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Analysis of Hierarchical Structure of Seismic Activity: Bayesian Approach to Forecasting Earthquakes / 地震活動の階層構造の解析:地震予測に向けたベイズ的アプローチTanaka, Hiroki 25 March 2024 (has links)
京都大学 / 新制・課程博士 / 博士(情報学) / 甲第25438号 / 情博第876号 / 京都大学大学院情報学研究科数理工学専攻 / (主査)教授 梅野 健, 教授 辻本 諭, 教授 田口 智清 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
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Effect of seismic loads on water-retaining structures in areas of moderate seismicityFourie, Johanna Aletta 03 1900 (has links)
Thesis (MScEng (Civil Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Water-retaining structures are commonly used in South Africa for the storage of potable water and
waste water. However, a South African code pertaining to the design of concrete water-retaining
structures do not currently exist and therefore use is made of the British Standard BS 8007 (1987).
For the design of concrete water-retaining structures in South Africa, only the hydrostatic loads are
considered while forces due to seismic activity are often neglected even though seismic excitations
of moderate magnitude occur within some regions of the country. Hence, the primary aim of this
study was to determine whether seismic activity, as it occurs in South Africa, has a significant
influence on water-retaining structures and whether it should be considered as a critical load case.
In order to assess the influence of seismic activity on the design of water-retaining structures the
internal forces in the wall and the required area of reinforcement were compared. Comparisons
were made between the seismic analyses and static analyses for both the ultimate and serviceability
limit states. In order to obtain the internal forces in the wall use was made of an appropriate Finite
element model. Three Finite element models were investigated in this study and the accuracy of
each model was assessed based on the fundamental frequency, base shear force and overturning
moment. These values were compared to the values obtained with the numerical method presented
by Veletsos (1997) which was verified with Eurocode 8: Part 4 (2006).
The results obtained indicated that seismic excitations of moderate magnitude do have a significant
influence on the reinforcement required in concrete water-retaining structures. For both the
ultimate limit state and serviceability limit state the required reinforcement increased significantly
when seismic loads were considered in the design. As in the case for static design of water-retaining
structures, the serviceability limit state also dominated the design of these structures under seismic
loading. / AFRIKAANSE OPSOMMING: Beton waterhoudende strukture in Suid-Afrika word op ‘n gereelde basis gebruik vir die stoor van
drink- sowel as afvalwater. ‘n Suid-Afrikaanse kode vir die ontwerp van hierdie strukture bestaan
egter nie en dus word die Britse kode BS 8007 (1987) hiervoor gebruik. Vir ontwerp doeleindes word
soms slegs die hidrostatiese kragte beskou terwyl kragte as gevolg van seismiese aktiwiteite nie
noodwendig in berekening gebring word nie. Seismiese aktiwiteite van gematigde grootte kom egter
wel voor in sekere dele van Suid-Afrika. Die hoofdoel van hierdie studie was dus om die invloed van
seismiese aktiwiteite, soos voorgeskryf vir Suid-Afrikaanse toestande, op beton waterhoudende
strukture te evalueer asook om te bepaal of dit ‘n kritiese lasgevalle sal wees.
Vir hierdie doel is die interne kragte asook die area staal bewapening vir elk van die statiese en
dinamiese lasgevalle vergelyk. Vergelykings is getref tussen die dinamiese en statiese resultate vir
beide die swigtoestand en die diensbaarheidstoestand. Vir die bepaling van die interne kragte is
gebruik gemaak van eindige element modelle. Tydens hierdie studie was drie eindige element
modelle ondersoek en die akkuraatheid van elk geëvalueer op grond van die fundamentele
frekwensie, die fondasie skuifkrag en die omkeermoment. Hierdie waardes was ondermeer bereken
met twee numeriese metodes soos uiteengesit in Veletsos (1997) en Eurocode 8: Part 4 (2006).
