Tesi: "Earthquake"

7

Cothern, Keegan. "Bracing Japan: Earthquakes, Nature, Planning, and the (Re)Construction of Japan, 1923-1995." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1462783823.

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8

Convers, Jaime Andres. "Global investigations of radiated seismic energy and real-time implementation." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50356.

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This dissertation contains investigations of radiated seismic energy measurements from large earthquakes and duration determinations as significant properties of the dynamic earthquake rupture and its applications in the identification of very large and slow source rupturing earthquakes. This includes a description of earthquake released seismic energy from 1997 to 2010 and identification of slow source tsunami earthquakes in that time period. The implementation of these measurements in real-time since the beginning of 2009, with a case study of the Mentawai 2010 tsunami earthquake are also discussed. Further studies of rupture duration assessments and its technical improvements for more rapid and robust solutions are investigated as well, with application to the Tohoku-Oki 2011 earthquake an a case of directivity in the 2007 Mw 8.1 Solomon islands earthquake. Finally, the set of routines and programs developed for implementation at Georgia Tech and IRIS to produce the real-time results since 2009 presented in this study are described.

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9

Kumar, Senthil. "Earthquake size, recurrence and rupture mechanics of large surface-rupture earthquakes along the Himalayan Frontal Thrust of India /." abstract and full text PDF (free order & download UNR users only), 2005. http://0-wwwlib.umi.com.innopac.library.unr.edu/dissertations/fullcit/3209126.

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Thesis (Ph. D.)--University of Nevada, Reno, 2005. "August 2005." Includes bibliographical references. Online version available on the World Wide Web. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2005]. 1 microfilm reel ; 35 mm.

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10

Petal, Marla Ann. "Urban disaster mitigation and preparedness the 1999 Kocaeli earthquake /." online access from Digital Dissertation Consortium access full-text, 2004. http://libweb.cityu.edu.hk/cgi-bin/er/db/ddcdiss.pl?3142562.

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11

Carlton, Aerik. "Performance-based engineering framework for earthquake and fire following earthquake." Thesis, Michigan Technological University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1552728.

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The objective for this thesis is to outline a Performance-Based Engineering (PBE) framework to address the multiple hazards of Earthquake (EQ) and subsequent Fire Following Earthquake (FFE). Currently, fire codes for the United States are largely empirical and prescriptive in nature. The reliance on prescriptive requirements makes quantifying sustained damage due to fire difficult. Additionally, the empirical standards have resulted from individual member or individual assembly furnace testing, which have been shown to differ greatly from full structural system behavior. The very nature of fire behavior (ignition, growth, suppression, and spread) is fundamentally difficult to quantify due to the inherent randomness present in each stage of fire development. The study of interactions between earthquake damage and fire behavior is also in its infancy with essentially no available empirical testing results. This thesis will present a literature review, a discussion, and critique of the state-of-the-art, and a summary of software currently being used to estimate loss due to EQ and FFE. A generalized PBE framework for EQ and subsequent FFE is presented along with a combined hazard probability to performance objective matrix and a table of variables necessary to fully implement the proposed framework. Future research requirements and summary are also provided with discussions of the difficulties inherent in adequately describing the multiple hazards of EQ and FFE.

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12

Prante, Mitchell R. "Earthquake Petrology: Linking Fault-Related Deformation to the Earthquake Cycle." DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/2039.

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Faults have a controlling influence on a variety of geologic processes includingfluid flow, the mechanical behavior of the crust, and seismicity. The geologic sciences have long recognized that faults generate earthquakes; however, few indicators of ancient earthquakes exist in fault-zones. This dissertation documents several indicators for the preservation of ancient earthquakes in fault-zones including frictional melt (pseudotachylyte), highly-polished fault slip surfaces, and hydrothermal alteration. These deformation products result from rapid generation of frictional heat during earthquakes.This dissertation also focuses on the seismic potential of continental low-angle normal faults (LANF). We document the preservation of voluminous pseudotachylyte along a LANF suggesting that the fault repeatedly nucleated large earthquakes. Additionally, a synthesis of reported occurrences of LANF pseudotachylyte indicates that LANF seismicity is common during extension. This has important implication for the mechanics and evolution of LANFs and for the assessment of seismic hazards.We also present a little used, high resolution, and low-cost 3D range camera for use in geolgy. The KinectTM is a 3D infrared range camera that can be used to collect high- resolution (± 1 mm), 3D data in both field and laboratory settings. We describe the use of the KinectTM in geologic appications and recommend more widespread use.

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13

Kiser, Eric. "Earthquake Characteristics as Imaged by the Back-Projection Method." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10355.

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This dissertation explores the capability of dense seismic array data for imaging the rupture properties of earthquake sources using a method known as back-projection. Only within the past 10 or 15 years has implementation of the method become feasible through the development of large aperture seismic arrays such as the High Sensitivity Seismograph Network in Japan and the Transportable Array in the United States. Coincidentally, this buildup in data coverage has also been accompanied by a global cluster of giant earthquakes (Mw>8.0). Much of the material in this thesis is devoted to imaging the source complexity of these large events. In particular, evidence for rupture segmentation, dynamic triggering, and frequency dependent energy release is presented. These observations have substantial implications for evaluating the seismic and tsunami hazards of future large earthquakes. In many cases, the details of the large ruptures can only be imaged by the back-projection method through the addition of different data sets and incorporating additional processing steps that enhance low-amplitude signals. These improvements to resolution can also be utilized to study much smaller events. This approach is taken for studying two very different types of earthquakes. First, a global study of the enigmatic intermediate-depth (100-300 km) earthquakes is performed. The results show that these events commonly have sub-horizontal rupture planes and suggest dynamic triggering of multiple sub-events. From these observations, a hypothesis for the generation of intermediate-depth events is proposed. Second, the early aftershock sequences of the 2004 Mw 9.1 Sumatra-Andaman and 2011 Mw 9.0 Tohoku, Japan earthquakes are studied using the back-projection method. These analyses show that many events can be detected that are not in any local or global earthquake catalogues. In particular, the locations of aftershocks in the back-projection results of the 2011 Tohoku sequence fill in gaps in the aftershock distribution of the Japan Meteorological Agency catalogue. These results may change inferences of the behavior of the 2011 mainshock, as well as the nature of future seismicity in this region. In addition, the rupture areas of the largest aftershocks can be determined, and compared to the rupture area of the mainshock. For the Tohoku event, this comparison reveals that the aftershocks contribute significantly to the cumulative failure area of the subduction interface. This result implies that future megathrust events in this region can have larger magnitudes than the 2011 event. Earth and Planetary Sciences

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14

Wu, Xin. "Defying Disaster: Earthquake." Digital WPI, 2015. https://digitalcommons.wpi.edu/etd-theses/1188.

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The tremendous growth in the serious games market presents the opportunity to help people learn through playing games. Defying Disaster is a 2D side scroller serious game designed to teach people how to prepare for and handle an earthquake. Players do a series of mini games that provide earthquake survival tips while interacting with a larger world after an earthquake disaster. An evaluation with thirty people compared learning disaster knowledge through reading materials versus playing games. The results show people learn better through playing Defying Disaster than reading materials.

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15

Chen, Yingying. "Defying Disaster: Earthquake." Digital WPI, 2015. https://digitalcommons.wpi.edu/etd-theses/1189.

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The tremendous growth in the serious games market presents the opportunity to help people learn through playing games. Defying Disaster is a 2D side scroller serious game designed to teach people how to prepare for and handle an earthquake. Players do a series of mini games that provide earthquake survival tips while interacting with a larger world after an earthquake disaster. An evaluation with thirty people compared learning disaster knowledge through reading materials versus playing games. The results show people learn better through playing Defying Disaster than reading materials.

