This book presents a summary of the important outcomes of the SIGMA project related to all aspects of Probabilistic Seismic Hazard Assessment: source characterization, rock motion characterization, site response characterization, and hazard calculations, with for all of them emphasis on the treatment of uncertainties.
In recent years, attempts have been made to identify and quantify uncertainties in seismic hazard estimations for regions with moderate seismicity. These uncertainties, for which no estimation standards exist, create major difficulties and can lead to different interpretations and divergent opinions among experts. To address this matter, an international research project was launched in January 2011, by an industrial consortium composed of French and Italian organizations. This program, named SIGMA (Seismic Ground Motion Assessment) lasted for five years and involved a large number of international institutions.
This book is intended for instructors running courses on engineering seismology, graduate students in the same field and practicing engineers involved in Probabilistic Seismic Hazard Analyses.
Alain Pecker received his MSc Degree from the University of California, Berkeley, in 1973. Subsequently he worked as an engineer in the field of geosciences. He currently is professor at the Graduate School of Earthquake Engineering at the University of Pavia, Italy (since 2001) and at the Civil and Construction Engineering Department at Ecole des Ponts ParisTech, France (since 2002). He is an expert in soil mechanics and geotechnical engineering, dynamic and seismic analyses with a focus on nuclear installations, marine installations, bridges, dams-canals, among others. He is a member of a number of associations in the field and served as president of the French Association for Earthquake Engineering from 1992 to 1996. Pecker has authored or coauthored 6 books on soil dynamics and earthquake engineering and has published 48 papers in international peer reviewed journals. He was keynote speaker at a large number of conferences, among them the 14th and 15th European Conference on Earthquake Engineering in Ohrid (2010) and Istanbul (2014). He is a member of the French National Academy of Technology.
Ezio Faccioli received his MSc degree in Civil Engineering from Milan Technical University in 1964 and his PhD in Civil Engineering from the University of Illinois, USA, in 1968. Currently, he holds the position of retained consultant and partner at Studio Geotecnico Italiano srl, in Milan, Italy. He is a retired professor of Earthquake Engineering and Engineering Seismology at the Department of Structured Engineering at Politecnico di Milano, with which he had been affiliated since 1968. Faccioli was the leader of the SGI-Politecnico di Milano specialist team in the 5 year SIGMA research and development program. His main interests are engineering seismology, soil dynamics and vibration. He was member of the national working group charged with the elaboration of the current seismic zonation map of Italy, promulgated by a decree in May 2006. He co-authored 5 books has published 50 papers in international peer reviewed journals
After twenty one years of service at the International Atomic Energy Agency at various levels of responsibility, Dr. Gurpinar retired from the IAEA and started independent consulting work. He specializes in three major fields; (i) new build nuclear power plant projects focusing on selection and qualification of the site, (ii) protection of nuclear and other critical facilities against acts of sabotage, and (iii) design and evaluation of nuclear and other critical facilities against external hazards, especially earthquakes. He is a regular consultant to Worley Parsons, involved in NPP Projects in Bulgaria, Egypt, Jordan, Armenia, Poland and Turkey. He has also worked as a consultant for international organizations such as the IAEA and the European Commission. He is a current member of INSAG, the advisory group to the Director General of the IAEA. Gurpinar received his MSc in Civil Engineering from the State University of California in 1968 and his PhD in Civil Engineering with a minor in Mathematics from the University of New Mexico in 1971. He has published three books and over 150 papers in international journals or conference proceedings. He is also one of the principal authors of IAEA's Comprehensive Report on the Fukushima Daiichi accident.
Christophe Martin is a Certified Seismologist (PhD in Engineering Seismology, University of Grenoble, 1988) with over 25 years of professional experience in geoconsultancy services in the field. He provided consultancy services for a wide spectrum of multi-disciplinary infrastructure projects but currently provides specialized emphasis on nuclear power projects. He has performed regional and site investigations to assess geologic and seismic hazards for nuclear power plants, large engineered facilities, including bridges, dams, pipelines, and LNG terminals throughout France and several other countries (Algeria, Bolivia, China, Italy, Morocco, Romania, United Kingdom, among others). During the last 10 years, Martin has coordinated the revision of seismic hazard assessments for almost all nuclear sites in France. He was also actively involved in the nuclear industry working groups of the IAEA. He is author of numerous projects reports submitted to peer review by national regulators. Currently, Martin is the Project Technical Integrator for the Sinop Nuclear Site in Turkey and for the Moorside Nuclear Site in the UK.
Philippe L.A. Renault is the managing director of swissnuclear in Olten, Switzerland. He received his MSc degree in Civil Engineering from RWTH Aachen University in 2002. Subsequently, he worked as a research assistant at the same university. In 2007, he published his PhD thesis entitled "Assessment Procedure for the Evaluation of the Earthquake Safety of Bridges". He was the project manager of the Swiss seismic hazard study PEGASOS Refinement and was the head of the hazard and structural analyses group. He has authored or coauthored over 20 papers in international peer reviewed journals within the scope of his interests: structural dynamics and earthquake engineering, soil-structure interaction, impact simulations, seismic hazard assessment and seismic risk and vulnerability assessment.