Die resultate dui daarop dat die invloed van seismiese aktiwiteite op beton waterhoudende
strukture in Suid-Afrika nie weglaatbaar klein is nie en wel in berekening gebring behoort te word
tydens die ontwerp. Die interne kragte vir beide die swigtoestand en diensbaarheidstoestand is
aansienlik hoër vir die seismiese lasgeval as vir die statiese geval. Die diensbaarheidstoestand het
deurentyd die ontwerp van beton waterhoudende strukture vir seismiese toestande oorheers.
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The effect of seismic activity on reinforced concrete frame structures with infill masonry panelsJarvis, Wesley James 04 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Certain regions within the Western Cape Province are at risk of a moderate intensity
earthquake. It is therefore crucial that infrastructure in these areas be
designed to resist its devastating effect. Numerous types of structural buildings
exist in these seismic prone areas. The most common types are either reinforced
concrete framed buildings with masonry infill or unreinforced masonry
buildings. Many of these buildings predate the existence of the first loading
code of 1989 which provided regulations for seismic design. The previous code
was superseded in 2010 with a code dedicated to providing guidelines for seismic
design of infrastructure. A concern was raised whether these buildings
meet the requirements of the new code. A numerical investigation was performed
on a representative reinforced concrete framed building with masonry
infill to determine whether the building meets the new code’s requirements.
The results from the investigation show that the stresses at critical points in
the columns exceed the codified requirements, thus leading to local failure.
After careful review it was discovered that these local failures in the columns
will most likely lead to global failure of the building. / AFRIKAANSE OPSOMMING: In sekere streke in die Wes-Kaap bestaan daar risiko van matige intensiteit
aardbewings. Dit is dus noodsaaklik dat die infrastruktuur in hierdie gebiede
ontwerp word om die vernietigende uitwerking te weerstaan. Gebous
met verskillende tipes strukturele uitlegte kom in hierdie gebied voor. Die
mees algemene struktuur tipe is gewapende beton-raam geboue met baksteen
invol panele sowel as ongewapende baksteen geboue. Baie van hierdie geboue
is gebou voor die eerste las-kode van 1989 wat regulasies vir seismiese ontwerp
voorsien in gebruik geneem is. Die vorige kode is vervang in 2010 met ’n
kode toegewy tot die verskaffing van riglyne vir seismiese ontwerp van infrastruktuur.
Kommer het ontstaan of hierdie geboue voldoen aan die vereistes
van die nuwe kode. ’n Numeriese ondersoek is uitgevoer op ’n verteenwoordigende
gewapende beton geraamde gebou met baksteen panele om te bepaal
of die gebou voldoen aan die nuwe kode vereistes rakende sismiese ontwerp.
Die resultate van die ondersoek toon dat die spanning op kritieke punte in
die kolomme die gekodifiseerde vereistes oorskry, wat tot plaaslike faling lei.
Na verdere onderssoek is dit bepaal dat die plaaslike faling in die kolomme
waarskynlik tot globale faling van die gebou sal lei.