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16

Budimir, Mirianna. "Cascading natural hazards : probability and loss modelling for earthquakes and earthquake-triggered landslides." Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/378652/.

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17

Wu, Jie Ying. "A comparative study of housing reconstruction after two major earthquakes the 1994 Northridge earthquake in the United States and the 1999 Chi-Chi earthquake in Taiwan /." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969/74.

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18

Schwartz, Richard Jay. "Analysis of prehistoric shoreline structures of Coastal South Carolina and their significance in assessing regional geological stability." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/25804.

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19

Evans, Lisa. "Cyclic group and knapsack facets with applications to cutting planes." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/30639.

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20

Marc, Odin [Verfasser], and Niels [Akademischer Betreuer] Hovius. "Earthquake-induced landsliding : earthquakes as erosional agents across timescales / Odin Marc ; Betreuer: Niels Hovius." Potsdam : Universität Potsdam, 2016. http://d-nb.info/1218400951/34.

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21

Bäckman, Erik. "Defining an Earthquake Intensity Based Method for a Rapid Earthquake Classification System." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-317406.

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Ground motions caused by earthquakes may be strong enough to cause destruction of infrastructure and possibly casualties. If such past destructive earthquakes are analysed, the gained information could be used to develop earthquake warning systems that predicts and possibly reduce the damage potential of further earthquakes. The Swedish National Seismic Network (SNSN) runs an automated early warning system that attempts to predict the damage of an earthquake that just got recorded, and forward the predictions to relevant government agencies. The predictions are based on, e.g. earthquake magnitude, source depth and an estimate of the size of affected human population. The purpose of this thesis is to introduce an additional parameter: earthquake intensity, which is a measure of the intensity with which the ground shakes. Based on this, a new earthquake hazard scheme, the Intensity Based Earthquake Classification (IBEC) scheme, is created. This scheme suggests alternate methods, relative to SNSN, of how earthquake classifications can be made. These methods will use an intensity database established by modelling scenario earthquakes in the open-source software ShakeMap by the U.S. Geological Survey. The database consists of scenarios on the intervals: 4.0 ≤ Mw ≤ 9.0 and 10 ≤ depth ≤ 150 kilometre, and covers the whole intensity scale, Modified Mercalli Intensity, 1.0 ≤ Imm ≤ 10.0. The IBEC classification scheme also enabled the creation of the 'Population-to-Area' criterion. It improves prediction of earthquakes that struck isolated cities, located in e.g. valleys in large mountainous areas and deserts. Even though such earthquakes are relatively uncommon, once they occur, they may cause great damage as many cities in such regions around the world often are less developed regarding resistance to ground motions. Markrörelser orsakade av jordbävningar kan va starka nog att skada vår infrastruktur och orsaka dödsoffer. Genom att analysera forna destruktiva jordbävningar och utveckla program som försöker att förutsäga deras inverkan så kan den potentiella skada minskas. Svenska Nationella Seismiska Nätet (SNSN) driver ett automatiserat tidigt varningssystem som försöker förutsäga skadorna som följer en jordbävning som precis spelats in, och vidarebefodra denna information till relevanta myndigheter. Förutsägelserna är baserade på, t.ex. jordbävnings-magnitud och djup samt uppskattning av mänsklig population i det påverkade området. Syftet med denna avhandlingen är att introducera ytterligare en parameter: jordbävnings-intensitet, som är ett mått av intensiteten i markrörelserna. Baserat på detta skapas ett jordbävnings-schema kallat Intensity Based Earthquake Classification (IBEC). Detta schema föreslår alternativa metoder, relativt SNSN, för hur jordbävnings-klassificering kan göras. Dessa metoder använder sig av en intensitets-databas etablerad genom modellering av jordbävning-scenarios i open source-\linebreak programmet ShakeMap, skapat av U.S. Geological Survey. Databasen består av scenarior över intervallen 4.0 ≤ Mw ≤ 9.0 och 10 ≤ djup ≤ 150 kilometer, vilka täcker hela intensitetsskalan, Modified Mercalli Intensity, 1.0 ≤ Imm ≤ 10.0. IBECs klassificeringsschema har även möjliggjort skapandet av "Population-mot-Area"-kriteriet. Detta förbättrar förutsägelsen av jordbävningar som träffar isolerade städer, placerade i t.ex. dalgångar i stora bergskjedjor och öknar. Även om denna typ av jordbävningar är relativt ovanliga så orsakar dom ofta enorm skada då sådana här städer ofta är mindre utvecklade rörande byggnaders motstånd mot markrörelser.

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22

Neupane, Ganesh Prasad. "Comparison of Natural and Predicted Earthquake Occurrence in Seismologically Active Areas for Determination of Statistical Significance." Bowling Green, Ohio : Bowling Green State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1213494761.

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23

Salman, Firas, and Mouhammed Hussain. "Earthquake Resistant Wooden House." Thesis, Linnaeus University, School of Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-5908.

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Wood-stud shear walls are commonly used to provide lateral stability against horizontal forces in wood houses. Therefore, accurate predictions of the deformation properties of shear walls are necessary in order to improve the design of wood frame houses against earthquake loading. The aim of this thesis is to increase damping capacity of wood-stud shear walls and hence improve wood frame houses resistance against earthquake.The starting point has been the laboratory experiments of nail joint’s deformation properties. Purpose of the experiments was to determine material properties of a nail joint. The material properties have later been used as material input data in the finite element (FE) model of wood-stud shear wall elements under alternating lateral loading. FE results have shown that wood-stud shear wall element’s damping capacity is mainly dependent on nail joints properties, number of nail joints, wall dimension and the use of middle studs. Skjuvväggar av trä används ofta för att ge stabilitet åt horisontalbelastade träshustommar. Därför är kunskaper om skjuvväggars deformationsegenskaper nödvändiga för att kunna förbättra utformningen av trästommar utsatta för jordbävningslaster. Syftet med detta examenarbete är att visa på olika sätt som ökar skjuvväggars absorberande energi eller dämpningskapacitet och som därigenom ger möjligheter att förbättra trästommars motstånd mot jordbävningslaster. Utgångspunkten har varit laboratorieexperimenten avseende spikförbandens deformationsegenskaper. Syftet med experimenten var att bestämma materialegenskaper för två olika spikförband. Materialsambanden användes därefter som indata i finita element (FE) modeller av skjuvväggselement utsatta för växlande sidobelastning. FE resultaten har visat att skjuvväggars totala dämpningskapacitet beror i huvudsak på spikförbandets materialegenskaper, antal spikförband, väggdimensionen och användningen av mellanreglar.

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24

Hainzl, Sebastian, Frank Scherbaum, and Gert Zöller. "Spatiotemporal earthquake patterns : [Poster]." Universität Potsdam, 2006. http://www.uni-potsdam.de/imaf/events/ge_work0602.html.

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25

Hainzl, Sebastian. "Earthquake triggering and interaction." Thesis, Universität Potsdam, 2011. http://opus.kobv.de/ubp/volltexte/2011/5009/.

