Panel Discussion: PBEE Practice and Needs Paul Somerville, URS Joe Maffei, R&C Ron Hamburger, SGH Lloyd Cluff, PG&E Tom Shantz, Caltrans Jim Malley, Degenkolb

Overview – Jim Malley Many significant accomplishments in multiple areas PBEE methodology, becomes foundation for application specific tasks Non-ductile concrete advances Ground motion work, especially NGA Procedure for quantifying system performance (ATC-63) Lifelines, bridges and systems analysis applications Life beyond NSF looks bright!

Earthquake Ground Motion Paul Somerville Lack of suitable recorded time histories for seismic design in the Western U.S. Complexity of damage patterns and the challenge of urban seismic zonation

Lack of suitable recorded time histories for seismic design The fine work of the PEER NGA Program notwithstanding, design earthquakes in most parts of the Western United States are from larger earthquakes and/or closer distances than are represented in the NGA data base Earthquake science is being applied to fill this gap, e.g. in the Tall Bldgs Initiative

We do not have recorded time histories for the design earthquake in most parts of the western United States. We need to rely on simulated time histories like those below.

Complexity of Damage Patterns - the Challenge of Urban Seismic Zonation Damage is often not simply related to surface geology – the current code approach using Vs30 for soils leaves many unexplained effects Very dense urban strong motion arrays (spacing < 1 km) combined with simulations are needed to advance our understanding of the blotchy nature of earthquake damage patterns

Northridge Earthquake Red tagged buildings occurred in clusters The Sherman Oaks cluster is not understood The Santa Monica and West LA cluster is related to the edge of the LA Basin formed by the Santa Monica fault

Earthquake Forecasting Earthquake prediction (location, time and magnitude of a specific earthquake) is not currently possible, but Earthquake forecasting (changes in likelihood of earthquakes over months to years) may soon become viable How should engineering practice respond?

Earthquake forecast for Japan just before the 2000 Tottori earthquake The forecast showed high probability for that earthquake (marked by the cross) and the 2004 Niigata Chuuetsu earthquake to the northeast

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Collapse Prediction in Evaluation Guidelines

Performance Evaluation Approach Joe’s Beer!Food! Beer!Food! Beer!Food!

Pacific Earthquake Engineering Research Center June 13, 2007 San Francisco Summative Meeting Panel Discussion: PBEE Practice and Needs Lloyd S. Cluff Pacific Gas and Electric Company Director, Earthquake Risk Management Geosciences Department Perspectives on 10 years of Earthquake Engineering Research PEER

Perspectives Strategy to establish PEER Role of California Seismic Safety Commission Role of Pacific Gas and Electric Company Lifelines component of PEER User needs-driven research agenda Public/Private/Partnerships (PPP) Leveraged funding

Accomplishments and Future Directions Accomplishments Leveraged funding PPP (PG&E, Caltrans, CEC, FEMA, BART) 1996 – 2007 ~$12.5 million Implementation of research results Useful research results that can be implemented Managing earthquake risks Improve system performance Future Directions Lifeline interdependencies during earthquakes Highways and bridges/Power utilities/Water supply System performance Individual lifelines Lifeline groups