Download or read book Utilization of Physics based Simulated Earthquake Ground Motions for Performance Assessment of Tall Buildings written by Nenad Bijelić and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Databases of recorded motion are limited despite the increasing amount of data collected through strong motion instrumentation programs. Particular lack of data exists for large magnitude events and at close distances as well as on earthquakes in deep sedimentary basins. Additionally, databases of recorded motions are also limited in representation of energy at long periods due to the useable frequencies of recording instruments. This lack of data is currently partially addressed through assumption of ergodicity in development of empirical ground motion prediction equations (GMPEs). Nevertheless, challenges remain for calibration of empirical GMPEs as used in conventional approaches for probabilistic estimation of seismic hazard. At the same time, limited data on strong earthquakes and their effect on structures poses challenges for making reliable risk assessments particularly for tall buildings. For instance, while the collapse safety of tall buildings is likely controlled by large magnitude earthquakes with long du- rations and high long-period content, there are few available recorded ground motions to evaluate these issues. The influence of geologic basins on amplifying ground motion effects raises additional questions. Absent recorded motions from past large magnitude earthquakes, physics-based ground motion simulations provide a viable alternative due to the ability to consider extreme ground motions while being inherently site-specific and explicitly considering instances not well constrained by limited empirical data. This thesis focuses on utilization of physics-based simulated earthquake ground motions for performance assessment of tall buildings with three main goals: (1) developing confidence in the use of simulated ground motions through comparative assessments of recorded and simulated motions; (2) identifying important characteristics of extreme ground motions for col- lapse safety of tall buildings; (3) exploring areas where simulated ground motions provide significant advantages over recorded motions for performance-based engineering. To gain confidence in the use of simulated motions for full performance assessment of tall buildings, a 'similar intensity measure' validation study was performed. Structural responses to ground motions simulated with different methods on the Southern California Earthquake Center (SCEC) Broadband Platform (BBP) are contrasted to recorded motions from PEER NGA database with similar spectral shape and significant durations. Two tall buildings, a 20-story concrete frame and a 42-story concrete core wall building, are analyzed at increasing levels of ground motion intensity, up to structural collapse, to check for statistically significant differences between the responses to simulated and recorded motions. Considered demands include story drift ratios, floor accelerations and collapse response. These comparisons yield similar results in most cases but also reveal instances where certain simulated ground motions can result in biased responses. The source of bias is traced to differences in correlations of spectral values in some of the stochastic ground motion simulations. When the differences in correlations are removed, simulated and recorded motions yield comparable results. Moving beyond validation, the thesis also explored areas where the use of simulated motions provides advantages over approaches based on limited databases of recorded motions for performance-based engineering. One such area is seismic risk in deep sedimentary basins which is studied by examining collapse risk and drift demands of a 20-story archetype tall building utilizing ground motions at four sites in the Los Angeles basin. Seismic demands of the building are calculated form nonlinear structural analyses using large datasets (~500,000 ground motions per site) of unscaled, site-specific simulated seismograms. Seismic hazard and building performance from direct analysis of SCEC CyberShake motions are contrasted with values obtained based on 'conventional' approaches that rely on recorded motions coupled with probabilistic seismic hazard assessments. The analysis shows that, depending on the location of the site within the basin, the two approaches can yield drastically different results. For instance, at a deep basin site the CyberShake-based analysis yields around seven times larger mean annual frequency of collapse ( c) and significantly higher drift demands (e.g. drift demand of 1% is exceeded around three times more frequently) compared to the conventional approach. Both the hazard as well as the spectral shapes of the motions are shown to drive the differences in responses. Deaggregation of collapse risk is performed to identify the relative contributions of earthquake fault ruptures, linking building responses with specific seismograms and contrasting collapse risk with hazard. The effect of earthquake ground motions in deep sedimentary basins on structural collapse risk is further studied through the use of CyberShake earthquake simulations in the Los Angeles basin. Distinctive waveform characteristics of deep basin seismograms are used to classify the ground motions into several archetype groups, and the damaging influence of the basin effects are evaluated by comparing nonlinear structural responses under comparable basin and non-basin ground motions. The deep basin ground motions are observed to have larger durations and spectral intensities than non-basin motions for vibration periods longer than about 1.5 seconds, which can increase the relative structural collapse risk by up to 20 percent between ground motions with otherwise comparable spectral accelerations and significant durations. Two new metrics, termed sustained amplitude response spectra (RSx spectra) and significant duration spectra (Da spectra), are proposed to quantify period-dependent duration effects that are not otherwise captured by conventional ground motion intensity measures. The proposed sustained amplitude response spectra and significant duration spectra show promise for characterizing the damaging effects of long duration features of basin ground motions on buildings and other structures. The large database of CyberShake simulations is utilized to re-examine the relationships between engineering demand parameters and input ground motions on structural response. Focusing on collapse response, machine learning techniques are applied to results of about two million nonlinear time history analyses of an archetype 20-story tall building performed using CyberShake ground motions. The resulting feature selection (based on regularized logistic regression) generally confirms existing understanding of collapse predictors as gained from scaled recorded motions but also reveals the benefit of some novel intensity measures (IMs), in particular the RSx spectral features. In addition, the statistical interrogations of the large collection of hazard-consistent simulations demonstrate the utility of different IMs for collapse predictions in a way that is not possible with recorded motions. A small subset of robust IMs is identified and used in development of an efficient collapse classification algorithm, which is tested on benchmark results from other CyberShake sites. The classification algorithm yields promising results for application to regional risk assessment of building performance.