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Earthquake faults interact with each other in many different ways and hence earthquakes cannot be treated as individual independent events. Although earthquake interactions generally lead to a complex evolution of the crustal stress field, it does not necessarily mean that the earthquake occurrence becomes random and completely unpredictable. In particular, the interplay between earthquakes can rather explain the occurrence of pronounced characteristics such as periods of accelerated and depressed seismicity (seismic quiescence) as well as spatiotemporal earthquake clustering (swarms and aftershock sequences). Ignoring the time-dependence of the process by looking at time-averaged values – as largely done in standard procedures of seismic hazard assessment – can thus lead to erroneous estimations not only of the activity level of future earthquakes but also of their spatial distribution. Therefore, it exists an urgent need for applicable time-dependent models. In my work, I aimed at better understanding and characterization of the earthquake interactions in order to improve seismic hazard estimations. For this purpose, I studied seismicity patterns on spatial scales ranging from hydraulic fracture experiments (meter to kilometer) to fault system size (hundreds of kilometers), while the temporal scale of interest varied from the immediate aftershock activity (minutes to months) to seismic cycles (tens to thousands of years). My studies revealed a number of new characteristics of fluid-induced and stress-triggered earthquake clustering as well as precursory phenomena in earthquake cycles. Data analysis of earthquake and deformation data were accompanied by statistical and physics-based model simulations which allow a better understanding of the role of structural heterogeneities, stress changes, afterslip and fluid flow. Finally, new strategies and methods have been developed and tested which help to improve seismic hazard estimations by taking the time-dependence of the earthquake process appropriately into account. Erdbeben interagieren in vielfältiger Weise miteinander, weshalb sie nicht als einzelne, unabhängige Ereignisse behandelt werden können. Obwohl diese Erdbebenwechselwirkungen in der Regel zu einer komplexen Entwicklung des Spannungsfelds führen, bedeutet dies nicht zwangsläufig, dass Erdbeben rein zufällig und völlig unberechenbar auftreten. Insbesondere kann das Zusammenspiel zwischen Erdbeben zu ausgeprägten Charakteristiken wie Phasen beschleunigter Aktivität, seismischer Ruhe sowie raumzeitlichen Erdbebenanhäufungen (Schwärme und Nachbebensequenzen) führen. Die Vernachlässigung der Zeitabhängigkeit des Erdbebenprozesses kann somit zu fehlerhaften Einschätzungen nicht nur des zukünftigen Aktivitätsniveaus, sondern auch der räumlichen Verteilung führen. Daher besteht ein dringender Bedarf an geeigneten zeitabhängigen Seismizitätsmodellen. Meine Arbeit zielt auf ein verbessertes Verständnis und Charakterisierung der Interaktionen von Erdbeben ab, um Abschätzungen der Erdbebengefährdung zu verbessern. Zu diesem Zweck untersuche ich Seismizitätsmuster auf den räumlichen Skalen von hydraulisch induzierten Öffnungsbrüchen (Meter bis Kilometer) bis zu Verwerfungssystemen (Hunderte von Kilometern), während die zeitlichen Skalen von Nachbebenaktivität (Minuten bis Monate) bis zu seismischen Zyklen (bis zu mehrere tausendend Jahre) reichen. Meine Studien ergeben eine Reihe neuer Merkmale von Fluid- und Spannungs-induzierten Erdbeben. Ergänzend zur reinen Datenanalyse der Erdbeben- und Deformationsdaten liefern statistische und Physik-basierte Modellsimulationen ein besseres Verständnis der Rolle von strukturellen Heterogenitäten, Spannungsänderungen und postseismischen Prozessen. Schließlich konnten neue Strategien und Methoden entwickelt und getestet werden, mit denen die Erdbebengefährdung besser eingeschätzt werden kann, indem die Zeitabhängigkeit des Erdbebens Prozess angemessen berücksichtigt wird.

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26

Dørheim, Helge. "Methods for Earthquake Analysis." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for konstruksjonsteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18472.

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Based on the need for effective solutions of structures response to seismic loading, this thesis includes the theoretical background, and explanation of several methods. There are many theories in the community, but the ones chosen to be looked closer at here are Modal response spectrum analysis for symmetric and asymmetric plan structures, Modal Pushover Analysis for symmetric and asymmetric plan structures and Linear and Non-Linear Response History Analysis. The theory has been adapted from published papers and books on the topic.The report is divided into three main sections, numerical methods for solving of dynamic problems, elastic analysis and inelastic analysis. The chapters on Elastic and Inelastic analysis are further divided into sections on symmetric and asymmetric plan.Elastic analyses by hand calculations and SAP2000 have been performed on a 2D-frame, aSAP2000 Elastic Response spectrum analysis has been performed on a 3D-frame, and aninelastic modal pushover analysis in SAP2000 has been performed on a 2D frame.The target for this inquiry is to discover advantages and disadvantages in the different methods and comparing them.

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27

Lopez, Ibaceta Alvaro Francisco. "Seismic Performance of Substandard Reinforced Concrete Bridge Columns under Subduction-Zone Ground Motions." PDXScholar, 2019. https://pdxscholar.library.pdx.edu/open_access_etds/4977.

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A large magnitude, long duration subduction earthquake is impending in the Pacific Northwest, which lies near the Cascadia Subduction Zone (CSZ). Great subduction zone earthquakes are the largest earthquakes in the world and are the sole source zones that can produce earthquakes greater than M8.5. Additionally, the increased duration of a CSZ earthquake may result in more structural damage than expected. Given such seismic hazard, the assessment of reinforced concrete substructures has become crucial in order to prioritize the bridges that may need to be retrofitted and to maintain the highway network operable after a major seismic event. Recent long duration subduction earthquakes occurred in Maule, Chile (Mw 8.8, 2010) and Tohoku, Japan (Mw 9.0, 2011) are a reminder of the importance of studying the effect of subduction ground motions on structural performance. For this purpose, the seismic performance of substandard circular reinforced concrete bridge columns was experimentally evaluated using shake table tests by comparing the column response from crustal and subduction ground motions. Three continuous reinforced columns and three lap-spliced columns were tested using records from 1989 Loma Prieta, 2010 Maule and 2011 Tohoku. The results of the large-scale experiments and numerical studies demonstrated that the increased duration of subduction ground motions affects the displacement capacity and can influence the failure mode of bridge columns. Furthermore, more damage was recorded under the subduction ground motions as compared to similar maximum deformations under the crustal ground motion. The larger number of plastic strain cycles imposed by subduction ground motions influence occurrence of reinforcement bar buckling at lower displacement compared to crustal ground motions. Moreover, based on the experimental and numerical results, subduction zone ground motion effects are considered to have a significant effect on the performance of bridge columns. Therefore, it is recommended to consider the effects of subduction zone earthquakes in the performance assessment of substandard bridges, or when choosing ground motions for nonlinear time-history analysis, especially in regions prone to subduction zone mega earthquakes. Finally, for substandard bridges not yet retrofitted or upgraded seismically, the following performance limit recommendation is proposed: for the damage state of collapse, which is related to the ODOT's Life Safety performance level, the maximum strain in the longitudinal reinforcement should be reduced from 0.09 (in./in.) to a value of 0.032 (in./in.) for locations where subduction zone earthquakes are expected, to take into consideration the occurrence of bar buckling.

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Johansson, Stefan. "Earthquake Analysis Using a Migration Based Detection Algorithm Applied to Local Earthquake Data." Thesis, Uppsala universitet, Geofysik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-325373.

