Die relativ hohe seismische Aktivität der Tote-Meer-Störungszone (Dead Sea Fault Zone - DSFZ) ist mit einem hohen Gefahrenpotential verbunden, welches zu einem erheblichen Erdbebenrisiko für die Ballungszentren in den Ländern Syrien, Libanon, Palästina, Jordanien und Israel führt. Eine Vielzahl massiver, zerstörerischer Erdbeben hat sich in diesem Raum in den letzten zwei Jahrtausenden ereignet. Ihre Wiederholungsrate zeigt Anzeichen für eine zeitliche Abhängigkeit, insbesondere wenn lange Zeiträume in Betracht gezogen werden. Die Berücksichtigung der zeitlichen Abhängigkeit des Auftretens von Erdbeben ist für eine realistische seismische Gefährdungseinschätzung von großer Bedeutung. Ziel der vorliegenden Arbeit ist es, anhand des zeitabhängigen Auftretens von Erdbeben eine robuste wahrscheinlichkeitstheoretische seismische Gefährdungseinschätzung am Beispiel der DSFZ zu entwickeln. Mittels dieser Methode soll die zeitliche Abhängigkeit des Auftretens von großen Erdbeben (Mw ≥ 6) untersucht und somit eine Gefährdungseinschätzung für das Untersuchungsgebiet getroffen werden. Primär gilt es zu prüfen, ob das Auftreten von großen Erdbeben tatsächlich einer zeitlichen Abhängigkeit unterliegt und wenn ja, inwiefern diese bestimmt werden kann. Zu diesem Zweck werden insgesamt vier zeitabhängige statistische Verteilungen (Weibull, Gamma, Lognormal und Brownian Passage Time (BPT)) sowie die zeitunabhängige Exponentialverteilung (Poisson-Prozess) getestet. Zur Abschätzung der jeweiligen Modellparameter wird eine modifizierte Methode der gewichteten Maximum-Likelihood-Schätzung (MLE) verwendet. Um einzuschätzen, ob die Wiederholungsrate von Erdbeben einer unimodalen oder multimodalen Form folgt, wird ein nichtparametrischer Bootstrap-Test für Multimodalität durchgeführt. Im Falle einer multimodalen Form wird neben der MLE zusätzlich eine Erwartungsmaximierungsmethode (EM) herangezogen. Zur Auswahl des am besten geeigneten Modells wird zum einem das Bayesschen Informationskriterium (BIC) und zum anderen der modifizierte Kolmogorow-Smirnow-Goodness-of-Fit-Test angewendet. Abschließend werden mittels der Bootstrap-Methode die Konfidenzintervalle der geschätzten Parameter berechnet. Als Datengrundlage werden Erdbeben mit Mw ≥ 6 seit dem Jahre 300 n. Chr. herangezogen. Das Untersuchungsgebiet erstreckt sich von 29.5° N bis 37° N und umfasst ein ca. 40 km breites Gebiet entlang der DSFZ. Aufgrund der seismotektonischen Situation im Untersuchungsgebiet wird zwischen einer südlichen, zentralen und nördlichen Subzone unterschieden. Dabei kann die südliche Subzone aus Mangel an Daten nicht für die Analysen herangezogen werden. Die Ergebnisse für die zentrale Subzone zeigen keinen signifikanten multimodalen Verlauf der Wiederholungsrate von Erdbeben. Des Weiteren ist kein signifikanter Unterschied zwischen den zeitabhängigen und dem zeitunabhängigem Modell zu verzeichnen. Da das zeitunabhängige Modell vergleichsweise einfach interpretierbar ist, wird die Wiederholungsrate von Erdbeben in dieser Subzone unter Annahme der Exponentialverteilungs-Hypothese abgeschätzt. Sie wird demnach als zeitunabhängig betrachtet und beträgt 9.72 * 10-3 Erdbeben (mit Mw ≥ 6) pro Jahr. Einen besonderen Fall stellt die nördliche Subzone dar. In diesem Gebiet tritt im Durchschnitt alle 51 Jahre ein massives Erdbeben (Mw ≥ 6) auf. Das letzte Erdbeben dieser Größe ereignete sich 1872 und liegt somit bereits 137 Jahre zurück. Somit ist in diesem Gebiet ein Erdbeben dieser Stärke überfällig. Im statistischen Mittel liegt die Zeit zwischen zwei Erdbeben zu 96% unter 137 Jahren. Zudem wird eine deutliche zeitliche Abhängigkeit der Erdbeben-Wiederauftretensrate durch die Ergebnisse der in der Arbeit neu entwickelten statistischen Verfahren bestätigt. Dabei ist festzustellen, dass die Wiederholungsrate insbesondere kurz nach einem Erdbeben eine sehr hohe zeitliche Abhängigkeit aufweist. Am besten repräsentiert werden die seismischen Bedingungen in der genannten Subzone durch ein bi-modales Weibull-Weibull-Modell. Die Wiederholungsrate ist eine glatte Zeitfunktion, welche zwei Häufungen von Datenpunkten in der Zeit nach dem Erdbeben zeigt. Dabei umfasst die erste Häufung einen Zeitraum von 80 Jahren, ausgehend vom Zeitpunkt des jeweiligen Bebens. Innerhalb dieser Zeitspanne ist die Wiederholungsrate extrem zeitabhängig. Die Wiederholungsrate direkt nach einem Beben ist sehr niedrig und steigert sich in den folgenden 10 Jahren erheblich bis zu einem Maximum von 0.024 Erdbeben/Jahr. Anschließend sinkt die Rate und erreicht ihr Minimum nach weiteren 70 Jahren mit 0.0145 Erdbeben/Jahr. An dieses Minimum schließt