Location

San Diego, California

Session Start Date

5-24-2010

Session End Date

5-29-2010

Abstract

Based on a request by ENSI (Nuclear Regulatory Authority of Switzerland) to update the existing probabilistic earthquake hazard studies, Swissnuclear, the association of the nuclear power plants in Switzerland, initiated the PEAGASOS Project. The project started in 2001 and finished in 2004. It is for Europe a unique study, which aimed to evaluate uncertainties systematically and comprehensively. It was decided to perform the study on SSHAC-level 4. Level 4, defined by the Senior Seismic Hazard-Committee, is the highest level and was used only once before for the Yucca-Mountain-Project in the USA. In the PEGASOS Project, 21 international experts from Europe and additional supporting experts and companies from US and Europe were involved. The project was divided in 4 sub-projects representing the different steps in a seismic hazard assessment, namely seismic source characterization, attenuation relationships models, site amplification and seismic hazard calculation. ENSI closely accompanied and reviewed the project. It concluded that PEGASOS project fulfilled the requirements of a level-4-study. The assessment of site-effects and the innovative quality assurance program has set a new benchmark in seismic hazard assessment. The results have been based on the latest state of knowledge and are the best basis to assess the seismic hazard at the four nuclear power plant sites in Switzerland. It also noticed that the derived uncertainties were remarkably large and could probably be reduced by further investigations. The best candidates for reduction of uncertainties were identified in the area of attenuation models and in the site conditions studies. Therefore Swissnuclear initiated the PEGASOS Refinement Project (PRP). The paper describes in brief the project structure of the PEGASOS and the PRP, the methodology, the sensitivities of the results and the main findings. It discusses the experiences and the lessons learned by one of the site experts. The paper is mainly based on PEGASOS (2004) where more detailed information can be found.

Department(s)

Civil, Architectural and Environmental Engineering

Appears In

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Meeting Name

Fifth Conference

Publisher

Missouri University of Science and Technology

Publication Date

5-24-2010

Document Version

Final Version

Rights

© 2010 Missouri University of Science and Technology, All rights reserved.

Document Type

Article - Conference proceedings

File Type

text

Language

English

Share

COinS
 
May 24th, 12:00 AM May 29th, 12:00 AM

Site Amplification Studies for NPP Sites in Switzerland within the Project Pegasos and PRP

San Diego, California

Based on a request by ENSI (Nuclear Regulatory Authority of Switzerland) to update the existing probabilistic earthquake hazard studies, Swissnuclear, the association of the nuclear power plants in Switzerland, initiated the PEAGASOS Project. The project started in 2001 and finished in 2004. It is for Europe a unique study, which aimed to evaluate uncertainties systematically and comprehensively. It was decided to perform the study on SSHAC-level 4. Level 4, defined by the Senior Seismic Hazard-Committee, is the highest level and was used only once before for the Yucca-Mountain-Project in the USA. In the PEGASOS Project, 21 international experts from Europe and additional supporting experts and companies from US and Europe were involved. The project was divided in 4 sub-projects representing the different steps in a seismic hazard assessment, namely seismic source characterization, attenuation relationships models, site amplification and seismic hazard calculation. ENSI closely accompanied and reviewed the project. It concluded that PEGASOS project fulfilled the requirements of a level-4-study. The assessment of site-effects and the innovative quality assurance program has set a new benchmark in seismic hazard assessment. The results have been based on the latest state of knowledge and are the best basis to assess the seismic hazard at the four nuclear power plant sites in Switzerland. It also noticed that the derived uncertainties were remarkably large and could probably be reduced by further investigations. The best candidates for reduction of uncertainties were identified in the area of attenuation models and in the site conditions studies. Therefore Swissnuclear initiated the PEGASOS Refinement Project (PRP). The paper describes in brief the project structure of the PEGASOS and the PRP, the methodology, the sensitivities of the results and the main findings. It discusses the experiences and the lessons learned by one of the site experts. The paper is mainly based on PEGASOS (2004) where more detailed information can be found.