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In this study earthquake data is analyzed using a newly developed Migration Based Detection (MBD) algorithm (Wagner et al. 2017). A software environment suitable for manual analysis of large quantities of earthquakes (events) detected by the MBD algorithm is set up, and the MBD algorithm is applied to 13 days of seismic data from a network of 26 seismic stations in the geologically complex Hengill-area in southwest Iceland. A total of 859 event detections are produced and manually inspected. Out of these, 483 are considered true and/or uncertain, making the assessed number of false detections about 44%. A subset of 53 well defined true events are selected for event relocation using manual picking of first arrival P-waves. The relocation resulted in a mean difference of roughly 0.6 km for each coordinate in the horizontal plane and about 1.4 km in depth. Results of the study provide reference data that may aid further development of the MBD algorithm, as well as provide some insight into the performance of the MBD algorithm. The software environment tailored for analyzing events detected by the MBD algorithm may be used as a foundation for continued analysis of detected events. I denna studie analyserades jordskalvsdata med hjälp av en nyligen utvecklad 'migration based detection'-algoritm (Wagner et al. 2017). En mjukvarumiljö skräddarsydd för manuell analys av stora kvantiteter av jordskalv detekterade av MBD-algoritmen iordningställdes, varpå MBD-algoritmen sedan applicerades på 13 dagar av seismisk data från ett nätverk av 26 seismiska stationer i det geologiskt sett komplexa Hengill-området i sydvästra Island. Totalt detekterades 859 jordskalv som genomgick manuell analys. Av dessa klassificerades 483 stycken som bekräftade eller troliga jordskalv, vilket resulterar i en uppskattad felmarginal om ca. 44 %. En delmängd om 53 väldefinierade jordskalv valdes ut för noggrannare analys av ursprungsplats och tidpunkt genom manuell plockning av P-fasankomst. Omlokaliseringen resulterade i en genomsnittlig differens om ca. 0.6 km i vardera koordinat i horisontalplanet och ca. 1.4 km i höjdled. Resultat från projektet kan användas som referensdata vid vidareutveckling av MBD-algoritmen samt ger viss insyn i prestandan hos MBD-algoritmen. Den iordningställda datormiljön kan användas som bas för vidare analys av jordskalv detekterade av MBD-algoritmen.

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29

Durmaz, Sıdıka Bahar Serim Erkal. "Earthquake conscious urban transformation and redevelopment:repercussions of İzmir radius project on Fikri Altay district/." [s.l.]: [s.n.], 2005. http://library.iyte.edu.tr/tezler/master/sehirplanlama/T000378.pdf.

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Thesis (Master)--İzmir Institute of Technology, İzmir, 2005. Keywords: Earthquake risk, damage estimation, risk assessment, earthquake resistance, urban renewal. Includes bibliographical references (leaves. 138-143).

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30

McHattie, Samuel Alexander. "Seismic Response of the UC Physics Building in the Canterbury Earthquakes." Thesis, University of Canterbury. Civil and Natural Resource Engineering, 2013. http://hdl.handle.net/10092/8801.

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The purpose of this thesis is to evaluate the seismic response of the UC Physics Building based on recorded ground motions during the Canterbury earthquakes, and to use the recorded response to evaluate the efficacy of various conventional structural analysis modelling assumptions. The recorded instrument data is examined and analysed to determine how the UC Physics Building performed during the earthquake-induced ground motions. Ten of the largest earthquake events from the 2010-11 Canterbury earthquake sequence are selected in order to understand the seismic response under various levels of demand. Peak response amplitude values are found which characterise the demand from each event. Spectral analysis techniques are utilised to find the natural periods of the structure in each orthogonal direction. Significant torsional and rocking responses are also identified from the recorded ground motions. In addition, the observed building response is used to scrutinise the adequacy of NZ design code prescriptions for fundamental period, response spectra, floor acceleration and effective member stiffness. The efficacy of conventional numerical modelling assumptions for representing the UC Physics Building are examined using the observed building response. The numerical models comprise of the following: a one dimensional multi degree of freedom model, a two dimensional model along each axis of the building and a three dimensional model. Both moderate and strong ground motion records are used to examine the response and subsequently clarify the importance of linear and non-linear responses and the inclusion of base flexibility. The effects of soil-structure interaction are found to be significant in the transverse direction but not the longitudinal direction. Non-linear models predict minor in-elastic behaviour in both directions during the 4 September 2010 Mw 7.1 Darfield earthquake. The observed torsional response is found to be accurately captured by the three dimensional model by considering the interaction between the UC Physics Building and the adjacent structure. With the inclusion of adequate numerical modelling assumptions, the structural response is able to be predicted to within 10% for the majority of the earthquake events considered.

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31

Mak, Sum. "Seismic analysis of the South China Region." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B30588893.

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32

Teakle, Geraldine Mary Reid. "Incentives for earthquake hazard mitigation /." Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09ENV/09envt253.pdf.

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33

Wu, Chunquan. "Fault zone damage, nonlinear site response, and dynamic triggering associated with seismic waves." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41143.

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My dissertation focuses primarily on the following three aspects associated with passing seismic waves in the field of earthquake seismology: temporal changes of fault zone properties, nonlinear site response, and dynamic triggering. Quantifying the temporal changes of material properties within and around active fault zones (FZ) is important for better understanding of rock rheology and estimating the strong ground motion that can be generated by large earthquakes. As high-amplitude seismic waves propagate through damaged FZ rocks and/or shallow surface layers, they may produce additional damage leading to nonlinear wave propagation effects and temporal changes of material properties (e.g., seismic velocity, attenuation). Previous studies have found several types of temporal changes in material properties with time scales of tens of seconds to several years. Here I systematically analyze temporal changes of fault zone (FZ) site response along the Karadere-Düzce branch of the North Anatolian fault that ruptured during the 1999 İzmit and Düzce earthquake sequences. The coseismic changes are on the order of 20-40%, and are followed by a logarithmic recovery over an apparent time scale of ~1 day. These results provide a bridge between the large-amplitude near-instantaneous changes and the lower-amplitude longer-duration variations observed in previous studies. The temporal changes measured from this high-resolution spectral ratio analysis also provide a refinement for the beginning of the longer more gradual process typically observed by analyzing repeating earthquakes. An improved knowledge on nonlinear site response is critical for better understanding strong ground motions and predicting shaking induced damages. I use the same sliding-window spectral ratio technique to analyze temporal changes in site response associated with the strong ground motion of the Mw6.6 2004 Mid-Niigata earthquake sequence recorded by the borehole stations in Japanese Digital Strong-Motion Seismograph Network (KiK-Net). The coseismic peak frequency drop, peak spectral ratio drop, and the postseismic recovery time roughly scale with the input ground motions when the peak ground velocity (PGV) is larger than ~5 cm/s, or the peak ground acceleration (PGA) is larger than ~100 Gal. The results suggest that at a given site the input ground motion plays an important role in controlling both the coseismic change and postseismic recovery in site response. In a follow-up study, I apply the same sliding-window spectral ratio technique to surface and borehole strong motion records at 6 KiK-Net sites, and stack results associated with different earthquakes that produce similar PGAs. In some cases I observe a weak coseismic drop in the peak frequency when the PGA is as small as ~20-30 Gal, and near instantaneous recovery after the passage of the direct S waves. The percentage of drop in the peak frequency starts to increase with increasing PGA values. A coseismic drop in the peak spectral ratio is also observed at 2 sites. When the PGA is larger than ~60 Gal to more than 100 Gal, considerably stronger coseismic drops of the peak frequencies are observed, followed by a logarithmic recovery with time. The observed weak reductions of peak frequencies with near instantaneous recovery likely reflect nonlinear response with essentially fixed level of damage, while the larger drops followed by logarithmic recovery reflect the generation (and then recovery) of additional rock damage. The results indicate clearly that nonlinear site response may occur during medium-size earthquakes, and that the PGA threshold for in situ nonlinear site response is lower than the previously thought value of ~100-200 Gal. The recent Mw9.0 off the Pacific coast of Tohoku earthquake and its aftershocks generated widespread strong shakings as large as ~3000 Gal along the east coast of Japan. I systematically analyze temporal changes of material properties and nonlinear site response in the shallow crust associated with the Tohoku main shock, using seismic data recorded by the Japanese Strong Motion Network KIK-Net. I compute the spectral ratios of windowed records from a pair of surface and borehole stations, and then use the sliding-window spectral ratios to track the temporal changes in the site response of various sites at different levels of PGA The preliminary results show clear drop of resonant frequency of up to 70% during the Tohoku main shock at 6 sites with PGA from 600 to 1300 Gal. In the site MYGH04 where two distinct groups of strong ground motions were recorded, the resonant frequency briefly recovers in between, and then followed by an apparent logarithmic recovery. I investigate the percentage drop of peak frequency and peak spectral ratio during the Tohoku main shock at different PGA levels, and find that at most sites they are correlated. The third part of my thesis mostly focuses on how seismic waves trigger additional earthquakes at long-range distance, also known as dynamic triggering. Previous studies have shown that dynamic triggering in intraplate regions is typically not as common as at plate-boundary regions. Here I perform a comprehensive analysis of dynamic triggering around the Babaoshan and Huangzhuang-Gaoliying faults southwest of Beijing, China. The triggered earthquakes are identified as impulsive seismic arrivals with clear P- and S-waves in 5 Hz high-pass-filtered three-component velocity seismograms during the passage of large amplitude body and surface waves of large teleseismic earthquakes. I find that this region was repeatedly triggered by at least four earthquakes in East Asia, including the 2001 Mw7.8 Kunlun, 2003 Mw8.3 Tokachi-oki, 2004 Mw9.2 Sumatra, and 2008 Mw7.9 Wenchuan earthquakes. In most instances, the microearthquakes coincide with the first few cycles of the Love waves, and more are triggered during the large-amplitude Rayleigh waves. Such an instantaneous triggering by both the Love and Rayleigh waves is similar to recent observations of remotely triggered 'non-volcanic' tremor along major plate-boundary faults, and can be explained by a simple Coulomb failure criterion. Five earthquakes triggered by the Kunlun and Tokachi-oki earthquakes were recorded by multiple stations and could be located. These events occurred at shallow depth (< 5 km) above the background seismicity near the boundary between NW-striking Babaoshan and Huangzhuang-Gaoliying faults and the Fangshan Pluton. These results suggest that triggered earthquakes in this region likely occur near the transition between the velocity strengthening and weakening zones in the top few kms of the crust, and are likely driven by relatively large dynamic stresses on the order of few tens of KPa.

