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[en] STATISTIC EVALUATION OF THE METODOLOGY FOR DETERMINATION OF UNIFORMLY PROBABLE RESPONSE ESPECTRA / [pt] AVALIAÇÃO ESTATÍSTICA DE METODOLOGIA PARA DETERMINAÇÃO DE ESPECTROS DE RESPOSTA DE PROJETO UNIFORMEMENTE PROVÁVEISMARCOS POZZATO FIGUEIREDO 09 June 2004 (has links)
[pt] Apresenta-se uma avaliação numérica estatística de
metodologia para obtenção de espectros de resposta
uniformemente prováveis, ERUP, Diniz [2], fundamentada na
determinação da distribuição de probabilidade dos valores
extremos da resposta de um sistema com um grau de
liberdade, submetido a movimentos de terreno oriundos de
terremotos. Tais movimentos são caracterizados por funções
de densidade de espectro de potência, cada uma das quais
representando uma família de sismos. Para tal, utiliza-se
uma função densidade de espectro de potência, FDEP, como
base à avaliação. A partir da FDEP, são gerados
acelerogramas artificiais utilizando o programa SISMOSINV,
desenvolvido internamente ao trabalho. Empregam-se estes
acelerogramas para obterem-se espectros de resposta,
utilizando o programa SAP2000. Os ERUP são então
calculados, utilizando as distribuições de probabilidade
acumulada dos valores espectrais obtidas por técnicas
adequadas de estatística, implementadas especialmente para
o caso. Efetua-se a comparação entre os ERUP obtidos
estatisticamente e os produzidos pela metodologia
probabilística e são formuladas conclusões e recomendações
sobre os limites de emprego desta última. Comparam-se,
ainda, os ERUP obtidos pelo procedimento estatístico com o
espectro de resposta de projeto recomendado pela USNRC [13]
para avaliar o compromisso entre estes espectro e a FDEPo
da USNRC [1]. / [en] One presents a statistic evaluation of Diniz metodology
[2], to obtain uniformly probable response espectra, UPRS,
based on the determination of the probability
distribuition of the response extreme values of a single-
degree of freedom structure, under a ground movement caused
by an earthquake. Such movements are characterized by power
spectrum density functions, each one of them representing a
family of seismic events. On this way, one considers a
power spectral density function, PSD, as a basis for the
evaluation. Using the PSD, one generates artificial ground
acceleration functions with the program SISMOSINV,
developed within this work. From these artificial ground
acceleration functions one obtains the response spectra
with the SAP2000 program. Then, the UPRS are calculated,
using the spectral value distributions, by adequate
statistical techniques, implemented for the case. One then
compares the UPRS obtained statiscally with those obtained
by the probabilistic methodology and conclusions and
recommendations are formulated concerning the applicability
limits of this methodology One still compares the
statiscally obtained UPRS with the design response spectrum
prescribed by the USNRC [13] to evaluate the compromise
between this spectrum and the target power spectral density
function, TPSD, prescribed by the USNRC [1].
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Influence de l'hétérogénéité géologique et mécanique sur la réponse des sols multicouches / Influence of the geological and mechanical heterogeneity on multilayered soils responseBadaoui, M'Hammed 30 March 2008 (has links)
Dans cette thèse nous nous sommes intéressés à établir une formulation probabiliste pour l’analyse du comportement d’un sol multicouche avec des caractéristiques aléatoires. Deux grands axes sont traités : ?la consolidation primaire et ?la réponse sismique des sols multicouches ayant des caractéristiques aléatoires. Nous utilisons les simulations de Monte Carlo associées à des méthodes semi-analytiques adaptées aux sols multicouches avec une stratification horizontale. Nous avons aussi comparés les résultats obtenus à partir de cette formulation à ceux fournis par les règlements parasismiques suivants : RPA 99 (version 2003), UBC 97 et l’EC8. Cette étude a montré que les valeurs maximales des forces de cisaillement à la base des bâtiments variaient substantiellement en fonction de la variation de la hauteur du profil de sol ainsi que de son hétérogénéité pouvant atteindre un rapport relatif de l’ordre de 3 dans les cas les plus défavorables. Ce rapport peut également être inférieur à 1 conduisant à des structures moins économiques / In this thesis we are interested to establish a probabilistic formulation for the behavior analysis of a multilayered soil with random characteristics. Two main axes are treated: ?primary consolidation and ?seismic response of multilayered soils with uncertain characteristics. We use Monte Carlo simulations associated with semi-analytical methods adapted for the multilayered soils with horizontal stratification. We have also compared the results obtained from this formulation with those provided by the following seismic codes: RPA 99 (version 2003), UBC 97 and EC8. This study showed that the maximum values of the shear forces at the base of the buildings vary substantially according to the variation of the soil profile height as well as its heterogeneity which can reach a relative ratio of about 3 in the extreme cases. This ratio can also be lower than 1 leading to less economic structures
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Análise estrutural dinâmica de um vaso de pressão (reator PWR) utilizando o método DDAM. / Dynamic strutural analisys of a pressure vessel (PWR reactor) using DDAM method.Maruyama, Fábio Massatoshi 30 November 2012 (has links)