sich die zweite Häufung von Daten an, dessen Dauer abhängig von der Erdbebenwiederholungszeit ist. Innerhalb dieses Zeitfensters nimmt die Erdbeben-Wiederauftretensrate annähernd konstant um 0.015 Erdbeben/Jahr zu. Diese Ergebnisse bilden die Grundlage für eine zeitabhängige probabilistische seismische Gefährdungseinschätzung (PSHA) für die seismische Quellregion, die den nördlichen Raum der DSFZ umfasst. / The seismicity of the Dead Sea fault zone (DSFZ) during the last two millennia is characterized by a number of damaging and partly devastating earthquakes. These events pose a considerable seismic hazard and seismic risk to Syria, Lebanon, Palestine, Jordan, and Israel. The occurrence rates for large earthquakes along the DSFZ show indications to temporal changes in the long-term view. The aim of this thesis is to find out, if the occurrence rates of large earthquakes (Mw ≥ 6) in different parts of the DSFZ are time-dependent and how. The results are applied to probabilistic seismic hazard assessments (PSHA) in the DSFZ and neighboring areas. Therefore, four time-dependent statistical models (distributions), including Weibull, Gamma, Lognormal and Brownian Passage Time (BPT), are applied beside the exponential distribution (Poisson process) as the classical time-independent model. In order to make sure, if the earthquake occurrence rate follows a unimodal or a multimodal form, a nonparametric bootstrap test of multimodality has been done. A modified method of weighted Maximum Likelihood Estimation (MLE) is applied to estimate the parameters of the models. For the multimodal cases, an Expectation Maximization (EM) method is used in addition to the MLE method. The selection of the best model is done by two methods; the Bayesian Information Criterion (BIC) as well as a modified Kolmogorov-Smirnov goodness-of-fit test. Finally, the confidence intervals of the estimated parameters corresponding to the candidate models are calculated, using the bootstrap confidence sets. In this thesis, earthquakes with Mw ≥ 6 along the DSFZ, with a width of about 20 km and inside 29.5° ≤ latitude ≤ 37° are considered as the dataset. The completeness of this dataset is calculated since 300 A.D. The DSFZ has been divided into three sub zones; the southern, the central and the northern sub zone respectively. The central and the northern sub zones have been investigated but not the southern sub zone, because of the lack of sufficient data. The results of the thesis for the central part of the DSFZ show that the earthquake occurrence rate does not significantly pursue a multimodal form. There is also no considerable difference between the time-dependent and time-independent models. Since the time-independent model is easier to interpret, the earthquake occurrence rate in this sub zone has been estimated under the exponential distribution assumption (Poisson process) and will be considered as time-independent with the amount of 9.72 * 10-3 events/year. The northern part of the DSFZ is a special case, where the last earthquake has occurred in 1872 (about 137 years ago). However, the mean recurrence time of Mw ≥ 6 events in this area is about 51 years. Moreover, about 96 percent of the observed earthquake inter-event times (the time between two successive earthquakes) in the dataset regarding to this sub zone are smaller than 137 years. Therefore, it is a zone with an overdue earthquake. The results for this sub zone verify that the earthquake occurrence rate is strongly time-dependent, especially shortly after an earthquake occurrence. A bimodal Weibull-Weibull model has been selected as the best fit for this sub zone. The earthquake occurrence rate, corresponding to the selected model, is a smooth function of time and reveals two clusters within the time after an earthquake occurrence. The first cluster begins right after an earthquake occurrence, lasts about 80 years, and is explicitly time-dependent. The occurrence rate, regarding to this cluster, is considerably lower right after an earthquake occurrence, increases strongly during the following ten years and reaches its maximum about 0.024 events/year, then decreases over the next 70 years to its minimum about 0.0145 events/year. The second cluster begins 80 years after an earthquake occurrence and lasts until the next earthquake occurs. The earthquake occurrence rate, corresponding to this cluster, increases extremely slowly, such as it can be considered as an almost constant rate about 0.015 events/year. The results are applied to calculate the time-dependent PSHA in the northern part of the DSFZ and neighbouring areas.