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34

Sullivan, Brendan. "Delayed triggering of early aftershocks by multiple surface waves circling the earth." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45827.

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It is well known that direct surface waves of large earthquakes are capable of triggering shallow earthquakes and deep tremor at long-range distances. Recent studies have shown that multiple surface waves circling the earth could also remotely trigger microearthquakes. However, it is still not clear whether multiple surface waves returning back to the main shock epicenters could also trigger/modulate aftershock behavior. Here we conduct a study to search for evidence of such triggering by systematically examining aftershock patterns of earthquakes with magnitude ≥ 8 since 1990 that produce observable surface waves circling the globe repeatedly. We specifically examine the 2011 M9 Tohoku-Oki event using a composite catalog of JMA, HiNet and newly detected events obtained by waveform cross correlation. We compute the magnitude of completeness for each sequence, and stack all the sequences together to compute the seismicity and moment rates by sliding data windows. The sequences are also shuffled randomly and these rates are compared to the actual data as well as synthetic aftershock sequences to estimate the statistical significance of the results. Our results suggest that there is some moderate increase of early aftershock activity after a few hours when the surface waves return to the epicentral region. However, we could not completely rule out the possibility that such an increase is purely due to random fluctuations of aftershocks or caused by missing aftershocks in the first few hours after the mainshock.

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35

Sakiroglu, Mehmet. "Positive Outcomes Among The 1999 Duzce Earthquake Survivors: Earthquake Preparedness Behavior And Posttraumatic Growth." Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613479/index.pdf.

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The current study aimed to examine two potential positive outcomes of an earthquake experience, namely posttraumatic growth (PTG) and earthquake preparedness behavior. Variables that may be related to PTG and earthquake preparedness behavior were examined after earthquake victimization by using two models, which were the Person Relative to Event (PrE) Model (Mulilis &amp Duval, 1997) to understand earthquake preparedness behavior, and Model of Life Crises and Personal Growth (Schaefer &amp Moos, 1992) to understand PTG. In order to examine earthquake preparedness behavior, the roles of demographic variables, event-related variables, cognitive appraisal factors, and coping strategies, and in order to examine PTG, environmental factors, system factors, event related factors, earthquake specific coping and cognitive appraisal factors, and general ways of coping responses factors were examined. Data was collected by a questionnaire consisting of three parts. The first part was a socio-demographic information form. The second part of the questionnaire included set of items designed to examine past earthquake experience, the severity of past earthquake experience and reasons to prepare for a possible future earthquake. The third part of the questionnaire consisted of eight scales. These scales were Ways of Coping Inventory (WCI) to measure coping strategies used in stressful situations, Revised and Translated Mulilis-Lippa Earthquake Preparedness Scale (MLEPS) to measure the level of earthquake preparedness behavior, perceived difficulty and perceived effectiveness of being prepared, Religiousness Scale (RS) to measure the level of religious resources of participants, The Multidimensional Scale of Perceived Social Support (MSPSS) to measure perceived adequacy of social support, The Quality of Life Scale (WHOQOL) to measure the quality of life of the participants, Psychological Well-Being Scale to measure the level of psychological well-being of participants, Traumatic Stress Symptom Checklist (TSSC) to measure posttraumatic stress, and Post-traumatic Growth Inventory (PTGI) to measure stress-related growth. One hundred ninety nine adults (105 females and 94 males with an age range of 18 to 73) were participants of the study. The participants were from Kaynasli, D&uuml zce. The participants were selected on the basis of their age, gender, and the type of their houses. They were contacted through home visits. In the result section, the level of the different categories of earthquake preparedness behavior, self-efficacy and outcome efficacy the reasons of preparedness and nonpreparedness for earthquakes, the variables related to earthquake preparedness behavior and PTG were presented. Hierarchical regression analysis results revealed that perceived responsibility to prepare for earthquakes, outcome efficacy, and problem-focused coping were positively and posttraumatic stress was negatively related to earthquake preparedness behavior. As a result of the regression analysis, it was found that being married, perceived social support, well-being, problem-focused coping, and seeking social support coping were significant predictors of the level of PTG. The results of regression analysis also showed that, general problem focused coping was more efficient than earthquake specific active coping after earthquake victimization for the development of PTG. The results of the study were discussed within the relevant literature, shortcomings of the current study, clinical implications and suggestions for future research were proposed.

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36

Bhattacharya, S. "Pile instability during earthquake liquefaction." Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.596628.

