Download or read book Site Characterization for Probabilistic Ground Shock Predictions written by John Guy Jackson and published by . This book was released on 1982 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Site Characterization for Probabilistic Ground Shock Predictions written by J. G Jackson (Jr) and published by . This book was released on 1982 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: A probabilistic methodology is described for determining the statistical distribution of vertical rattlespace required for MX multiple protective shelters sited within the alluvial valleys of central Nevada and eastern Utah. The approach involves (a) identifying the critical ground motion parameters and the input quantities which dominate their calculation, (b) conducting field and laboratory investigations to define the statistical variation of these quantities within the siting area, and (c) performing ground motion calculations with a probabilistic wave propagation code. Calculations for the high-explosive Dynamic In-Situ Compressibility (DISC) tests conducted in Ralston Valley, Nevada, are used to illustrate the probabilistic methodology.

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 Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 994 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Long range Science and Technology Plan Combat support written by and published by . This book was released on 1985 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technical Abstract Bulletin written by and published by . This book was released on with total page 908 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Probabilistic One dimensional Ground shock Code for Layered Nonlinear Hysteretic Material written by Behzad Rohani and published by . This book was released on 1984 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Probabilistic Assessments of the Seismic Stability of Slopes written by Yubing Wang and published by . This book was released on 2014 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earthquake-induced landslides are a significant seismic hazard that can generate large economic losses. Predicting earthquake-induced landslides often involves an assessment of the expected sliding displacement induced by the ground shaking. A deterministic approach is commonly used for this purpose. This approach predicts sliding displacements using the expected ground shaking and the best-estimate slope properties (i.e., soil shear strengths, ground water conditions and thicknesses of sliding blocks), and does not consider the aleatory variability in predictions of ground shaking or sliding displacements or the epistemic uncertainties in the slope properties. In this dissertation, a probabilistic framework for predicting the sliding displacement of flexible sliding masses during earthquakes is developed. This framework computes a displacement hazard curve using: (1) a ground motion hazard curve from a probabilistic seismic hazard analysis, (2) a model for predicting the dynamic response of the sliding mass, (3) a model for predicting the sliding response of the sliding mass, and (4) a logic tree that incorporates the uncertainties in the various input parameters. The developed probabilistic framework for flexible sliding masses is applied to a slope at a site in California. The results of this analysis show that the displacements predicted by the probabilistic approach are larger than the deterministic approach due to the influence of the uncertainties in the slope properties. Reducing these uncertainties can reduce the predicted displacements. Regional maps of seismic landslide potential are used in land-use planning and to identify zones that require detailed, site-specific studies. Current seismic landslide hazard mapping efforts typically utilize deterministic approaches to estimate rigid sliding block displacements and identify potential slope failures. A probabilistic framework that uses displacement hazard curves and logic-tree analysis is developed for regional seismic landslide mapping efforts. A computationally efficient approach is developed that allows the logic-tree approach to be applied for regional analysis. Anchorage, Alaska is used as a study area to apply the developed approach. With aleatory variability and epistemic uncertainties considered, the probabilistic map shows that the area of high/very high hazard of seismic landslides increases by a factor of 3 compared with a deterministic map.

Download or read book An Objective Waveform Comparison Technique written by George Y. Baladi and published by . This book was released on 1983 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report documents the development of objective waveform discrepancy measures for comparing arbitrary transient response histories. The objective waveform discrepancy measures consist of the magnitude correlation factor, the phase-and-frequency correlation factor, the magnitude error, the phase-and-frequency error, and the combined magnitude and phase-and-frequency errors. Their validity and behavior are checked and demonstrated for several simple sinusoidal responses. The objective discrepancy measures are incorporated into a computer program, named Waveforms Comparison Technique, which processed digitized data tapes containing measured or calculated waveforms or both. The computer program is used to statistically analyze selected data from the DISC Test I event and objectively compare particle velocity measurements made in DISC Test II with expected value waveforms obtained from probabilistic prediction calculations. Appendix A of this report presents a flow chart and user's guide for the computer program WCT. It is recommended that the objective discrepancy measures be used whenever comparisons of two or more waveforms are made. It is also recommended that the technique be extended to objectively quantify differences in laboratory-and field-generated material property test results. (Author).