Presented in this thesis are some basic concepts and applications of seismic hazard analysis and the elements that influence the amplitude and geometric attenuation of earthquake ground motion. This thesis centers on the identification of the styles of failure, focal mechanisms, and the state of regional stress in the study area. Seismic hazard is a complex problem often involving considerable uncertainties. Therefore it is reasonable to consider different seismic hazard analysis approaches in order to as robustly as possible define zones of different levels of hazard. With the aim of characterizing and quantifying hazard in the east African region of Eritrea and its surroundings, a study is included in the thesis presenting hazard maps constructed using two non-parametric probabilistic seismic hazard analysis (PSHA) approaches. Peak ground acceleration (PGA) values for 10% probability of exceedence in 50 years are computed at given grid points for the whole selected area and results from both methods are compared. Other aspects addressed in the thesis include the determination of source parameters of selected earthquakes that occur in the Afar region. The styles of faulting, the mechanisms involved during the rupture process and the states of stress along the major tectonic features are also highlighted. Source parameters for selected events in the region were re-evaluated and improved solutions obtained. An aftershock sequence in the Hengill volcanic area in SW Iceland, following the major event that occurred on June 4, 1998, was used to investigate improved methodologies for moment tensor using a relative approach. The sensitive and spatially dense seismic network in this area reveals large sets of clustered events allowing the power of the new methodology to be demonstrated and providing greater insight into the tectonic implications of the activity in the area.