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A theory of pile failure, based on buckling instability is proposed in this thesis. The main postulate of this theory is that if piles are too slender they require lateral support from the surrounding soil if they are to avoid buckling instability. During earthquake-induced liquefaction, the soil surrounding the pile loses effective confining stress and can no longer offer sufficient support to the pile. A slender pile may then buckle sideways in the direction of least elastic bending stiffness pushing aside the initially liquefied soil, and eventually rupturing under the increased bending moment and shear force. Lateral loading due to slope movement, inertia or out-of-straightness increases lateral deflections, which in turn induces plasticity in the pile and reduces the buckling load, promoting more rapid collapse. These lateral loads are, however, secondary to the basic requirements that piles in liquefiable soil must be checked against Euler's buckling. This theory has been formulated based on a study of fifteen case histories of pile foundation performance and verified using dynamic centrifuge tests. Analytical studies also support this theory of pile failure. A hypothesis of post-buckling pile-soil interaction is also developed to fit the centrifuge test data. Centrifuge tests were designed in level ground to avoid the effects of lateral spreading and the main aim was to study the effect of axial load as soil liquefies. The failure mode observed in the tests was very similar to those observed in the field in laterally spreading soil. It is concluded in this thesis that it is not necessary to invoke lateral spreading of the soil to cause a pile to collapse. The pile may even collapse before lateral spreading starts. The key parameter identified to distinguish whether the pile pushes the soil (buckling) or the soil pushes the pile (lateral spreading) is the slenderness ratio of the pile in the liquefiable region. The critical value of this parameter is approximately 50. In summary, it has been shown that the current codes of practice for pile design omit considerations necessary to avoid buckling in event of soil liquefaction. These codes are inadequate and buckling needs to be addressed. It has been identified that many of the structures designed based on the current codes of practice may be unsafe and may need retrofitting. Therefore, a design method is proposed taking into consideration the buckling effect.

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37

Luo, Bingmei, and 罗冰梅. "Earthquake shelter park in Dujiangyan." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B47152503.

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38

Sachs, Michael Karl. "Earthquake Scaling, Simulation and Forecasting." Thesis, University of California, Davis, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3646390.

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Abstract (sommario):

Earthquakes are among the most devastating natural events faced by society. In 2011, just two events, the magnitude 6.3 earthquake in Christcurch New Zealand on February 22, and the magnitude 9.0 T&omacr;hoku earthquake off the coast of Japan on March 11, caused a combined total of $226 billion in economic losses. Over the last decade, 791,721 deaths were caused by earthquakes. Yet, despite their impact, our ability to accurately predict when earthquakes will occur is limited. This is due, in large part, to the fact that the fault systems that produce earthquakes are non-linear. The result being that very small differences in the systems now result in very big differences in the future, making forecasting difficult. In spite of this, there are patterns that exist in earthquake data. These patterns are often in the form of frequency-magnitude scaling relations that relate the number of smaller events observed to the number of larger events observed. In many cases these scaling relations show consistent behavior over a wide range of scales. This consistency forms the basis of most forecasting techniques. However, the utility of these scaling relations is limited by the size of the earthquake catalogs which, especially in the case of large events, are fairly small and limited to a few 100 years of events. In this dissertation I discuss three areas of earthquake science. The first is an overview of scaling behavior in a variety of complex systems, both models and natural systems. The focus of this area is to understand how this scaling behavior breaks down. The second is a description of the development and testing of an earthquake simulator called Virtual California designed to extend the observed catalog of earthquakes in California. This simulator uses novel techniques borrowed from statistical physics to enable the modeling of large fault systems over long periods of time. The third is an evaluation of existing earthquake forecasts, which focuses on the Regional Earthquake Likelihood Models (RELM) test: the first competitive test of earthquake forecasts in California.

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39

Van, Dyck Jozef Frans Maria. "Statistical analysis of earthquake catalogs." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/42969.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1986. MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING Bibliography: leaves 262-269. by Jozef Frans Maria Van Dyck. Ph.D.

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40

Mowlai, Shafagh Shannon. "Help - Hurricane Earthquake Loss Prevention." Thesis, California State University, Long Beach, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10751615.

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Climate change is a controversial topic and has individuals arguing that the increased magnitude of the more recent natural disasters is significantly due to climate change happening. According to Weixiao Han, there has been an occurrence of over 22,000 natural disasters all around the world from 1900s to current day. Disaster relief preparedness and resources have been crucial in aiding the population at risk. Hurricane Earthquake Loss Prevention – HELP – focuses on decreasing the number of fatalities and damages during and after a natural disaster occurs in long-term care facilities and nursing homes. Hurricane Earthquake Loss Prevention aims to support these healthcare facilities by providing them with the right tools to aid and prevent injuries when a natural disaster strikes. This proposal will provide a breakdown of how HELP aims to provide disaster relief across the nation.

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41

Stathas, Alexandros. "Numerical modeling of earthquake faults." Thesis, Ecole centrale de Nantes, 2021. http://www.theses.fr/2021ECDN0053.

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Lors d’un glissement sismique, l’énergie libérée par la décharge élastique des blocs de terre adjacente peut être séparée en trois parties principales : L’énergie qui est rayonnée à la surface de la terre (_ 5% du budget énergétique total), l’énergie de fracture pour la création de nouvelles surfaces de faille et enfin, l’énergie dissipée à l’intérieur d’une région de la faille, d’épaisseur finie, que l’on appelle le “fault gouge ". Cette région accumule la majorité du glissement sismique. Estimer correctement la largeur de fault gouge est d’une importance capitale pour calculer l’énergie dissipée pendant le séisme, le comportement frictionnel de la faille et les conditions de nucléation de la faille sous la forme d’un glissement sismique ou asismique.Dans cette thèse, approches différentes de régularisation ont été explorées pour l’estimation de la largeur de localisation de la zone de glissement principal de la faille pendant le glissement cosmique. Celles-ci comprennent l’application de la viscosité et des couplages multiphasiques dans le continuum classique de Cauchy, et l’introduction d’un continuum micromorphe de Cosserat du premier ordre. Tout d’abord, nous nous concentrons sur le rôle de la régularisation visqueuse dans le contexte des analyses dynamiques, en tant que méthode de régularisation de la localisation des déformations. Nous étudions le cas dynamique d’un continuum de Cauchy classique adoucissant à la déformation et durcissant à la vitesse de déformation. En appliquant l’analyse de stabilité de Lyapunov, nous montrons que l’introduction de la viscosité est incapable d’empêcher la localisation de la déformation sur un plan mathématique et la dépendance de du maillage des éléments finis.Nous effectuons des analyses non linéaires en utilisant le continuum de Cosserat dans le cas de grands déplacements par glissement sismique de fault gouge par rapport à sa largeur. Le continuum de Cosserat nous permet de rendre compte de l’énergie dissipée pendant un séisme et du rôle de la microstructure dans l’évolution de la friction de la faille. Nous nous concentrons sur l’influence de la vitesse de glissement sismique sur le mécanisme d’assidument frictionnel de la pressurisation thermique. Nous remarquons que l’influence des conditions aux limites dans la diffusion du fluide interstitiel à l’intérieur de fault gouge, conduit à une reprise du frottement après l’affaiblissement initial. De plus, un mode de localisation de déformation en mouvement est présent pendant le cisaillement de la couche, introduisant des oscillations dans la réponse du frottement. Ces oscillations augmentent le contenu spectral du séisme. L’introduction de la viscosité dans le mode ci-dessus, conduit à un comportement de "rate and state" sans l’introduction d’une variable interne. Nos conclusions sur le rôle de la pressurisation thermique pendant le cisaillement de fault gouge sont en accord qualitatif avec les nouveaux résultats expérimentaux disponibles. Enfin, sur la base des résultats numériques, nous étudions les hypothèses du modèle actuel de glissement sur un plan mathématique proposent à la littérature. Le rôle des conditions aux limites et du mode de localisation des déformations dans l’évolution du frottement de la faille pendant le glissement sismique. Le cas d’un domaine délimité et d’un mode de localisation de la déformation en mouvement est examiné dans le contexte d’un glissement sur un plan mathématique sous pressurisation thermique. Nos résultats étoffent le modèle original dans un contexte plus général During coseismic slip, the energy released by the elastic unloading of the adjacent earth blocks can be separated in three main parts: The energy that is radiated to the earth’s surface (_ 5% of the whole energy budget), the fracture energy for the creation of new fault surfaces and finally, the energy dissipated inside a region of the fault, with finite thickness, which is called the fault gauge. This region accumulates the majority of the seismic slip. Estimating correctly the width of the fault gauge is of paramount importance in calculating the energy dissipated during the earthquake, the fault’s frictional response, and the conditions for nucleation of the fault in the form of seismic or aseismic slip.In this thesis different regularization approaches were explored for the estimation of the localization width of the fault’s principal slip zone during coseismic slip. These include the application of viscosity and multiphysical couplings in the classical Cauchy continuum, and the introduction of a first order micromorphic Cosserat continuum. First, we focus on the role of viscous regularization in the context of dynamical analyses, as a method for regularizing strain localization. We study the dynamic case for a strain softening strain-rate hardening classical Cauchy continuum, and by applying the Lyapunov stability analysis we show that introduction of viscosity is unable to prevent strain localization on a mathematical plane and mesh dependence.We perform fully non linear analyses using the Cosserat continuum under large seismic slip displacements of the fault gouge in comparison to its width. Cosserat continuum provides us with a proper account of the energy dissipated during an earthquake and the role of the microstructure in the evolution of the fault’s friction. We focus on the influence of the seismic slip velocity to the weakening mechanism of thermal pressurization. We notice that the influence of the boundary conditions in the diffusion of the pore fluid inside the fault gouge, leads to frictional strength regain after initial weakening. Furthermore, a traveling strain localization mode is present during shearing of the layer introducing oscillations in the frictional response. Such oscillations increase the spectral content of the earthquake. Introduction of viscosity in the above mode, leads to a rate and state behavior without the introduction of a specific internal state variable. Our conclusions about the role of thermal pressurization during shearing of the fault gouge, agree qualitatively with newly available experimental results.Finally, based on the numerical findings we investigate the assumptions of the current model of a slip on a mathematical plane, in particular the role of the boundary conditions and strain localization mode in the evolution of the fault’s friction during coseismic slip. The case of a bounded domain and a traveling strain localization mode are examined in the context of slip on a mathematical plane under thermal pressurization. Our results expand the original model in a more general context