Download or read book List of Publications of the U S Army Engineer Waterways Experiment Station written by U.S. Army Engineer Waterways Experiment Station and published by . This book was released on 1993 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 1 D Probabilistic Ground Shock Analysis of Generic Mountain C written by James B. Wilson and published by . This book was released on 1992 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Site Characterization Progress Report written by and published by . This book was released on 1996 with total page 662 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ground Motion Intensity Measures for Seismic Probabilistic Risk Analysis written by Marco De Biasio and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A fundamental issue that arises in the framework of Probabilistic Seismic Risk Analysis is the choice of groundmotion Intensity Measures (IMs). In addition to reducing record-to-record variability, an improved IM (i.e. one able tobetter capture the damaging features of a record, as well as the site hazard) provides criteria for selecting input groundmotions to loosen restrictions.Two new structure-specific IMs are proposed in this study: the first, namely ASAR (i.e. Relative Average SpectralAcceleration), is conceived for Structural demand prediction, the second namely, E-ASAR (i.e. Equipment-RelativeAverage Spectral Acceleration), aims to predict Non-Structural components acceleration demand. The performance ofthe proposed IMs are compared with the ones of current IMs, based on: a) a large dataset of thousands recordedearthquake ground motions; b) numerical analyses conducted with state-of-the-art FE models, representing actualload-bearing walls and frame structures, and validated against experimental tests; and c) systematic statistical analysesof the results. According to the comparative study, the introduced IMs prove to be considerably more “efficient” withrespect to the IMs currently used. Likewise, both ASAR and E-ASAR have shown to own the characteristic of“sufficiency” with respect to magnitude, source-to-site distance and soil-type (Vs30). Furthermore, both the introducedIMs possess the valuable characteristics to need (in order to be computed) merely the knowledge of the building'sfundamental frequency, exactly as it is for the wide-spread spectral acceleration Spa(f1). This key characteristic makesboth ASAR and E-ASAR easily exploitable in Probabilistic Seismic Hazard Analysis.Therefore, due to their proven efficiency, sufficiency, robustness and applicable formulation, both ASAR and EASARcan be considered as worthy candidates for defining seismic hazard within the frameworks of both Probabilisticand Deterministic Seismic Risk Analysis.

Download or read book Proceedings of the Sixth International Symposium on Interaction of Nonnuclear Munitions with Structures Panama City Beach Florida May 3 7 1993 written by and published by . This book was released on 1993 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Earthquake Research and Analysis written by Sebastiano D'Amico and published by IntechOpen. This book was released on 2012-01-27 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of earthquakes combines science, technology and expertise in infrastructure and engineering in an effort to minimize human and material losses when their occurrence is inevitable. This book is devoted to various aspects of earthquake research and analysis, from theoretical advances to practical applications. Different sections are dedicated to ground motion studies and seismic site characterization, with regard to mitigation of the risk from earthquake and ensuring the safety of the buildings under earthquake loading. The ultimate goal of the book is to encourage discussions and future research to improve hazard assessments, dissemination of earthquake engineering data and, ultimately, the seismic provisions of building codes.

Download or read book Some Considerations in the Analysis and Prediction of Ground Shock from Buried Conventional Explosions written by Cornelius J. Higgins and published by . This book was released on 1983 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper discusses several topics associated with the analysis and prediction of ground shock from buried conventional explosions. The paper is not intended to provide detailed equations for ground shock predictions. Other papers in this conference provide such information. Rather, this paper is intended to address topics associated with general methodology and uncertainty. As a background for discussion, the first part of the paper lists and briefly discusses the major parameters which govern the ground shock. Some of the parameters are treated in more detail in later sections of the paper. The second and main part of the paper treats scaling. It attempts to put the usefulness of dimensional analysis, scaling the theoretical calculations in perspective. The third portion of the paper discusses the characteristics of a limited data set with respect to material properties and depth of burst factors. Some brief comments about soil-structure interactions and loads on structures are made in a fourth part. Finally, research needs to enable improvement in conventional ground shock and soil-structure interaction technology are mentioned. (Author).

Download or read book Energy Research Abstracts written by and published by . This book was released on 1993 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt: