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ANALYSIS OF ARIAS INTENSITY OF EARTHQUAKE DATA USING SUPPORT VECTOR MACHINEAdhikari, Nation 01 August 2022 (has links)
In this thesis, a support vector machine (SVM) is used to develop a model to predict Arias Intensity. Arias Intensity is a measure of the strength of ground motions that considers both the amplitude and the duration of ground motions. In this research, a subset of the database from the “Next Generation and the duration of Ground-Motion Attenuation Models” project was used as the training data. The data includes 3525 ground motion records from 175 earthquakes. This research provides the assessment of historical earthquakes using arias intensity data. Support vector machine uses a Kernel function to transform the data into a high dimensional space where relationships between the variables can be efficiently described using simpler models. In this research, after testing several kernel functions, a Gaussian Kernel was selected for the predictive model. The resulting model uses magnitude, epicentral distance, and the shear wave velocity as the predictor of Arias Intensity.
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Seismic performance of a bridge subjected to far-field ground motions by a Mw 9.0 earthquake and near-field ground motions by a Mw 6.9 earthquakeGoto, Reina January 2012 (has links)
In the last two decades, two major earthquakes have occurred in Japan: the 1995 Kobe earthquake and the 2011 Great East Japan earthquake. In the 2011 Great East Japan earthquake, many bridge structures were destroyed by the tsunamis, but it is interesting to study the ground motion induced damage and also how this earthquake differed from the one in 1995. In this thesis, the seismic response of a bridge designed according to the current Japanese Design Specifications was evaluated when it is subjected to near-field ground motions recorded during the 1995 Kobe earthquake and far-field ground motions recorded during the 2011 Great East Japan earthquake. For this purpose, a series of nonlinear dynamic response analysis was conducted and the seismic performance of the bridge was verified in terms of its displacement and ductility demand. It was found from the dynamic response analysis that the seismic response of the target bridge when subjected to the ground motions from the 2011 Great East Japan earthquake was smaller than during the 1995 Kobe earthquake. Although the ground motions from the 2011 Great East Japan earthquake were very strong, they were not as strong as the ground motions from the 1995 Kobe earthquake. The results obtained in this thesis clarify the validity of the Type I and Type II design ground motions. The target bridge used in this thesis was designed according to the post-1990 design specifications and showed limited nonlinear response when subjected to the different ground motions which shows how efficient the enhancement of the seismic performance of bridges has been since the 1990’s.
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EFFECT OF SIMULTANEOUS APPLICATION OF THE TWO HORIZONTAL ORTHOGONAL GROUND MOTION COMPONENTS ON THE SEISMIC BEHAVIOR OF BUILDINGS (CASE OF FOUR-STORY STEEL FRAME)KISEKINI, JOEL MONDO 01 May 2022 (has links)
Joel Mondo Kisekini, for the Master of Science degree in Civil Engineering, presented on March 25, 2022, at Southern Illinois University Carbondale.TITLE: EFFECT OF SIMULTANEOUS APPLICATION OF THE TWO HORIZONTAL ORTHOGONAL GROUND MOTION COMPONENTS ON THE SEISMIC BEHAVIOR OF BUILDINGSMAJOR PROFESSOR: Dr. JALE TEZCAN During an earthquake, buildings are simultaneously excited by two horizontal and one vertical ground motion components. Modern seismic codes and guidelines such as ASCE/SEI 41-06 (Seismic rehabilitation of existing buildings, American Society of Civil Engineers), EUROCODE 8 (1998-1) (Design provisions for earthquake resistance of structures, European Committee for Standardization, 2003), FEMA 356 (Prestandard and Commentary for Seismic Rehabilitation of the Buildings) and FEMA P-2082 (NEHRP Recommended Seismic Provisions for new buildings and other structures) require the consideration of the effects of two horizontal orthogonal ground motions in seismic design of buildings. Therefore, the main objective of this study is to evaluate the simultaneous effect of two horizontal orthogonal ground motion components to seismic behavior of buildings. A four-story steel frame is modeled, and it is subjected to a set of twenty ground motion pairs recorded distances between x and y kilometer from epicenter. Three methods for combining peak response to individual component of ground motions is used to estimate the displacement responses. The combination rules used in this present study are 30%, SRSS, and 20%. The response of the four-story steel frame is investigated within the context of linear response history analysis and the results are compared to the peak responses obtained from time history analyses under bidirectional and unidirectional ground motion. The structural response includes the following parameters: nodal displacements and the critical angle of excitation. The output results showed that the maximum response under two components was, on average, 23 % more than the maximum response under a single component, and the two horizontal orthogonal seismic excitations increased the structure displacement response compared to unidirectional excitation.
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EFFECT OF BUILDING ORIENTATION ON STRUCTURAL RESPONSE OF REINFORCED CONCRETE MOMENT RESISTING FRAME STRUCTURESParsa, Amanullah 01 May 2020 (has links)
In time history analysis of structures, the geometric mean of two orthogonal horizontal components of ground motion in the as-recorded direction of sensors, have been used as measure of ground motion intensity prior to the 2009 NEHRP provision. The 2009 NEHRP Provisions and accordingly the seismic design provisions of the ASCE/SEI 7-10, modified the definition of ground motion intensity measure from geometric mean to the maximum direction ground motion, corresponding to the direction that results in peak response of the oscillator. Maximum direction response spectra are assumed to envelope the range of maximum possible responses over all nonredundant rotation angles. Two assumptions are made in the use maximum ground motion as the intensity measure: (1) the structure’s strength and stiffness properties are identical in all directions and (2) azimuth of the maximum spectral acceleration coincides with the one of the principal axes of the structure. The implications of these assumptions are examined in this study, using 3D computer models of multi-story structures having symmetric and asymmetric layouts and elastic vibration period of 0.2 second and 1.0 second subjected to a set of 25 ground-motion pairs recorded at a distance of more than 20 km from the fault. The influence of the ground-motion rotation angle on structural response (here lateral displacement and story drift) is examined to form benchmarks for evaluating the use of the maximum direction (MD) ground motions. The results of this study suggest that while MD ground motions do not always result in largest structural response, they tend to produce larger response than the as-recorded ground motions. On the other hand, more research on non-linear seismic time history analysis is recommended, especially for asymmetric layout plan buildings.
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Απόκριση του μοντέλου ολίσθησης Newmark σε σεισμικές διεγέρσεις εγγύς πεδίουΠράπα, Ευγενία 05 February 2015 (has links)
Μεγάλος αριθμός έργων πολιτικού μηχανικού αναπτύσσουν μηχανισμούς ολίσθησης. Η ευστάθεια πρανούς που καταπονείται από σεισμικές διεγέρσεις είναι ένα πρόβλημα που απασχόλησε πληθώρα μελετητών κατά την διάρκεια των χρόνων και οδήγησε στην ανάπτυξη διαφόρων μεθόδων για την εκτίμηση των μόνιμων παραμορφώσεων με το πέρας της κίνησης. Σκοπός της παρούσας εργασίας είναι να μελετήσει το φαινόμενο της ασύμμετρης ολίσθησης πρανούς προσομοιώνοντάς το, με ένα μοντέλο που αναπτύχθηκε το 1965 από τον Newmark και να καταδείξει το μέγεθος των μετατοπίσεων που αναπτύσσονται , το πώς η πολικότητα του σεισμού επηρεάζει την συμπεριφορά του πρανούς καθώς και την περεταίρω μελέτη που επιβάλλεται να διεξαχθεί. Αναπτύσσεται αναλυτικά η λογική της κίνησης καθώς και οι τρόποι προσέγγισης του προβλήματος, μία λύση κλειστής μορφής και μία με το μοντέλο Bouc- Wen, διερευνούνται οι παράμετροι που επηρεάζουν το πρόβλημα και τέλος παρατίθενται αφενός τα αποτελέσματα συγκριτικά με αυτά της βιβλιογραφίας και αφετέρου των αναλύσεων πλήθους σεισμικών διεγέρσεων εγγύς πεδίου. / Numerous civil engineer’s applications develop sliding mechanisms. Slope’s stability under seismic excitations is a problem that was investigated by several researchers in recent years and led to the development of various methods for the estimation of permanent displacement by the end of the motion. The current study examines the slope’s asymmetric sliding by Newmark’s analogue, calculates the residual slippage, shows how polarity affects slope’s behavior and suggests further analysis. The concept of behavior is analysed thoroughly, the two approaches of the problem are presented (a closed form solution and a Bouc-Wen Model analysis), the parameters of the problem are investigated and eventually, a literature comparison and analysis results are listed.
