Download or read book Principles of Probabilistic Seismic Hazard Assessment PSHA and Site Effect Evaluation and Its Application for the Volcanic Environment in El Salvador written by Walter Salazar and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This book chapter explains the fundamental concepts of the probabilistic seismic hazard and site effect evaluation. It is divided into four parts: firstly, the theoretical background of the probabilistic seismic hazard methods is explained to compute the earthquake loads used in structural analysis of buildings, namely, the rigid-zone method, the free-zone methods, and the characteristic models. We emphasize the physical meaning of the seismic coefficient prescribed in the seismic code regulations and its association with the return period of ground motion and spectral ordinates. The interconnection of the return period, the recurrence interval, and the lifetime concepts are explained to clarify misconceptions among these terms in connection with the probability of exceedance of motion. Secondly, the seismic hazard methods are applied employing volcanic chain seismicity data, and preliminary seismic hazard maps for rock site are presented for flat topography conditions along El Salvador. Thirdly, the site effects in terms of the amplification of ground motion are studied using soil profiles characterized by the interbedding of lava flows and volcanic ashes. Finally, we present a summary that highlights the most important concepts explained in this book chapter.

Download or read book Earthquakes written by and published by BoD – Books on Demand. This book was released on 2018-10-31 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: An earthquake is the shaking of the surface of the Earth, resulting from the sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in size from those that are so weak that they cannot be felt to those violent enough to toss people around and destroy the whole cities. At the Earth's surface, earthquakes manifest themselves by shaking and sometimes displacement of the ground. When the epicenter of a large earthquake is located offshore, the seabed may be displaced sufficiently to cause a tsunami. Earthquakes can also trigger landslides and occasionally volcanic activity. Earthquakes are caused not only by rupture of geological faults but also by other events such as volcanic activity, landslides, mine blasts, and nuclear tests. This book addresses the multidisciplinary topic of earthquake hazards and risk, one of the fastest growing, relevant, and applied fields of research and study practiced within the geosciences and environment. This book addresses principles, concepts, and paradigms of earthquakes, as well as operational terms, materials, tools, techniques, and methods including processes, procedures, and implications.

Download or read book Review of Recommendations for Probabilistic Seismic Hazard Analysis written by National Research Council and published by National Academies Press. This book was released on 1997-01-06 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Probabilistic Seismic Hazard Assessment written by Hing-Ho Tsang and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Probabilistic Seismic Hazard Assessment: Direct Amplitude-based Approach" by Hing-ho, Tsang, 曾慶豪, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled "Probabilistic Seismic Hazard Assessment: Direct Amplitude-Based Approach" Submitted by TSANG HING HO for the degree of Doctor of Philosophy at The University of Hong Kong in June 2006 Conventional Probabilistic Seismic Hazard Assessment (PSHA) is difficult to apply in regions whose geological setting (including the location of active faults) is only imperfectly known. Also, for a site-specific PSHA, site effects arising from both crustal rock and overlying soil sediments are generally not assessed rigorously. This thesis demonstrates an alternative procedure for assessing seismic hazard, developed from the conventional Cornell-McGuire PSHA approach, based on considering an infinite number of sources. The proposed new procedure is termed the Direct Amplitude-Based (DAB) approach. A generic analytical solution for the proposed procedure has also been derived in this study, to avoid the need for a lengthy integration process. A site-specific ground motion attenuation model is an important element in seismic hazard assessment. Seismic attenuation behaviour is controlled by a number of wave modification mechanisms, some of which have characteristic specific to a local area or a particular site, while others can be generalised to the entire seismic region. The local seismological parameters include a crustal shear wave velocity (SWV) profile. A comprehensive methodology for modelling the SWV profile in crustal rock has been developed, enabling the amplification mechanisms in the transmission of seismic waves to be estimated. The κ parameter, which characterizes the extent of the near-surface attenuation mechanism in crustal rock, has also been investigated. Empirical correlations of κ with near-surface SWV parameters in crustal rock have been developed. This new modelling approach allows much better seismic hazard assessments to be conducted in regions of low and moderate seismicity. Site effects characterise the filtering mechanisms within the soil sedimentary layers overlying bedrock. A simple, heuristic manual procedure to calculate site amplification factor, site period shift factor and soil damping ratio has been developed. Displacement response spectra (RSD) can then be constructed for soil sites. The proposed model can take into account the nonlinear behaviour of soil that is dependent on the level of shaking, impedance contrast at the soil-bedrock interface and the plasticity of soil materials. Lastly, a case study was carried out, using Hong Kong as an example. SWV information for the four prevalent geological formations found in Hong Kong was first obtained, so as to evaluate the localised near-surface wave modification factors. A ground motion attenuation model was then developed by combining the near-surface modification factors with the regional source function of intra-plate earthquakes. Whilst the ground motion attenuation model was developed, PSHA was performed using the proposed DAB approach. Response spectral values were computed for the whole period range of engineering interest, to form a set of uniform hazard spectra for rock sites in Hong Kong. Site-specific RSD were then constructed for two representative soil and reclamation sites from different parts of Hong Kong. This case study also dealt with the estimation of the lateral building periods. By combining the period estimates with the seismic hazard mode