Since 1976, the General Directorate of Disaster Affairs of Turkey has deployed several strong-motion accelerographs at selected sites. Within the framework of the project entitled Compilation of National Strong Ground Motion Database in Accordance with International Standards, initiated in 2006, site conditions at a total of 153 strong-motion sites were investigated within the uppermost 30 m depth through boreholes including Standard Penetration Testing and surface seismics by means of Multi-channel Analysis of Surface Waves (MASW). In this study, firstly, the assessment of the site characterization was held by making use NEHRP Provisions, EC-8 and Turkish Seismic Design Code. The corrected penetration resistances are calculated and observed how it affects the classification. In addition, the consistency of site classes obtained from either penetration resistance or shear wave velocity criteria is examined. Also the consistency of the boundaries of the site classes in terms of shear wave velocity and penetration resistance data pairs are investigated. Secondly, the liquefaction potential of these sites is examined. Thirdly and finally, the shear wave velocity profiles obtained from MASW technique are contrasted to other seismic tests.

The purpose of this study is to assess the engineering geological and geotechnical characteristics and to perform seismic hazard studies of the Upper Pliocene to Quaternary (Plio-Quaternary) deposits located towards the north of Ankara through surface wave testing methods. Based on a general engineering geological and seismic site characterization studies, site classification systems are assigned in seismic hazard assessments. The objective of the research is to determine the regional and local seismic soil conditions (i.e., shear wave velocities, soil predominant periods and soil amplification factors) and to characterize the soil profile of the sites in this region by the help of surface geophysical methods. These studies have been supported by engineering geological and geotechnical field studies carried out prior to and during this study. By integrating these studies, local soil conditions and dynamic soil characteristics for the study area have been assessed by detailed soil characterization in the region. As a result, seismic hazard assessments have been performed for &Ccedil / ubuk and its close vicinity with the aid of Geographical Information Systems (GIS) through establishing seismic characterization and local soil conditions of the area.

Efficiency of probabilistic seismic hazard analysis mainly depends on the individual successes of its complementing components / such as source characterization and ground motion intensity prediction. This study contributes to major components of the seismic hazard workflow including magnitude &ndash / rupture dimension scaling relationships, and ground motion intensity prediction. The study includes revised independent models for predicting rupture dimensions in shallow crustal zones, accompanied by proposals for geometrically compatible rupture area-length-width models which satisfy the rectangular rupture geometry assumption. Second main part of the study focuses on developing a new ground motion prediction model using data from Turkish strong ground motion database. The series of efforts include, i) compilation and processing of a strong motion dataset, ii) quantifying parameter uncertainties of predictive parameters such as magnitude and source to site distance / and predicted accelerations due to uncertainty in site conditions and response, as well as uncertainty due to random orientation of the sensor, iii) developing a ground response model as a continuous function of peak ground acceleration and shear wave velocity, and finally, iv) removing bias in predictions due to uneven sampling of the dataset. Auxiliary components of the study include a systematic approach to source characterization problem, with products ranging from description of systematically idealized and documented seismogenic faults in Anatolia, to delineation, magnitude-recurrence parameterization, and selection of maximum magnitude earthquakes. Last stage of the study covers the development of a custom computer code for probabilistic seismic hazard assessment which meets the demands of modern state of practice.

Future seismic losses including the physical, economic and social ones as well as casualties concern a wide range of authorities varying from geophysical and earthquake engineers, physical and economic planners to insurance companies. As its many components involve inherent uncertainties, a probabilistic approach is required to estimate seismic losses. This study aims to propose a probabilistic method for estimating seismic losses, and to predict the potential seismic loss for the residential buildings for a selected district in Bursa, which is a highly industrialized city in Northwestern Turkey. To verify the methodology against a past large event, loss estimations are initially performed for a district in D&uuml / zce, and the method is calibrated with loss data from the 12 November 1999 D&uuml / zce Earthquake. The main components of the proposed loss model are seismic hazard, building vulnerability functions and loss as a function of damage states of buildings. To quantify the regional hazard, a probabilistic seismic hazard assessment approach is adopted. For different types of building structures, probability of exceeding predefined damage states for a given hazard level is determined using appropriate fragility curve sets. The casualty model for a given damage level considers the occupancy type, population of the building, occupancy at the time of earthquake occurrence, number of trapped occupants in the collapse, injury distribution at collapse and mortality post collapse. Economic loss is calculated by multiplying mean damage ratio with the total cost of initial construction. The proposed loss model combines these input components within a conditional probability approach. The results are expressed in terms of expected loss and losses caused by events with different return periods.

The seismic response of steel monopole wind turbine towers is investigated and their risk is assessed in the Canadian seismic environment. This topic is of concern as wind turbines are increasingly being installed in seismic areas and design codes do not clearly address this aspect of design. An implicit finite element model of a 1.65MW tower was developed and validated. Incremental dynamic analysis was carried out to evaluate its behaviour under seismic excitation, to define several damage states, and to develop a framework for determining its probability of damage. This framework was implemented in two Canadian locations, where the risk was found to be low for the seismic hazard level prescribed for buildings. However, the design of wind turbine towers is subject to change, as is the design spectrum. Thus, a methodology is outlined to thoroughly investigate the probability of reaching predetermined damage states under seismic loading for future considerations.