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Existing Performance and Effect of Retrofit of High-Rise Steel Buildings Subjected to Long-Period Ground Motions / 長周期地震動を受ける高層鋼構造建物がもつ耐震性能評価と耐震補強効果Chung, YuLin 23 March 2010 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第15367号 / 工博第3246号 / 新制||工||1488(附属図書館) / 27845 / 京都大学大学院工学研究科建築学専攻 / (主査)教授 中島 正愛, 教授 林 康裕, 教授 吹田 啓一郎 / 学位規則第4条第1項該当
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Comparative Study of Seismic Performance of Reinforced Concrete Buildings designed in accordance with the Seismic Provisions of ASCE 7-10 and IS 1893-2002Jadhav, Sagar M. 14 October 2013 (has links)
No description available.
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Development of a Comprehensive Linear Response History Analysis Procedure for Seismic Load AnalysisTola, Adrian Patricio 11 March 2011 (has links)
This thesis reviews the parameters required to perform linear response history analysis according to Chapter 16 of the American Standard ASCE 7-10. A careful analysis is presented about the selection of ground motions using real records and using artificial records generated such that their response spectrum matches with a defined target spectrum; three different techniques are studied for the generation of these artificial records. Also, this document revises the scaling of ground motion techniques in the American Standard ASCE-7 as well as in other seismic codes. It presents a detailed analysis of the variables influencing the scaling of ground motions, and it suggests a new scaling technique for linear response history analysis. The assumptions made establishing the flexibility of the diaphragms are also analyzed as well as dynamic methods to include accidental torsion when doing a linear response history analysis. Other modeling issues such as the orientation of the ground motion axis, scaling of element forces and displacements, orthogonal loading, solution techniques, P-Delta effects, modeling of the basement, and calculation of drifts are also studied in the context of linear response history analysis. The thesis concludes with suggested code language for linear response history analysis intended to be considered in future editions of the American Standard ASCE 7. / Master of Science
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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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Dynamic Pull Analysis For Estimating The Seismic ResponseDegirmenci, Can 01 November 2006 (has links) (PDF)
The analysis procedures employed in earthquake engineering can be classified as linear static, linear dynamic, nonlinear static and nonlinear dynamic. Linear procedures are usually referred to as force controlled and require less analysis time and less computational effort. On the other hand, nonlinear procedures are referred to as deformation controlled and they are more reliable in characterizing the seismic performance of buildings. However, there is still a great deal of unknowns for nonlinear procedures, especially in modelling the reinforced concrete structures.
Turkey ranks high among all countries that have suffered losses of life and property due to earthquakes over many centuries. These casualties indicate that, most regions of the country are under seismic risk of strong ground motion. In addition to this phenomenon, recent studies have demonstrated that near fault ground motions are more destructive than far-fault ones on structures and these effects can not be captured effectively by recent nonlinear static procedures.
The main objective of this study is developing a simple nonlinear dynamic analysis procedure which is named as &ldquo / Dynamic Pull Analysis&rdquo / for estimating the seismic response of multi degree of freedom (MDOF) systems. The method is tested on a six-story reinforced concrete frame and a twelve-story reinforced concrete frame that are designed according to the regulations of TS-500 (2000) and TEC (1997).
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