Download or read book American National Standard written by American Nuclear Society. Standards Committee Working Group ANS-2.29 and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ANS 2.29-2020 provides guidance for performing a probabilistic seismic hazard analysis (PSHA) for developing design and safety evaluation criteria for nuclear facilities. Criteria provided in this standard address various aspects of conducting PSHAs, including: 1. purpose, objective, and process; 2. detailed requirements; 3. PSHA framework; 4. seismic source model; 5. ground motion model; 6. site effects; 7. implementation of PSHA for seismic design and seismic probabilistic risk assessment; 8. documentation; 9. quality assurance.

Download or read book Advanced Seismic Hazard Assessment written by Giuliano Panza and published by Birkhäuser. This book was released on 2011-05-27 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues pertaining to urban risks are a pressing concern for those involved in disasters mitigation. Development of effective mitigation strategies requires sound seismic hazard information that is commonly derived through a seismic hazard assessment (SHA). The purpose of SHA is to provide a scientifically consistent estimate of seismic hazard for engineering design and other considerations. The time is ripe to move beyond the old paradigms of the traditional Probabilistic Seismic Hazard Analysis (PSHA). This two-part volume advocates advanced methods for SHA that utilize up to date earthquake science and basic scientific principles to derive the seismic hazard in terms of a ground motion or related quantity and its occurrence frequency at a site, as well as the associated uncertainty. It aims to: (1) identify the issues in the current SHAs, (2) facilitate the development of a scientifically consistent approach for SHA and (3) disseminate, both in scientific and in engineering practice societies, advanced reliable tools for independent hazard estimates, like NDSHA (neo-deterministic SHA), which incorporates physically based ground motion models. It provides a fresh approach to seismic hazard analysis. Part 1 deals with the general issues of SHA methodology review and development, as well as with recent advances in earthquake science that may have relevant implications toward an improved SHA. It is addressed to seismologists, engineers and stake-holders, and aims to contribute to bridging between modern interdisciplinary research and practitioners.

Download or read book An Introduction to Probabilistic Seismic Hazard Analysis written by J. Paul Guyer, P.E., R.A. and published by Guyer Partners. This book was released on 2020-07-22 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introductory technical guidance for civil, geotechnical and structural engineers interested in earthquake hazard analysis. Here is what is discussed: 1. OVERVIEW OF PROBABILISTIC SEISMIC HAZARD ANALYSIS (PSHA) METHODOLOGY 2. CHARACTERIZING SEISMIC SOURCES FOR PSHA 3. GROUND MOTION ATTENUATION CHARACTERIZATION FOR PSHA 4. TREATMENT OF SCIENTIFIC UNCERTAINTY IN PSHA 5. DEVELOPMENT OF SITE-SPECIFIC RESPONSE SPECTRA FROM PSHA 6. DEVELOPMENT OF ACCELEROGRAMS 7. SUMMARY OF STRENGTHS AND LIMITATIONS OF DSHA AND PSHA.