The seismic response of steel monopole wind turbine towers is investigated and their risk is assessed in the Canadian seismic environment. This topic is of concern as wind turbines are increasingly being installed in seismic areas and design codes do not clearly address this aspect of design. An implicit finite element model of a 1.65MW tower was developed and validated. Incremental dynamic analysis was carried out to evaluate its behaviour under seismic excitation, to define several damage states, and to develop a framework for determining its probability of damage. This framework was implemented in two Canadian locations, where the risk was found to be low for the seismic hazard level prescribed for buildings. However, the design of wind turbine towers is subject to change, as is the design spectrum. Thus, a methodology is outlined to thoroughly investigate the probability of reaching predetermined damage states under seismic loading for future considerations.

The purpose of this study is to assess the engineering geological and geotechnical characteristics and to perform seismic hazard studies of the Upper Pliocene and Quaternary deposits located towards the west of Ankara. Based on a general engineering geological and seismic characterization of the site, site classification systems are assigned for seismic hazard assessment studies. The objective of the research is to determine the regional and local seismic soil conditions, predominant periods and ground amplifications, and to idealize the soil profile of the sites by the aid of surface geophysical methods. These studies are combined and integrated with the geotechnical database from a variety of in-situ and laboratory studies that are compiled from present and previous studies regarding the project area and then transferred to an analytical environment for creating relevant information for our site. Then, engineering geological and geotechnical seismic characterization along with seismic zoning map preperation is accomplished. Finally, based on a general engineering geological and geotechnical site characterization, site classification systems are assigned to account for site effects in seismic hazard assessments along with the assessment of mitigation and remediation of seismic hazards.

Submitted by Marlon Pirchiner (marlon.pirchiner.work@gmail.com) on 2014-09-09T12:41:58Z No. of bitstreams: 1 dissertacao_biblioteca.pdf: 20168048 bytes, checksum: 06f8b607a56d91eecc737ff55933780a (MD5) / Approved for entry into archive by Janete de Oliveira Feitosa (janete.feitosa@fgv.br) on 2015-09-09T18:43:32Z (GMT) No. of bitstreams: 1 dissertacao_biblioteca.pdf: 20168048 bytes, checksum: 06f8b607a56d91eecc737ff55933780a (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2015-09-11T12:21:49Z (GMT) No. of bitstreams: 1 dissertacao_biblioteca.pdf: 20168048 bytes, checksum: 06f8b607a56d91eecc737ff55933780a (MD5) / Made available in DSpace on 2015-09-11T12:22:02Z (GMT). No. of bitstreams: 1 dissertacao_biblioteca.pdf: 20168048 bytes, checksum: 06f8b607a56d91eecc737ff55933780a (MD5) Previous issue date: 2014-07-15 / Seismic risk assesment is crucial to make better decisions about engineering structures and loss mitigation. It involves, mainly, the evaluation of seismic hazard. Seismic hazard assesment is the computation of probability which the level of some ground motion intensity measure, in a given site, which, in some time window, will be exceeded. Depending on geological and tectonic complexity, the seismic hazard evaluation becomes more sofisticated. At sites with low seismicity, which is the brazilian case, the relative (geolo- gically) low observation time and the lack of earthquake and tectonic information, increases the uncertainties and makes more difficult the standard analysis, which in general, consider expert opinions, to characterize the seismicity into disjoint zones. This text discusses some smoothing seismicity techniques and their theoretical foundati- ons as alternative methods for seismicity characterization. Next, the methods are exemplified in the brazilian context. / A avaliação de risco sísmico, fundamental para as decisões sobre as estruturas de obras de engenharia e mitigação de perdas, envolve fundamentalmente a análise de ameaça sísmica. Calcular a ameaça sísmica é o mesmo que calcular a probabilidade de que certo nível de determinada medida de intensidade em certo local durante um certo tempo seja excedido. Dependendo da complexidade da atividade geológica essas estimativas podem ser bas- tante sofisticadas. Em locais com baixa sismicidade, como é o caso do Brasil, o pouco tempo (geológico) de observação e a pouca quantidade de informação são fontes de muitas incer- tezas e dificuldade de análise pelos métodos mais clássicos e conhecidos que geralmente consideram, através de opiniões de especialistas, determinadas zonas sísmicas. Serão discutidas algumas técnicas de suavização e seus fundamentos como métodos al- ternativos ao zoneamento, em seguida se exemplifica suas aplicações no caso brasileiro.