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Defining an Earthquake Intensity Based Method for a Rapid Earthquake Classification System / Definiera en intensitets-baserad metod för snabb klassificering av jordbävningar och förutsägelse av skadorBäckman, Erik January 2017 (has links)
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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Über Erdbeben - Ein Versuch zur Erweiterung seismologischer DarstellungsweisenDombois, Florian 14 October 1998 (has links)
Die vorliegende Arbeit beschäftigt sich mit dem Verständnis und der Erkenntnis von Erdbeben. Es ist der Versuch, sich diesem Naturereignis anzunähern und es auf unterschiedliche Weisen zu begreifen: (i) Was eigentlich ist ein Erdbeben? Was macht es aus? Worin besteht seine Faszination? (ii) Wie wurden und werden Erdbeben in der europäischen Text- und Bildtradition dargestellt? (iii) Welches Verhältnis besteht zwischen der Form der Darstellung und dem Inhalt 'Erdbeben'? Wie verändert sich das Phänomen, wenn die Darstellungsform sich verändert? (iv) Und schließlich: welche Form scheint am geeignetsten, um Erdbeben darzustellen? Um diesen Fragen nachzugehen, untersucht die Arbeit 16 Beispiele auf das ihnen immanente Verhältnis von Form und Inhalt. Die Beispiele werden dabei so ausgewählt, daß sich ein möglichst breites formales Spektrum ergibt: Neben den heute üblichen Formen der Erdbebendarstellung, die am Beispiel der Reaktion auf das Erdbeben von Kobe behandelt werden (§ 13 Seismologischer Artikel, § 14 Pressemeldung, § 15 Erdbebensimulator im Natural History Museum, London), beschäftigt sich die Arbeit mit Beispielen sowohl aus der griechischen Tradition (§ 1 Poseidon-Mythos, § 2 Aristoteles' 'Meteorologica'), als auch aus der römischen (§ 3 Senecas 'Naturales Quaestiones', § 4 'Aetna'), als auch aus der christlichen (§ 5 'Bibel', § 6 Thomas von Aquins Aristoteles-Kommentar, § 7 Apokalypse-Illustrationen aus dem Hochmittelalter); desweiteren wird eine Gruppe von Darstellungen untersucht, die nach dem Erdbeben von Lissabon 1755 entstanden sind (§ 8 Bänkellieder, § 9 Voltaire, § 10 Kupferstiche von Le Bas, § 11 Kant, § 12 John Michell). Am Ende der Sammlung wird der Science-Fiction Roman 'Richter 10' von Clarke und McQuay (§ 16) näher betrachtet. In einem abschließenden Resüme beklage ich, daß die Form naturwissenschaftlicher Darstellung unsinnlich und verfügend ist. Die Dissertation soll daher in einen Gegenentwurf münden, und so reflektiert das letzte Kapitel (§ 17) die Erfahrung der 16 vorangegangen. Ich schlage hier die Transponierung der Erdbewegung in das Akustische vor und führe dies exemplarisch für ein Beben aus Chile von 1994 durch. Eine Reihe weiterführender Überlegungen zeigt, daß über die formale Dimension hinaus die akustische Transformation auch inhaltlich vielversprechend ist: Weitab vom naturwissenschaftlichen mainstream nämlich bringt diese ganz neue Form die Möglichkeit mit sich, die Frage der Erdbebenprognose auf ungewohnte Weise zu stellen, und somit tut sich hier parallel zu einer neuen Darstellungsform auch ein neues Forschungsfeld auf. / The dissertation in hand is engaged in the understanding and cognition of earthquakes. Essentially it is the attempt to draw near the natural phenomenon and to broaden our conception of it: (i) What actually is an earthquake? What makes it up? Why might it be fascinating? (ii) How were and how are earthquakes depicted in the textual and pictoral tradition in Europe? (iii) How is the form of depiction related to the content 'earthquake'? How does the phenomenon change when the form of depiction is altered? (iv) And last not least: which form seems to be most suitable for the depiction of an earthquake? According to the above questions 16 'earthquake-depictions' are sampled to investigate the relation between form and content. The attempt is made to provide a collection of great diversity in form: Today's usual manner of earthquake depiction is represented by the reaction, the earthquake of Kobe has received (§ 13 seismological article, § 14 press releases, § 15 earthquake simulator in the Natural History Museum London); then there are chosen: two samples of the Old Greek tradition (§ 1 myth of Poseidon, § 2 Aristoteles' 'Meteorologica'), further two from the Roman tradition (§ 3 Seneca's 'Naturales Quaestiones', § 4 'Aetna'), and two from the Christian tradition (§ 5 'Bible', § 6 Thomas Aquinas on Aristotle's 'Meteorologica'); furthermore there are some samples looked upon that show reaction on the Lisbon earthquake of 1755 (§ 8 shocking ballads, § 9 Voltaire, § 10 copper engravings of Le Bas, § 11 Immanuel Kant, § 12 John Michell). Last not least the science fiction novel 'Richter 10' by Clarke and McQuay (§ 16) is examined. Finally I complain that the manner of scientific depiction is 'un-sensual' and disposing. Therefore the dissertation is meant to flow into a counter-project. The last chapter scrutinizes the experience of the investigations before under a wider angle. In consequence I suggest to investigate an acoustical transponation of the earth's movements. An example of the new kind of sound that emerges from that is drawn from a 1994 earthquake in Chile. A range of further considerations show that not only the form of the acoustical transformation seems promising but also its content: far from the mainstream of seismological research the new acoustic form renders the question of earthquake prediction in a unusual but new and fairly easy way. All of this results in me hoping that the releasing of this new form of depiction triggers of a new field of scientific research at the same time.