Download or read book An Introduction to Probabilistic Seismic Hazard Analysis written by J Paul Guyer and published by . This book was released on 2020-07-22 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introductory technical guidance for civil, geotechnical and structural engineers interested in earthquake hazard analysis. Here is what is discussed:1. OVERVIEW OF PROBABILISTIC SEISMIC HAZARD ANALYSIS (PSHA) METHODOLOGY2. CHARACTERIZING SEISMIC SOURCES FOR PSHA3. GROUND MOTION ATTENUATION CHARACTERIZATION FOR PSHA4. TREATMENT OF SCIENTIFIC UNCERTAINTY IN PSHA5. DEVELOPMENT OF SITE-SPECIFIC RESPONSE SPECTRA FROM PSHA6. DEVELOPMENT OF ACCELEROGRAMS7. SUMMARY OF STRENGTHS AND LIMITATIONS OF DSHA AND PSHA.

Download or read book Observation Informed Methodologies for Site Response Characterization in Probabilistic Seismic Hazard Analysis written by Kioumars Afshari and published by . This book was released on 2017 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation, we study the effects of site response on earthquake ground motions, the uncertainty in site response, and incorporating site response in probabilistic seismic hazard analysis. We introduced a guideline for evaluation of non-ergodic (site-specific) site response using (a) observations from available recorded data at the site, (b) simulations from one-dimensional ground response analysis, or (c) a combination of both. Using non-ergodic site response is expected to be an improvement in comparison to using an ergodic model which is based on the average of a global dataset conditional on site parameters used in ground motion models. The improvement in prediction when using non-ergodic analysis results in the removal of site-to-site variability which is a part of the uncertainty in ground motion prediction. The site-to-site variability is evaluated by partitioning the residuals to different sources of variability. We illustrate application of these procedures for evaluating non-ergodic site response, and use examples to show how the reduction in site response uncertainty results in less hazard for long return periods. We utilize a dataset of recordings from vertical array sites in California in order to study the effectiveness of one-dimensional ground response analysis in predicting site response. We use the California dataset for comparing the performance of linear ground response analysis to similar studies on a dataset from vertical arrays in Japan. We use surface/downhole transfer functions and amplification of pseudo-spectral acceleration to study the site response in vertical arrays. For performing linear site response analysis for the sites, we use three alternatives for small-strain soil damping namely (a) empirical models for laboratory-based soil damping; (b) an empirical model based on shear wave velocity for estimating rock quality factor; and (c) estimating damping using the difference between the spectral decay ( ) at the surface and downhole. The site response transfer functions show a better fit for California sites in comparison to the similar results on Japan. The better fit is due to different geological conditions at California and Japan vertical array sites, as well as the difference in the quality of data for the two regions. We use pseudo-spectral acceleration residuals to study the bias and dispersion of ground response analysis predictions. The results of our study shows geotechnical models for lab-based damping provide unbiased estimates of site response for most spectral periods. In addition, the between- and within-site variability of the residuals do not show a considerable regional between California and Japan vertical arrays. In another part of this dissertation, we develop ground motion models for median and standard deviation of the significant duration of earthquake ground motions from shallow crustal earthquakes in active tectonic regions. The model predicts significant durations for 5-75%, 5-95%, and 20-80% of the normalized Arias intensity, and is developed using NGA-West2 database with M3.0-7.9 events. We select recordings based on the criteria used for developing ground motion models for amplitude parameters as well as a new methodology for excluding recordings affected by noise. The model includes an M-dependent source duration term that also depends on focal mechanism. At small M, the data suggest approximately M-independent source durations that are close to 1 sec. The increase of source durations with M is slower over the range M5 to 7.2-7.4 than for larger magnitudes. We adopt an additive path term with breaks in distance scaling at 10 and 50 km. We include site terms that increase duration for decreasing VS30 and increasing basin depth. Our aleatory variability model captures decreasing between- and within-event standard deviation terms with increasing M. We use the model for validating the duration of ground motion time series produced by simulation routines implemented on the SCEC Broadband Platform. This validation is based on comparisons of median and standard deviation of simulated durations for five California events, and their trends with magnitude and distance, with our model for duration. Some misfits are observed in the median and dispersion of durations from simulated motions and their trend with magnitude and distance. Understanding the source of these misfits can help guide future improvements in the simulation routines.