1 Introduction1.1 Overview of the project organization1.2 Object of the document
2 General Concepts and PSHA Background2.1 Development of a Seismotectonic Framework for PSHA2.2 Development of Seismic Sources and Logic Trees For Source Definition2.3 Site Specific vs. Regional Study2.4 PSHA - A Framework for Seismic Source & Ground Motion & Site Response Characterization2.5 Logic Tree Approach and Treatment of Uncertainties2.5.1 Epistemic Uncertainty vs. Aleatory Variability2.5.2 Logic Tree Methodology2.5.3 Site Response2.5.4 Use of Experts2.6 Interface Issues Between Work Packages2.7 Common Required Outputs for Seismic Hazard Results2.7.1 Basic Definitions and Requirements2.7.2 Common Hazard Results2.7.3 Additional Parameters
3 Seismic source characterization3.1 Prerequisites to Develop the SSC Models3.2 Database, Earthquake Catalogue, Magnitude Conversions, Uncertainties on Metadata3.3 Seismic Source Models3.3.1 Diffuse Seismicity versus Identified Seismogenic Structures3.3.2 Seismic Source Characterization Framework3.3.3 Area Source, Fault Sources, Gridded Seismicity3.3.4 Lessons Learned Related to Seismic Source Models3.4 Occurrence Processes3.4.1 Poisson Model3.4.2 Characteristic Model3.4.3 Time-Dependent Seismicity Models3.5 Maximum Magnitude and Recurrence Parameters3.5.1 Maximum Magnitude3.5.2 Recurrence Parameters3.5.3 Lessons Learned3.6 Logic-Tree Implications3.6.1 Logic-Tree Approaches3.6.2 Efficient Tools for the Logic-Tree Conception and Weights Assignment3.6.3 Verification and Quality Assurance (QA)
4 Rock Motion Characterization4.1 Empirical Models and Point Source Stochastic Models4.1.1 Empirical Ground Motion Attenuation Models4.1.2 Point Source Stochastic Models4.2 Model Selection and Criteria4.2.1 Modelling Criteria4.2.2 Tectonic Consistency4.2.3 Site-Conditions Consistency4.3 Corrections or Modifications of Published Models4.3.1 K-Vs30 (Simulation-Based) Correction4.3.2 Data-Based Predictions for Hard Rock4.4 Standard Deviation of Model Predictions; Truncation4.4.1 Sigma Truncation4.5 Approaches for the Vertical Ground Motion Component4.6 Logic-Tree Implications4.7 Lessons Learned from the SIGMA Project
5 Site Response Characterization5.1 Soil Characterization5.1.1 Determination of the profile Natural Frequency F05.1.2 Determination of the Shear-Wave Velocity Profile and Site Class5.1.3 Seismic Instrumentation5.1.4 Characterization of Nonlinear Soil Properties5.2 Hazard Assessment at the Ground Surface5.2.1 Direct Evaluation from Ground Motion Prediction Equations (FpG)5.2.2 Generic Site Specific Approaches (HyG)5.3 Completely Site Specific Approaches (HyS)5.3.1 Linear Numerical Analyses5.3.2 Equivalent Linear Numerical Analyses5.3.3 Nonlinear Numerical Analyses5.4 Treatment of Uncertainties5.4.1 Fully Probabilistic Generic Site Approach (FpG)5.4.2 Hybrid Site Specific Approach (HyS)5.5 Lessons Learned from the SIGMA Project5.6 Additional Topics in Ground Surface Hazard Assessment5.6.1 Vertical Ground Motion5.6.2 Maximum Ground Motion: Truncation
6 Seismic Hazard Computation6.1 Basic Requirements6.2 Interfaces and Boundary Conditions6.3 Software Packages6.3.1 PSHA Software6.3.2 Site Response Analysis Codes6.4 Sensitivity Analysis6.5 Hazard Disaggregation6.6 Additional Engineering Output Parameters6.7 Selection of Time Histories6.7.1 Selection Based on UHS6.7.2 Selection Based on Conditional Spectra
7 Interfaces Between Sub Projects7.1 SSC and GMC Interfaces7.2 GMC and SRC Interfaces7.3 Single-Station Sigma7.4 V/H Models for Rock and Soil
8 Probabilistic Seismic Testing and Updating of Seismic Hazard Results8.1 PSHA Testing Using Acceleration and Macroseismic Intensity Data8.2 Bayesian Update of PSHA
9 Summary and Way Forward
11 Annex 1: List of Committee Members11.1 Steering Committee11.2 Senior Hazard Analysis Review Panel - SHARP11.3 Scientific Committee11.4 SIGMA Work Package Leaders11.5 SIGMA Partners
12 Annex 2: List of Publications12.1 Publications in International Journals with Peer Review12.2 Full Papers in Peer-Reviewed Conferences12.3 PhD Theses12.4 List of Deliverables