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42

Xia, Kaiwen Rosakis Ares J. "Laboratory investigations of earthquake dynamics /." Diss., Pasadena, Calif. : California Institute of Technology, 2005. http://resolver.caltech.edu/CaltechETD:etd-02262005-161824.

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43

Hill-Butler, C. "Evaluating the effect of large magnitude earthquakes on thermal volcanic activity : a comparative assessment of the parameters and mechanisms that trigger volcanic unrest and eruptions." Thesis, Coventry University, 2015. http://curve.coventry.ac.uk/open/items/5f612a7d-ebbf-4d38-90aa-89c4984a1c0f/1.

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Volcanic eruptions and unrest have the potential to have large impacts on society causing social, economic and environmental losses. One of the primary goals of volcanological studies is to understand a volcano’s behaviour so that future instances of unrest or impending eruptions can be predicted. Despite this, our ability to predict the onset, location and size of future periods of unrest remains inadequate and one of the main problems in forecasting is associated with the inherent complexity of volcanoes. In practice, most reliable forecasts have employed a probabilistic approach where knowledge of volcanic activity triggers have been incorporated into scenarios to indicate the probability of unrest. The proposed relationship between large earthquakes and volcanic activity may, therefore, indicate an important precursory signal for volcanic activity forecasting. There have been numerous reports of a spatial and temporal link between volcanic activity and high magnitude seismic events and it has been suggested that significantly more periods of volcanic unrest occur in the months and years following an earthquake than expected by chance. Disparities between earthquake-volcano assessments and variability between responding volcanoes, however, has meant that the conditions that influence a volcano’s response to earthquakes have not been determined. Using data from the MODVOLC algorithm, a proxy for volcanic activity, this research examined a globally comparable database of satellite-derived volcanic radiant flux to identify significant changes in volcanic activity following an earthquake. Cases of potentially triggered volcanic activity were then analysed to identify the earthquake and volcano parameters that influence the relationship and evaluate the mechansisms proposed to trigger volcanic activity following an earthquake. At a global scale, this research identified that 57% [8 out of 14] of all large magnitude earthquakes were followed by increases in global volcanic activity. The most significant change in volcanic radiant flux, which demonstrates the potential of large earthquakes to influence volcanic activity at a global scale, occurred between December 2004 and April 2005. During this time, new thermal activity was detected at 10 volcanoes and the total daily volcanic radiant flux doubled within 52 days. Within a regional setting, this research also identified that instances of potentially triggered volcanic activity were statistically different to instances where no triggering was observed. In addition, assessments of earthquake and volcano parameters identified that earthquake fault characteristics increase the probability of triggered volcanic activity and variable response proportions at individual volcanoes and regionally demonstrated the critical role of the state of the volcanic system in determining if a volcano will respond. Despite the identification of these factors, this research was not able to define a model for the prediction of volcanic activity following earthquakes and, alternatively, proposed a process for response. In doing so, this thesis confirmed the potential use of earthquakes as a precursory indicator to volcanic activity and identified the most likely mechanisms that lead to seismically triggered volcanic unrest.

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44

Rockaway, Thomas D. "Spatial assessment of earthquake induced geotechnical hazards." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/20038.

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45

McCormack, Thomas C. "A Methodology for Regional Seismic Damage Assessment and Retrofit Planning for Existing Buildings." PDXScholar, 1996. https://pdxscholar.library.pdx.edu/open_access_etds/1239.

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Recent geologic research has shown that earthquakes more destructive than formerly expected are likely to occur in the Pacific Northwest. To mitigate catastrophic loss, planners are gathering information to make decision on implementing regional seismic retrofit programs. This research develops a model to estimate regional earthquake losses for existing buildings, and determine optimal retrofit priorities and budgets. Fragility curves are developed to provide earthquake damage estimates for a range of seismic intensities. The published earthquake damage estimates of a large group of prominent earthquake engineering experts are extended to include the combined effect of structure type, earthquake-sensitive variations in building design, site-specific soil conditions, and local seismic design practice. Building inventory data from a rapid visual screening survey of individual buildings form the basis for modeling structural variations. Earthquake Hazard Maps are the basis of modeling the effect on building damage of ground motion amplification, soil liquefaction, and slope instability. Published retrofit effectiveness estimates and retrofit cost data are used to estimate post-retrofit damage avoided, lives saved, and retrofit cost. A Building Classification System is formulated to aggregate buildings with similar retrofit benefit magnitudes. A cost-benefit analysis is used as the basis for a retrofit prioritization and efficiency analysis, to establish the cut-off point for an optimal retrofit program. Results from an Expected Value and a Scenario Earthquake Event are compared. Regional Earthquake Loss and Retrofit Analysis Program (REAL-RAP) software was developed, and used to make a loss estimate for more than 7,500 buildings inventoried in the 1993 Portland Seismic Hazards Survey. One hundred percent of the loss of life is attributed to only 10-percent of the buildings. A retrofit analysis is made for a Design Basis Earthquake. Twelve-percent of the building inventory was identified for the optimal retrofit program, wherein 98-percent of the loss of life is avoided at less than one-quarter the cost of retrofitting all the buildings. An alternate optimal retrofit program was determined using an Expected Value Analysis. Most of the buildings in the Design Basis Earthquake optimal retrofit program are also contained in the alternate program.