Download or read book Geotechnical and Environmental Geophysics Environmental and groundwater written by Stanley H. Ward and published by . This book was released on with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Seismic Hazard Assessment written by Giuliano F. Panza and published by Birkhäuser. This book was released on 2011-05-29 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues pertaining to urban risks are a pressing concern for those involved in disasters mitigation. Development of effective mitigation strategies requires sound seismic hazard information that is commonly derived through a seismic hazard assessment (SHA). The purpose of SHA is to provide a scientifically consistent estimate of seismic hazard for engineering design and other considerations. The time is ripe to move beyond the old paradigms of the traditional Probabilistic Seismic Hazard Analysis (PSHA). This two-part volume advocates advanced methods for SHA that utilize up to date earthquake science and basic scientific principles to derive the seismic hazard in terms of a ground motion or related quantity and its occurrence frequency at a site, as well as the associated uncertainty. It aims to: (1) identify the issues in the current SHAs, (2) facilitate the development of a scientifically consistent approach for SHA and (3) disseminate, both in scientific and in engineering practice societies, advanced reliable tools for independent hazard estimates, like NDSHA (neo-deterministic SHA), which incorporates physically based ground motion models. It provides a fresh approach to seismic hazard analysis. Part 1 deals with the general issues of SHA methodology review and development, as well as with recent advances in earthquake science that may have relevant implications toward an improved SHA. It is addressed to seismologists, engineers and stake-holders, and aims to contribute to bridging between modern interdisciplinary research and practitioners.

Download or read book Probabilistic Seismic Hazard Assessment PSHA Study written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Seismic Hazard Assessment written by Giuliano Panza and published by Birkhäuser. This book was released on 2011-05-27 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues pertaining to urban risks are a pressing concern for those involved in disasters mitigation. Development of effective mitigation strategies requires sound seismic hazard information that is commonly derived through a seismic hazard assessment (SHA). The purpose of SHA is to provide a scientifically consistent estimate of seismic hazard for engineering design and other considerations. The time is ripe to move beyond the old paradigms of the traditional Probabilistic Seismic Hazard Analysis (PSHA). This two-part volume advocates advanced methods for SHA that utilize up to date earthquake science and basic scientific principles to derive the seismic hazard in terms of a ground motion or related quantity and its occurrence frequency at a site, as well as the associated uncertainty. It aims to: (1) identify the issues in the current SHAs, (2) facilitate the development of a scientifically consistent approach for SHA and (3) disseminate, both in scientific and in engineering practice societies, advanced reliable tools for independent hazard estimates, like NDSHA (neo-deterministic SHA), which incorporates physically based ground motion models. It provides a fresh approach to seismic hazard analysis. Part 2 provides advanced SHA case studies, concerning regional national and metropolitan estimates for different parts of the world, including Asia, Europe, North and South America. It is addressed to seismologists, engineers and stake-holders, and aims to contribute to bridging between modern interdisciplinary research and practitioners.

Download or read book Site Specific Seismic Hazard Analyses written by Gonzalo A. Montalva and published by LAP Lambert Academic Publishing. This book was released on 2011-12 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seismic behavior of the built environment is uncertain for a number of reasons, one of the most important of them is that surface ground motions are inherently variable. The aim of this book is to shed light on some of the variables that control much of this uncertainty, show a lower bound to this uncertainty by computing the statistics for sites (stations) that have recorded multiple earthquakes, and present the effects of plausible uncertainty reductions on the results of Probabilistic Seismic Hazard Analyses (PSHA). This book shows that single-site uncertainty is considerably lower than ergodic type uncertainty, but it cannot be used in routine PSHA without some strong pre-conditions.