Download or read book Encyclopedia of Earthquake Engineering written by Michael Beer and published by Springer. This book was released on 2016-01-30 with total page 3953 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Encyclopedia of Earthquake Engineering is designed to be the authoritative and comprehensive reference covering all major aspects of the science of earthquake engineering, specifically focusing on the interaction between earthquakes and infrastructure. The encyclopedia comprises approximately 300 contributions. Since earthquake engineering deals with the interaction between earthquake disturbances and the built infrastructure, the emphasis is on basic design processes important to both non-specialists and engineers so that readers become suitably well informed without needing to deal with the details of specialist understanding. The encyclopedia’s content provides technically-inclined and informed readers about the ways in which earthquakes can affect our infrastructure and how engineers would go about designing against, mitigating and remediating these effects. The coverage ranges from buildings, foundations, underground construction, lifelines and bridges, roads, embankments and slopes. The encyclopedia also aims to provide cross-disciplinary and cross-domain information to domain-experts. This is the first single reference encyclopedia of this breadth and scope that brings together the science, engineering and technological aspects of earthquakes and structures.

Download or read book Proceedings of the 7th International Conference on Earthquake Engineering and Seismology written by Murat Altug Erberik and published by Springer Nature. This book was released on with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ground Motion Simulation Validation Based on Loss Metrics written by Poojitha Shashi and published by . This book was released on 2017 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of the earthquake ground motion parameters on the probabilistic loss estimation of buildings is the major interest of this study. For the seismic performance assessment, real ground motion records from the past earthquakes are required. Estimation of repair costs in future earthquakes is the major component for seismic loss analysis. This study addresses the sensitivity of the statistical characteristics of ground motions contributing to the building loss. Among these characteristics are the ground-shaking intensity (Arias Intensity), duration, and frequency at the middle of strong-shaking phase of the ground motion. These parameters are vital in determining the seismic response of the building structure. A fine study on the sensitivity of the seismic response and corresponding loss of the building structure to ground motions model parameters is carried out using Performance-based Earth- quake Engineering and Performance Assessment Computational Tool, respectively. But due to the scarcity of moderate to large earthquakes, the real records fail to match the required characteristics of motions, as there are insufficient set of data available for analysis to be carried out. Even, the of technique scaling ground motions results in overall unrealistic properties. This has led to the simulation of ground motions which will provide the additional and hopefully accurate predicted information on characteristics of the moderate to large earthquakes. Hence, a fully non-stationary stochastic model for strong earthquake ground motion model is considered which employs the statistical characteristics (waveform parameters) as model parameters matched with those of identified for a large sample of recorded ground motions for specified earthquake and site characteristics, to deliver simulated ground motions to examine the building loss metrics, which depends on the uncertainties in various analysis process starting from obtaining Intensity Measure (IM), Demand parameters (EDPs) to the repair cost estimates. From the predictive equations, specified earthquake and site characteristics results in the model parameters.Further, the validity of simulated ground motion time series representing the real ground shaking during future earthquakes is a crucial step. This study employs the hybrid broad- band ground motion simulation applied simulations to validate against the real records. With the help of hybrid approach, making use of wave propagation phenomena and site response characterization, effort has been taken for validation of these simulated ground motions is conducted for the sensitivity of seismic response and loss for these simulated ground motions.

Download or read book Integrated Earthquake Simulation written by M. Hori and published by CRC Press. This book was released on 2022-09-26 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Integrated earthquake simulation (IES) is a new method for evaluating earthquake hazards and disasters induced in cities and urban areas. It utilises a sequence of numerical simulations of such aspects as earthquake wave propagation, ground motion amplification, structural seismic response, and mass evacuation. This book covers the basics of numerical analysis methods of solving wave equations, analyzing structural responses, and developing agent models for mass evaluation, which are implemented in IES. IES makes use of Monte-Carlo simulation, which takes account of the effects of uncertainties related to earthquake scenarios and the modeling of structures both above and below ground, and facilitates a better estimate of overall earthquake and disaster hazard. It also presents the recent achievement of enhancing IES with high-performance computing capability that can make use of automated models which employ various numerical analysis methods. Detailed examples of IES for the Tokyo Metropolis Earthquake and the Nankai Trough Earthquake are given, which use large scale analysis models of actual cities and urban areas.

Download or read book Stochastic Model for Earthquake Ground Motion Using Wavelet Packets written by Yoshifumi Yamamoto and published by Stanford University. This book was released on 2011 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: For performance-based design, nonlinear dynamic structural analysis for various types of input ground motions is required. Stochastic (simulated) ground motions are sometimes useful as input motions, because unlike recorded motions they are not limited in number and because their properties can be varied systematically to study the impact of ground motion properties on structural response. This dissertation describes an approach by which the wavelet packet transform can be used to characterize complex time-varying earthquake ground motions, and it illustrates the potential benefits of such an approach in a variety of earthquake engineering applications. The proposed model is based on Thr´ainsson and Kiremidjian (2002), which use Fourier amplitudes and phase differences to simulate ground motions and attenuation models to their model parameters. We extend their model using wavelet packet transform since it can control the time and frequency characteristic of time series. The time- and frequency-varying properties of real ground motions can be captured using wavelet packets, so a model is developed that requires only 13 parameters to describe a given ground motion. These 13 parameters are then related to seismological variables such as earthquake magnitude, distance, and site condition, through regression analysis that captures trends in mean values, standard deviations and correlations of these parameters observed in a large database of recorded strong ground motions. The resulting regression equations then form a model that can be used to predict ground motions for a future earthquake scenario; this model is analogous to widely used empirical ground motion prediction models (formerly called "attenuation models") except that this model predicts entire time series rather than only response spectra. The ground motions produced using this predictive model are explored in detail, and are shown to have elastic response spectra, inelastic response spectra, durations, mean periods, etc., that are consistent in both mean and variability to existing published predictive models for those properties. That consistency allows the proposed model to be used in place of existing models for probabilistic seismic hazard analysis (PSHA) calculations. This new way to calculate PSHA is termed "simulation-based probabilistic seismic hazard analysis" and it allows a deeper understanding of ground motion hazard and hazard deaggregation than is possible with traditional PSHA because it produces a suite of potential ground motion time histories rather than simply a distribution of response spectra. The potential benefits of this approach are demonstrated and explored in detail. Taking this analysis even further, this suite of time histories can be used as input for nonlinear dynamic analysis of structures, to perform a risk analysis (i.e., "probabilistic seismic demand analysis") that allows computation of the probability of the structure exceeding some level of response in a future earthquake. These risk calculations are often performed today using small sets of scaled recorded ground motions, but that approach requires a variety of assumptions regarding important properties of ground motions, the impacts of ground motion scaling, etc. The approach proposed here facilitates examination of those assumptions, and provides a variety of other relevant information not obtainable by that traditional approach.