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Performance-Based Liquefaction Triggering Analyses with Two Liquefaction Models Using the Cone Penetration TestArndt, Alex Michael 01 August 2017 (has links)
This study examines the use of performance-based engineering in earthquake liquefaction hazard analysis with Cone Penetration Test data (CPT). This work builds upon previous research involving performance-based liquefaction analysis with the Standard Penetration Test (SPT). Two new performance-based liquefaction triggering models are presented herein. The two models used in this liquefaction analysis are modified from the case-history based probabilistic models proposed by Ku et al. (2012) and Boulanger and Idriss (2014). Using these models, a comparison is made between the performance-based method and the conventional pseudo-probabilistic method. This comparison uses the 2014 USGS probabilistic seismic hazard models for both methods. The comparison reveals that, although in most cases both methods predict similar liquefaction hazard using a factor of safety against liquefaction, by comparing the probability of liquefaction, the performance-based method on average will predict a smaller liquefaction hazard.
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Achieving Operational Seismic Performance of RC Bridge Bents Retrofitted with Buckling-Restrained BracesBazáez Gallardo, Ramiro Andrés Gabriel 13 February 2017 (has links)
Typical reinforced concrete (RC) bridges built prior to 1970 were designed with minimum seismic consideration, leaving numerous bridges highly susceptible to damage following an earthquake. In order to improve the seismic behavior of substandard RC bridges, this study presents the seismic performance of reinforced concrete bridge bents retrofitted and repaired using Buckling-Restrained Braces (BRBs) while considering subduction zone earthquake demands. In order to reflect displacement demands from subduction ground motions, research studies were conducted to develop quasi-static loading protocols and then investigate their effect on structural bridge damage. Results suggested that subduction loading protocols may reduce the displacement ductility capacity of RC bridge columns and change their failure mode. The cyclic performance of reinforced concrete bridge bents retrofitted and repaired using BRBs was experimentally evaluated using large-scale specimens and the developed loading histories. Three BRB specimens were evaluated with the aim of assessing the influence of these components on the overall performance of the retrofitted and repaired bents. Additionally, subassemblage tests were conducted in an effort to study the response of these elements and to allow for refined nonlinear characterization in the analysis of the retrofitted and repaired systems. The results of the large-scale experiments and analytical studies successfully demonstrated the effectiveness of utilizing buckling-restrained braces for achieving high displacement ductility of the retrofitted and repaired structures, while also controlling the damage of the existing vulnerable reinforced concrete bent up to an operational performance level.