Download or read book Probabilistic Seismic Hazard Analysis for Southern California Coastal Facilities written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall objective of this study was to develop probabilistic seismic hazard estimates for the coastal and offshore area of Ventura, Los Angeles and Orange counties for use as a basis for the University of Southern California (USC) to develop physical models of tsunami for the coastal regions and by the California State Lands Commission (SLC) to develop regulatory standards for seismic loading and liquefaction evaluation of marine oil terminals. The probabilistic seismic hazard analysis (PSHA) was carried out by the Lawrence Livermore National Laboratory (LLNL), in several phases over a time period of two years, following the method developed by LLNL for the estimation of seismic hazards at Department Of Energy (DOE) facilities, and for 69 locations of nuclear plants in the Eastern United States, for the Nuclear Regulatory Commission (NRC). This method consists in making maximum use of all physical data (qualitative, and quantitative) and to characterize the uncertainties by using a set of alternate spatiotemporal models of occurrence of future earthquakes, as described in the SSHAC, PSHA Guidance Document (Budnitz et al., 1997), and implemented for the NRC (Savy et al., 2002). In general, estimation of seismic hazard is based not only on our understanding of the regional tectonics and detailed characterization of the faults in the area but also on the analysis methods employed and the types of physical and empirical models that are deemed appropriate for the analysis. To develop this understanding, the body of knowledge in the scientific community is sampled in a series of workshops with a group of experts representative of the entire scientific community, including geologists and seismologists from the United States Geological Survey (USGS), members of the South California Earthquake Center (SCEC), and members of academic institutions (University of California Santa-Cruz, Stanford, UC Santa Barbara, and University of Southern California), and members of consulting firms. The purpose of the workshops was to analyze and evaluate existing data and formulate tectonic models that represent all the possible and physically valid models envisioned by the group. The basic input for the PSHA was a set of alternate earthquake source characterizations and a multi-model representation of ground motion attenuation, for adequate representation of the uncertainties. In the first phase, the physical modeling enabled rigorous analysis of uncertainty that arises from a lack of full knowledge in the characterization of both earthquake sources and ground motion. The set of ground motion prediction models included models that were updated to benefit from near field data from the most recent earthquakes (Taiwan and Turkey). The calculation were performed with LLNL computer software that is based on the Cornell, 1968 analytical model, and that propagates the knowledge uncertainties using a Monte-Carlo simulation approach (see, Bernreuter et al., 1989). Although the calculation were performed for rock-site conditions and generic soil sites, only the results for rock are given here. It is assumed that development of design parameters will include a correction of the spectral shape to reflect the site specificity. The results are for the average of the two horizontal components of the ground motion. The PSHA was calculated for thirteen sites, including two sites offshore. These sites are: Catalina Island site 1, Catalina Island site 2, Goleta, Offshore Santa-Monica, Offshore San-Clemente, Port Dume, Palos Verde site 1, Palos Verde site 2, Port of Long Beach, Port of Los Angeles, Port Hueneme, San Pedro Escarpment, and Redondo Canyon. For these thirteen sites, the hazard curves in terms of probability of exceedence of the peak ground acceleration (PGA), was calculated. In addition for Port of Long Beach, Port of Los Angeles, Santa Monica, and a site Offshore, east of San Clemente the (5% damping) uniform hazard response spectra were calculated for five Return Periods (100, 500, 1000, 2000, 10,000 year Return Periods). The detailed results are given in chapter 7.

Download or read book Review of Recommendations for Probabilistic Seismic Hazard Analysis written by National Research Council (U.S.). Panel on Seismic Hazard Evaluation and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Recommendations for Probabilistic Seismic Hazard Analysis Guidance on Uncertainty and Use of Experts written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Probabilistic Seismic Hazard Analysis (PSHA) is a methodology that estimates the likelihood that various levels of earthquake-caused ground motion will be exceeded at a given location in a given future time period. Due to large uncertainties in all the geosciences data and in their modeling, multiple model interpretations are often possible. This leads to disagreement among experts, which in the past has led to disagreement on the selection of ground motion for design at a given site. In order to review the present state-of-the-art and improve on the overall stability of the PSHA process, the U.S. Nuclear Regulatory Commission (NRC), the U.S. Department of Energy (DOE), and the Electric Power Research Institute (EPRI) co-sponsored a project to provide methodological guidance on how to perform a PSHA. The project has been carried out by a seven-member Senior Seismic Hazard Analysis Committee (SSHAC) supported by a large number other experts. The SSHAC reviewed past studies, including the Lawrence Livermore National Laboratory and the EPRI landmark PSHA studies of the 1980's and examined ways to improve on the present state-of-the-art. The Committee's most important conclusion is that differences in PSHA results are due to procedural rather than technical differences. Thus, in addition to providing a detailed documentation on state-of-the-art elements of a PSHA, this report provides a series of procedural recommendations. The role of experts is analyzed in detail. Two entities are formally defined-the Technical Integrator (TI) and the Technical Facilitator Integrator (TFI)--to account for the various levels of complexity in the technical issues and different levels of efforts needed in a given study.