Download or read book Ground Motion Simulations written by Lynne Schleiffarth Burks and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Engineers use earthquake ground motions for a variety of reasons, including seismic hazard assessment, calibration of ground motion prediction equations (GMPEs), and input to nonlinear response history analysis. These analyses require a significant number of ground motions and for some scenarios, such as earthquakes with large magnitudes and short distances, it may be difficult to obtain a sufficient number of ground motion recordings. When sufficient recordings do not exist, engineers modify available recordings using scaling or spectrum matching, or they use ground motion simulations. Ground motion simulations have existed for decades, but recent advances in simulation methods due to improved source characterization and wave propagation, coupled with increased computing power, have increased potential benefits for engineers. But before simulations can be used in engineering applications, simulations must be accessible and consistent with natural observations. This dissertation contributes to the latter issue, and it investigates the application of simulations to specific engineering problems. The Southern California Earthquake Center (SCEC) Broadband Platform (BBP) is an open-source software distribution that enables third-party users to simulate ground motions using research code contributed by model developers. Because the BBP allows users to compute their own simulations with little knowledge of the underlying implementation and it ensures that all calculations are reproducible, it is extremely valuable for simulation validation and engineering applications. In this dissertation, the BBP is evaluated as a simulation generation tool from an engineering perspective. Ground motions are simulated to study parameters of engineering interest, such as high-frequency variability, near-fault ground motions, and local site response. Though some parameters need further development, such as site response (which is currently implemented using simple empirical amplification), the BBP proves to be an effective tool for facilitating these types of engineering studies. This dissertation proposes a simulation validation framework based on simple and robust proxies for the response of more complicated structures. We compile a list of proxies with robust empirical models that are insensitive to changes in earthquake scenario and do not rely on extrapolation for rarely observed events. Because predictions of these proxies are reliable under a variety of earthquake events, we can confidently compare them with simulations. The proposed proxies include correlation of epsilon across periods, ratio of maximum to median response across horizontal orientations, and ratio of inelastic to elastic displacement. The validation framework is applied to example simulations and successfully exposes some parameters that need work, such as variability and correlation of spectral acceleration. Finally, this dissertation investigates the application of simulations to response history analysis and fling-step characterization. A 3D nonlinear structural model is analyzed using recordings and simulations with similar elastic response spectra. The structural performance and resulting design decisions are similar, indicating that simulations are effective for response history analysis subject to certain conditions. To investigate fling-step, we extract fling pulses from a large set of simulations. Extracted fling properties such as amplitude and period are then compared to specially-processed recordings and relevant empirical models for surface displacement and pulse period. Reasonably good agreement is found between simulations, recordings, and empirical models. In general, ground motion simulations are found to be an effective alternative or supplement to recordings in several engineering applications. Because simulation methods are still developing, this work is not intended as an evaluation of existing methods, but rather as a development of procedures that can be used in ongoing work.

Download or read book Earthquake Processes Physical Modelling Numerical Simulation and Data Analysis Part I written by Mitsuhiro Matsu'ura and published by Birkhäuser. This book was released on 2012-12-06 with total page 389 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the last decade of the 20th century, there has been great progress in the physics of earthquake generation; that is, the introduction of laboratory-based fault constitutive laws as a basic equation governing earthquake rupture, quantitative description of tectonic loading driven by plate motion, and a microscopic approach to study fault zone processes. The fault constitutive law plays the role of an interface between microscopic processes in fault zones and macroscopic processes of a fault system, and the plate motion connects diverse crustal activities with mantle dynamics. An ambitious challenge for us is to develop realistic computer simulation models for the complete earthquake process on the basis of microphysics in fault zones and macro-dynamics in the crust-mantle system. Recent advances in high performance computer technology and numerical simulation methodology are bringing this vision within reach. The book consists of two parts and presents a cross-section of cutting-edge research in the field of computational earthquake physics. Part I includes works on microphysics of rupture and fault constitutive laws, and dynamic rupture, wave propagation and strong ground motion. Part II covers earthquake cycles, crustal deformation, plate dynamics, and seismicity change and its physical interpretation. Topics covered in Part I range from the microscopic simulation and laboratory studies of rock fracture and the underlying mechanism for nucleation and catastrophic failure to the development of theoretical models of frictional behaviors of faults; as well as the simulation studies of dynamic rupture processes and seismic wave propagation in a 3-D heterogeneous medium, to the case studies of strong ground motions from the 1999 Chi-Chi earthquake and seismic hazard estimation for Cascadian subduction zone earthquakes.