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Assessment of Seismic Retrofit Prioritization Methodology for Oregon's Highway Bridges Based on the Vulnerability of Highway SegmentsMehary, Selamawit Tesfayesus 18 July 2018 (has links)
Geologists have indicated that the question is not if a catastrophic earthquake will occur in Oregon but when one will occur. Scientists estimate that there is close to 40 percent conditional probability that a Cascadia subduction zone earthquake of magnitude 8.0 or above will strike Oregon in the next 50 years. In addition, the majority of Oregon's bridge inventory was built prior to the current understanding of bridge response and prior to current understanding of the expected earthquake demands. In order to minimize potential bridge damage in the case of an earthquake, one approach is to retrofit seismically deficient bridges. However, often times the decision maker is faced with the difficulty of selecting only a few bridges within the inadequate ones. Hence, the issue of prioritizing upgrading naturally arises. The goal of this study is to assess and refine bridge prioritization methodology to be utilized for ranking Oregon's bridge inventory. CFRP retrofit has been experimentally and analytically evaluated to demonstrate the effectiveness of the technique and was found to be an efficient and economical option. A vulnerability assessment estimates that close to 30 percent of Oregon's highway bridge inventory will sustain moderate damage to collapse. However, retrofitting two most common bridge types in the inventory will reduce the number of damaged bridges by about 70 percent. A cost-benefit assessment that takes into consideration direct and indirect costs associated with damaged bridges and retrofitting of bridges shows that the benefit is up to three times the cost to retrofit. The same principle was applied to rank twelve highway segments for seismic retrofit considered important by Oregon Department of Transportation. One selected segment was considered to be retrofitted and vulnerability assessed. The benefit to cost ratios for each assessment was compared and the highway segments were ranked accordingly. The top five segments in the ranking happen to be located in the East-West corridor connecting I-5 to US-101.
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Performance-Based Seismic Monitoring of Instrumented BuildingsRoohi, Milad 01 January 2019 (has links)
This dissertation develops a new concept for performance-based monitoring (PBM) of instrumented buildings subjected to earthquakes. This concept is achieved by simultaneously combining and advancing existing knowledge from structural mechanics, signal processing, and performance-based earthquake engineering paradigms. The PBM concept consists of 1) optimal sensor placement, 2) dynamic response reconstruction, 3) damage estimation, and 4) loss analysis. Within the proposed concept, the main theoretical contribution is the derivation of a nonlinear model-based observer (NMBO) for state estimation in nonlinear structural systems. The NMBO employs an efficient iterative algorithm to combine a nonlinear model and limited noise-contaminated response measurements to estimate the complete nonlinear dynamic response of the structural system of interest, in the particular case of this research, a building subject to an earthquake. The main advantage of the proposed observer over existing nonlinear recursive state estimators is that it is specifically designed to be physically realizable as a nonlinear structural model. This results in many desirable properties, such as improved stability and efficiency.
Additionally, a practical methodology is presented to implement the proposed PBM concept in the case of instrumented steel, wood-frame, and reinforced concrete buildings as the three main types of structural systems used for construction in the United States. The proposed methodology is validated using three case studies of experimental and real-world large-scale instrumented buildings. The first case study is an extensively instrumented six-story wood frame building tested in a series of full-scale seismic tests in the final phase of the NEESWood project at the E-Defense facility in Japan. The second case study is a 6-story steel moment resisting frame building located in Burbank, CA, and uses the recorded acceleration data from the 1991 Sierra Madre and 1994 Northridge earthquakes. The third case is a seven-story reinforced concrete structure in Van Nuys, CA, which was severely damaged during the 1994 Northridge earthquake.
The results presented in this dissertation constitute the most accurate and the highest resolution seismic response and damage measure estimates obtained for instrumented buildings. The proposed PBM concept will help structural engineers make more informed and swift decisions regarding post-earthquake assessment of critical instrumented building structures, thus improving earthquake resiliency of seismic-prone communities.
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Catalog of Swarm Earthquakes in Vogtland /West Bohemia in 2008/09Hiemer, Stefan, Rößler, Dirk, Scherbaum, Frank January 2010 (has links)
The document contains the catalog of earthquakes in Vogtland /West Bohemia within the period of 2008/10/19 -to- 2009/03/16. The events were recorded by a seismic mini-array operated by the Institute of Earthsciences, University of Postdam. / Das Dokument enthält einen Katalog von Erdbeben im Vogtland/Westböhmen im Zeitraum 2008/10/19 -bis- 2009/03/16. Die Erdbeben wurden mit Hilfe eines seismologischen Miniarrays, welches vom Institut für Geowissenschaften, Universität Potsdam, aufgestellt wurde, registriert.
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