Ph.D., P.E.

PEER Associate Director

Acknowledgments

Nuclear Regulatory Commission (NRC)

US Geological Survey (USGS)

National Institute of Standards & Technology (NIST)

Agenda9:00 Introduction (Yousef Bozorgnia)9:15 NRC Perspective for NGA-East (Ann Kammerer, Jon Ake)9:35 Need for NGA-East: National Hazard Maps for CEUS; Status, Plans, and

Issues (Mark Petersen)10:10 Need for NGA-East: EPRI CEUS Ground Motion Report; Summary and

Issues (Norm Abrahamson)

10:45 Break

11:00 Need for NGA-East: Issues Related to Ground Motion Database forCEUS (Chris Cramer)

11:35 Need for NGA-East: Recent Developments in Ground MotionSimulations for CEUS (Paul Somerville/Rob Graves)

12:10 Lunch

1:10 Need for NGA-East: Recent Developments in Ground Motion Modelsfor CEUS (Ken Campbell)

1:45 Review of Tentative Plan for NGA-East (Ann Kammerer, Jon Ake,Yousef Bozorgnia, Ken Campbell, Norm Abrahamson)

2:20 Discussions (All)3:00 Adjourn

Purpose of This Stakeholder Workshop

To give an overview of: Current status of ground motion (GM)

estimates in CEUS Recent developments in GM

predictions in CEUS Tentative plan for NGA-East

To invite you to join NGA-East: As a co-sponsor In the planning phase, or technical

phase

Need for NGA-EastFor CEUS, the attenuation models are a major source of uncertainty for seismic hazard calculations. This can be improved by: Expanding a database of recorded

ground motions recorded in, and simulated for, Stable Continental Regions

A coordinated effort to develop a consistent, yet independent, set of attenuation models for CEUS

Including supporting R&D efforts

This Follows Successful Program of NGA-West

A multidisciplinary program, coordinated over five years

Bringing together: geologists,

seismologists, geotechnical engineers, structural engineers, and users of ground motion models

Researchers, and practitioners

USGS

Private Industry

Caltrans

Private Industry

USGS

UC Berkele

y

UC Santa

BarbaraSan

Diego State

U.

U. Nevada

Student

There are more than 100 variables describing source/path/site conditions of a record:

6 types of distance measures

4 site classification schemes

Estimated VS30 for most of recording sites

HW/FW classesThe database is fully available to the public

Compiled One of the Largest Uniformly-Processed Strong-Motion Databases in the World

Ground motion parameters:

Horizontal components

PGA, PGV, PGD

Pseudo spectral acceleration

Period: 0 - 10 sec

NGA-West Attenuation Models

Magnitude range: 5.0 - 8.0+

Fault Mechanism: Strike-Slip Reverse Normal

Site EffectsVs30 , Basin/Sediment depth

Distance range: 0 – 200 km

NGA-West & National Seismic Hazard Maps

USGS has extensively reviewed NGA, and is adopting the NGA models for the US National Seismic Hazard Maps

Period=1.0 sec Spectral Acceleration2% P.E. in 50 years

Ratio of New/Old:Using 3 NGA relationsVersus:2002 Hazard MapsAbrahamson and Silva (1997),Sadigh et al. (1997), Boore et al. (1997),Campbell and Bozorgnia (2003),Spudich et al. (1999) for extensionalareas

Preliminary Map

NGA-East

It is in the planning stageThere was one technical meeting A List of many supporting R&D projects were compiledThere will be a public meeting in April/MayMay/June, 2008, a “road map” report for NGA-East will be submitted to the NRC and other potential funding agencies

NGA-East (cont’d)

The “road map” report will include: A timeline for the overall NGA-East

program (a five-year program) List of supporting R&D projects Estimated budget

…later today we will elaborate on tentative plan for NGA-East

Agenda9:00 Introduction (Yousef Bozorgnia)9:15 NRC Perspective for NGA-East (Ann Kammerer, Jon Ake)9:35 Need for NGA-East: National Hazard Maps for CEUS; Status, Plans, and

Issues (Mark Petersen)10:10 Need for NGA-East: EPRI CEUS Ground Motion Report; Summary and

Issues (Norm Abrahamson)

10:45 Break

11:00 Need for NGA-East: Issues Related to Ground Motion Database forCEUS (Chris Cramer)

11:35 Need for NGA-East: Recent Developments in Ground MotionSimulations for CEUS (Paul Somerville/Rob Graves)

12:10 Lunch

1:10 Need for NGA-East: Recent Developments in Ground Motion Modelsfor CEUS (Ken Campbell)

1:45 Review of Tentative Plan for NGA-East (Ann Kammerer, Jon Ake,Yousef Bozorgnia, Ken Campbell, Norm Abrahamson)

2:20 Discussions (All)3:00 Adjourn