Download or read book Ground Motion Simulation Validation for Building Design and Response Assessment written by Peng Zhong and published by . This book was released on 2016 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earthquake ground motion records are used as inputs for seismic hazard analysis, development of ground motion prediction equations and nonlinear response history analysis of structures. Real records from past earthquake events have traditionally been recognized as the best representation of seismic input to these analysis. However, our current way of implementing recorded ground motions is poorly constrained and suffers from the paucity of certain condition ground motions, such as the one with short distance and large magnitude. Meanwhile, even though the scaled ground motion is capable of matching the target spectrum, the content of frequency domain and ground motion parameters become unrealistic. With the rapid growth of computational ability and efficiency of computers, simulated ground motion can be an alternative to provide detailed and accurate prediction of earthquake effect. At the same time, simulated ground motions can provide a better representation of the whole ground motion generation process, such as fault rupture, wave propagation phenomena, and site response characterization. Hence, the aforementioned disadvantage of recorded ground motion can be overcame.Despite ground motion simulations have existed for decades, and the design code, such as ASCE/SEI 7-10 (ASCE, 2010), allow use of simulated ground motions for engineering practice, engineers still worried about the stability in ground motion simulation process and similarity between response of engineered structures to similar simulated and recorded ground motions. In order to draw simulated ground motions into engineering applications and make them practical, this dissertation is making contribution to address this issue. Simulated ground motions have to be validated and compared with recorded ground motions to prove their equivalence in engineering applications.This dissertation proposes a simulation validation framework. First step: Identify ground motion waveform parameters that well correlate with response of Multi-Degree of Freedom (MDOF) buildings and bridges. Second step: Develop goodness-of-fit measures and error functions that can describe the difference between simulated and recorded ground motion waveform characteristics and their effect on MDOF systems. Third step: Device the required update to ground motion simulation methods through which better simulations are possible. Forth step: Assess the current state of simulated ground motions for engineering applications.In general, simulated ground motions are found to be an effective surrogate and replenishment of natural records in engineering applications. However, certain drawbacks are detected, 1) Simulated ground motions are likelihood to mismatch certain ground motion parameters, for example, Arias intensity, duration and so on; 2) Structural behavior resulting from recorded ground motions and simulated ground motions are different. The difference stems from the fact that simulated motions are mostly pulse like motions. Because the simulation methods are still developing, our intent is not ranking or classifying them, but rather to provide feedback to update ground motion simulation techniques such that future simulations are more representative of recorded motions.

Download or read book Sustained Simulation Performance 2014 written by Michael M. Resch and published by Springer. This book was released on 2014-11-26 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the state of the art in high-performance computing and simulation on modern supercomputer architectures. It covers trends in hardware and software development in general and the future of high-performance systems and heterogeneous architectures in particular. The application-related contributions cover computational fluid dynamics, material science, medical applications and climate research; innovative fields such as coupled multi-physics and multi-scale simulations are highlighted. All papers were chosen from presentations given at the 18th Workshop on Sustained Simulation Performance held at the HLRS, University of Stuttgart, Germany in October 2013 and subsequent Workshop of the same name held at Tohoku University in March 2014.