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46

Lambie, Emily Susan. "Human response to earthquake shaking : analysis of video footage of the 2010-2011 Canterbury earthquake sequence." Thesis, University of Canterbury. Geological Sciences, 2014. http://hdl.handle.net/10092/9431.

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Research on human behaviour during earthquake shaking has identified three main influences of behaviour: the environment the individual is located immediately before and during the earthquake, in terms of where the individual is and who the individual is with at the time of the earthquake; individual characteristics, such as age, gender, previous earthquake experience, and the intensity and duration of earthquake shaking. However, little research to date has systematically analysed the immediate observable human responses to earthquake shaking, mostly due to data constraints and/or ethical considerations. Research on human behaviour during earthquakes has relied on simulations or post-event, reflective interviews and questionnaire studies, often performed weeks to months or even years following the event. Such studies are therefore subject to limitations such as the quality of the participant's memory or (perceived) realism of a simulation. The aim of this research was to develop a robust coding scheme to analyse human behaviour during earthquake shaking using video footage captured during an earthquake event. This will allow systematic analysis of individuals during real earthquakes using a previously unutilized data source, thus help develop guidance on appropriate protective actions. The coding scheme was developed in a two-part process, combining a deductive and inductive approach. Previous research studies of human behavioral response during earthquake shaking provided the basis for the coding scheme. This was then iteratively refined by applying the coding scheme to a broad range of video footage of people exposed to strong shaking during the Canterbury earthquake sequence. The aim of this was to optimise coding scheme content and application across a broad range of scenarios, and to increase inter-coder reliability. The methodology to code data will enhance objective observation of video footage to allow cross-event analysis and explore (among others): reaction time, patterns of behaviour, and social, environmental and situational influences of behaviour. This can provide guidance for building configuration and design, and evidence-based recommendations for public education about injury-preventing behavioural responses during earthquake shaking.

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47

Padgett, Jamie Ellen. "Seismic Vulnerability Assessment of Retrofitted Bridges Using Probabilistic Methods." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14469.

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The central focus of this dissertation is a seismic vulnerability assessment of retrofitted bridges. The objective of this work is to establish a methodology for the development of system level fragility curves for typical classes of retrofitted bridges using a probabilistic framework. These tools could provide valuable support for risk mitigation efforts in the region by quantifying the impact of retrofit on potential levels of damage over a range of earthquake intensities. The performance evaluation includes the development of high-fidelity three-dimensional nonlinear analytical models of bridges retrofit with a range of retrofit measures, and characterization of the response under seismic loading. Sensitivity analyses were performed to establish an understanding of the appropriate level of uncertainty treatment to model, assess, and propagate sources of uncertainty inherent to a seismic performance evaluation for portfolios of structures. Seismic fragility curves are developed to depict the impact of various retrofit devices on the seismic vulnerability of bridge systems. This work provides the first set of fragility curves for a range of bridge types and retrofit measures. Framework for their use in decision making for identification of viable retrofit measures, performance-based retrofit of bridges, and cost-benefit analyses are illustrated. The fragility curves developed as a part of this research will fill a major gap in existing seismic risk assessment software, and enable decision makers to quantify the benefits of various retrofits.

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48

Burden, Lindsay Ivey. "Forecasting earthquake losses in port systems." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/43615.

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Ports play a critical role in transportation infrastructure, but are vulnerable to seismic hazards. Downtime and reduced throughput from seismic damage in ports results in significant business interruption losses for port stakeholders. Current risk management practices only focus on the effect of seismic hazards on individual port structures. However, damage and downtime of these structures has a significant impact on the overall port system's ship handling operations and the regional, national, and even international economic impacts that result from extended earthquake-induced disruption of a major container port. Managing risks from system-wide disruptions resulting from earthquake damage has been studied as a central element of a Grand Challenge project sponsored by the National Science Foundation Network for Earthquake Engineering Simulation (NEES) program. The following thesis presents the concepts and methods developed for the seismic risk management of a port-wide system of berths. In particular the thesis discusses the framework used to calculated port losses: the use of spatially correlated ground motion intensity measures to estimate damage to pile-supported marginal wharves and container cranes of various configurations via fragility relationships developed by project team members, repair costs and downtimes subsequently determined via repair models for both types of structures, and the impact on cargo handling operations calculated via logistical models of the port system. Results are expressed in the form of loss exceedance curves than include both repair/replacement costs and business interruption losses. The thesis also discusses how the results from such an analysis might be used by port decision makers to make more informed decisions in design, retrofit, operational, and other seismic risk management options.

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Sakiroglu, Mehmet. "Variables Related To Earthquake Preparedness Behavior." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606369/index.pdf.

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This study examined some factors to understand earthquake preparedness behavior. The roles of demoghraphic characteristics of the participants, trait anxiety, the severity of exposure of past earthquake experience, outcome efficacy (perceived effectiveness of preparedness), self efficacy (perceived difficulty of preparedness), impact of past experience (avoidance and intrusion symptom levels of impact of event scale), threat perception, locus of control and four factors of coping strategies (problem focused approach, fatalistic coping, helplessness/self blaming approach and seeking social support) in predicting earthquake preparedness behavior were studied. Data was collected by a questionnaire consisting of three parts. The first part was a socio-demographic information form. The second part of the questionnaire included sets of items designed to examine past earthquake experience, the severity of past earthquake experience, estimations of the severity of a possible future earthquake, probability of occurence of a potential future earthquake, reasons to prepare and responsibility related to preparedness. The third part of the questionnaire consisted of four scales. These scales were Ways of Coping Inventory (WCI) to measure coping strategies in stressful situations, Impact of Event Scale (IES) to measure current subjective distress trait part of the State-Trait Anxiety Inventory (STAI) to measure the level of trait anxiety of persons and Revised and Translated Mulilis- Lippa Earthquake Preparedness Scale (MLEPS) to measure the level of earthquake preparedness behavior, perceived difficulty of being prepared and perceived effectiveness of being prepared. Two hundred eighteen adults (120 females and 98 males with an age range of 20 to 67) were participants of the study. There were participants from all 32 districts of istanbul in the sample. Data was collected in two departments of Istanbul Technical University, which were architecture and civil engineering, Psychology Department of Middle East Technical University, High School of KabataS Erkek Lisesi and istanbul Bah&ccedil elievler Primary School. Participants were parents of students. The regression analysis results revealed that, severity of exposure of past earthquake experience, avoidance, self-efficacy and outcome efficacy were found to be significantly related to earthquake preparedness. Considering significant predictors, the severity of the exposure to past earthquake experience and perceived effectiveness of being prepared increases the level of earthquake preparedness behavior perceived difficulty of being prepared and avoidance symptom levels of impact of event scale decreases it. As an evidence to Person Relative to Event Model, the results of the current study showed that there is a significant relationship between both perceived effectiveness of being prepared and perceived difficulty of being prepared with the level of earthquake preparedness level. The importance of the results of the current study and their shortcomings were discussed within the earlier findings on disaster preparedness literature.

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50

Elghazouli, Ahmed Youssef. "Earthquake resistance of composite beam-columns." Thesis, Imperial College London, 1991. http://hdl.handle.net/10044/1/7906.

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