Download or read book Earthquake Ground Motion Simulation and Reliability Implications written by Chiun-Lin Wu and published by . This book was released on 2000 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the purpose of performance evaluation of structures, a phenomenological model is developed for the generation of earthquake ground motions. The simulation procedure is based on the most recent ground motion models and simulation methods. A strong emphasis is placed on uncertaintly modeling and efficiency in application to performance evaluation and reliability analysis. Site locations of special interest include Memphis, TN, Carbondale, IL, St. Louis, MO, and Santa Barbara, CA as they represent U.S. cities in different areas of seismicity.

Download or read book Estimation of the Seismic Response of Buildings and the Effect of Different Scaling Methods for Ground Motion written by Sundar Ram Krishna Murthy Mohan Ram and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Best Practices in Physics based Fault Rupture Models for Seismic Hazard Assessment of Nuclear Installations written by Luis A. Dalguer and published by Birkhäuser. This book was released on 2017-12-20 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume collects several extended articles from the first workshop on Best Practices in Physics-based Fault Rupture Models for Seismic Hazard Assessment of Nuclear Installations (BestPSHANI). Held in 2015, the workshop was organized by the IAEA to disseminate the use of physics-based fault-rupture models for ground motion prediction in seismic hazard assessments (SHA). The book also presents a number of new contributions on topics ranging from the seismological aspects of earthquake cycle simulations for source scaling evaluation, seismic source characterization, source inversion and physics-based ground motion modeling to engineering applications of simulated ground motion for the analysis of seismic response of structures. Further, it includes papers describing current practices for assessing seismic hazard in terms of nuclear safety in low seismicity areas, and proposals for physics-based hazard assessment for critical structures near large earthquakes. The papers validate and verify the models by comparing synthetic results with observed data and empirical models. The book is a valuable resource for scientists, engineers, students and practitioners involved in all aspects of SHA.

Download or read book Stochastic Modeling and Simulation of Near Fault Ground Motions for Performance Based Earthquake Engineering written by Mayssa Dabaghi and published by . This book was released on 2014 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive parameterized stochastic model of near-fault ground motions in two orthogonal horizontal directions is developed. The proposed model uniquely combines several existing and new sub-models to represent major characteristics of recorded near-fault ground motions. These characteristics include near-fault effects of directivity and fling step; temporal and spectral non-stationarity; intensity, duration and frequency content characteristics; directionality of components, as well as the natural variability of motions for a given earthquake and site scenario. By fitting the model to a database of recorded near-fault ground motions with known earthquake source and site characteristics, empirical "observations" of the model parameters are obtained. These observations are used to develop predictive equations for the model parameters in terms of a small number of earthquake source and site characteristics. Functional forms for the predictive equations that are consistent with seismological theory are employed. A site-based simulation procedure that employs the proposed stochastic model and predictive equations is developed to generate synthetic near-fault ground motions at a site. The procedure is formulated in terms of information about the earthquake design scenario that is normally available to a design engineer. Not all near-fault ground motions contain a forward directivity pulse, even when the conditions for such a pulse are favorable. The proposed procedure produces pulselike and non-pulselike motions in the same proportions as they naturally occur among recorded near-fault ground motions for a given design scenario. The proposed models and simulation procedure are validated by several means. Synthetic ground motion time series with fitted parameter values are compared with the corresponding recorded motions. The proposed empirical predictive relations are compared to similar relations available in the literature. The overall simulation procedure is validated by comparing suites of synthetic ground motions generated for given earthquake source and site characteristics to the ground motion prediction equations (GMPEs) developed as part of phase 2 of the Next Generation Attenuation (NGA) program, (NGA-West2, see, e.g., Campbell and Bozorgnia, 2014). Comparison is made in terms of the estimated median level and variability of elastic ground motion response spectra. The use of synthetic motions in addition to or in place of recorded motions is desirable in performance-based earthquake engineering (PBEE) applications, particularly when recorded motions are scarce or when they are unavailable for a specified design scenario. As a demonstrative application, synthetic motions from the proposed simulation procedure are used to perform probabilistic seismic hazard analysis (PSHA) for a near-fault site. The analysis shows that the hazard at a near-fault site is underestimated when the ground motion model used does not properly account for the possibility of pulselike motions due to the directivity effect.

Download or read book New Challenges for Seismic Risk Mitigation in Urban Areas written by Simone Barani and published by Frontiers Media SA. This book was released on 2022-11-30 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Application Of High performance Computing To Earthquake related Problems written by Muneo Hori and published by World Scientific. This book was released on 2024-07-02 with total page 647 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the continued improvements in computing power and digital information availability, we are witnessing the increasing use of high-performance computers to enhance simulations for the forecasting of hazards, disasters, and responses. This major reference work summarizes the theories, analysis methods, and computational results of various earthquake simulations by the use of supercomputers. It covers simulations in the fields of seismology, physical geology, earthquake engineering — specifically the seismic response of structures — and the socioeconomic impact of post-earthquake recovery on cities and societies. Individual chapters address phenomena such as earthquake cycles and plate boundary behavior, tsunamis, structural response to strong ground motion, and post-disaster traffic flow and economic activity. The methods used for these simulations include finite element methods, discrete element methods, smoothed particle hydrodynamics, and multi-agent models, among others.The simulations included in this book provide an effective bird's-eye view of cutting-edge simulations enhanced with high-performance computing for earthquake occurrence, earthquake damage, and recovery from the damage, combining three of the major fields of earthquake studies: earth science, earthquake engineering, and disaster-mitigation-related social science. The book is suitable for advanced undergraduates, graduates, and researchers in these fields.

Download or read book Stochastic Model for Earthquake Ground Motion Using Wavelet Packets written by Yoshifumi Yamamoto and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: For performance-based design, nonlinear dynamic structural analysis for various types of input ground motions is required. Stochastic (simulated) ground motions are sometimes useful as input motions, because unlike recorded motions they are not limited in number and because their properties can be varied systematically to study the impact of ground motion properties on structural response. This dissertation describes an approach by which the wavelet packet transform can be used to characterize complex time-varying earthquake ground motions, and it illustrates the potential benefits of such an approach in a variety of earthquake engineering applications. The proposed model is based on Thráinsson and Kiremidjian (2002), which use Fourier amplitudes and phase differences to simulate ground motions and attenuation models to their model parameters. We extend their model using wavelet packet transform since it can control the time and frequency characteristic of time series. The time- and frequency-varying properties of real ground motions can be captured using wavelet packets, so a model is developed that requires only 13 parameters to describe a given ground motion. These 13 parameters are then related to seismological variables such as earthquake magnitude, distance, and site condition, through regression analysis that captures trends in mean values, standard deviations and correlations of these parameters observed in a large database of recorded strong ground motions. The resulting regression equations then form a model that can be used to predict ground motions for a future earthquake scenario; this model is analogous to widely used empirical ground motion prediction models (formerly called "attenuation models") except that this model predicts entire time series rather than only response spectra. The ground motions produced using this predictive model are explored in detail, and are shown to have elastic response spectra, inelastic response spectra, durations, mean periods, etc., that are consistent in both mean and variability to existing published predictive models for those properties. That consistency allows the proposed model to be used in place of existing models for probabilistic seismic hazard analysis (PSHA) calculations. This new way to calculate PSHA is termed "simulation-based probabilistic seismic hazard analysis" and it allows a deeper understanding of ground motion hazard and hazard deaggregation than is possible with traditional PSHA because it produces a suite of potential ground motion time histories rather than simply a distribution of response spectra. The potential benefits of this approach are demonstrated and explored in detail. Taking this analysis even further, this suite of time histories can be used as input for nonlinear dynamic analysis of structures, to perform a risk analysis (i.e., "probabilistic seismic demand analysis") that allows computation of the probability of the structure exceeding some level of response in a future earthquake. These risk calculations are often performed today using small sets of scaled recorded ground motions, but that approach requires a variety of assumptions regarding important properties of ground motions, the impacts of ground motion scaling, etc. The approach proposed here facilitates examination of those assumptions, and provides a variety of other relevant information not obtainable by that traditional approach.