O objetivo deste trabalho é verificar a aplicação do Dynamic Design Analysis Method DDAM na análise de estruturas submetidas a carregamentos de choque. Esse método foi desenvolvido pela Marinha Norte Americana e se propõe a estimar esforços inercias provenientes das respostas de equipamentos de bordo, sejam de navios ou submarinos, a cargas impulsivas, mais precisamente, ondas de choque submarinas. Para a compreensão plena dessa metodologia, foi necessário um estudo sobre vibrações e espectros de resposta, tópicos teóricos que fundamentam esse procedimento. Devido à escassez de informações divulgadas por se tratar de conteúdo militar, foi realizado um estudo de caso para uma estrutura simples, uma viga engastada e seus resultados foram comparados com um prévio trabalho publicado. Com isso, foi possível a aplicação do DDAM em uma estrutura mais complexa como o vaso do reator nuclear do tipo PWR de um submarino, ainda que em um modelo simplificado desse equipamento. No entanto, os resultados mostraram a validade do uso do DDAM na análise estrutural dinâmica de equipamentos de uma maneira qualitativa. / The main purpose of this dissertation is to verify the use of the Dynamic Design Analysis Method DDAM in the study of structures subjected to shock loadings. This method was developed by the U.S. Navy and is intended to estimate inertial forces resultant from the response of shipboard equipment, from surface ships or submarines, due to impulsive loads or, more precisely, underwater pressure shock waves. To fully comprehend this method, it was necessary to acknowledge fundamentals of dynamics of structures like free vibrations, response spectrum analysis correlated topics. And due to lack of public information since it is a military technology, a case study of a cantilever beam was done with its results compared to a previous published paper. Then, the DDAM was applied to a more complex structure a PWR nuclear reactor vase simplified model, in order to show the effectiveness of the method in dynamic structural analysis.
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A Proposed Ground Motion Selection And Scaling Procedure For Structural SystemsAy, Bekir Ozer 01 December 2012 (has links) (PDF)
This study presents a ground-motion selection and scaling procedure that preserves the inherent uncertainty in the modified recordings. The proposed procedure provides a set of scaled ground-motion records to be used in the response estimation of structural systems for a pre-defined earthquake hazard level. Given a relatively larger ground-motion dataset, the methodology constrains the selection and scaling of the accelerograms to the differences between individual records and corresponding estimations from a representative ground-motion predictive model. The procedure precisely calculates the distribution parameters of linear structural systems whereas it provides estimations of these parameters for nonlinear structural response. Thus this method is not only useful for ground-motion selection and scaling but also for probability based performance assessment studies. The proposed procedure is also capable of matching with a pre-defined target elastic response spectrum and corresponding variance over a period range. Case studies that compare the performance of the proposed procedure with some other record selection and scaling methods suggest its usefulness for the accurate verification of structural systems and rapid loss estimation studies.
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Seismic Fragility Assessment of Steel Frames in the Central and Eastern United StatesKinali, Kursat 28 March 2007 (has links)
The Central and Eastern United States (CEUS) is a region that is characterized by low frequency-high consequence seismic events such as the New Madrid sequence of 18111812. The infrequent nature of earthquakes in the region has led to a perception that the seismic risk in the area is low, and the current building stock reflects this perception. The majority of steel-framed buildings in the CEUS were designed without regard to seismic loads. Such frames possess limited seismic resistance, and may pose an unacceptable risk if a large earthquake were to occur in the region. A key ingredient of building performance and seismic risk assessment is the fragility, a term that describes the probability of failure to meet a performance objective as a function of demand on the system. The effects of uncertainties on building seismic performance can be displayed by a seismic fragility relationship. This fragility can be used in a conditional scenario-based seismic risk assessment or can be integrated with seismic hazard to obtain an estimate of annual or lifetime risk. The seismic fragility analyses in this study focus on steel frames that are typical of building construction in regions of infrequent seismicity; such frames have received little attention to date in building seismic risk assessment. Current steel building stock in Shelby Co., TN has been represented by five code-compliant model frames with different lateral force-resisting systems, i.e., braced-frames, partially-restrained moment frames and a rigid moment frame. The performance of model frames under certain hazard levels was assessed using fragility curves. Different rehabilitation methods were discussed and applied. Results indicate that PR frames behave better than expected and rehabilitated frames perform quite well even under severe earthquakes.
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Prüfung von Flexitanksystemen mittels Bahnauflaufversuchen unter Berücksichtigung des SchockantwortspektrumsHartwig, Peter 25 March 2014 (has links) (PDF)
Die vorliegende Arbeit befasst sich mit der Weiterentwicklung eines Prüfregelwerks für Flexitanksysteme hinsichtlich des durchzuführenden Bahnauflaufstoßes. Während eines solchen Versuchs wird das Flexitanksystem, bestehend aus einem herkömmlichen Seefrachtcontainer und beladen mit einem wassergefüllten Folientank sowie einiger Zusatzeinrichtungen, auf einem Tragwagen verankert und anschließend einer intensiven Stoßbelastung ausgesetzt. Der Nachweis der Dichtigkeit des Tanks und die Einhaltung diverser Verformungsgrenzwerte am Container entscheiden über den Ausgang des Versuchs. Während die Arbeit auch diese Punkte aufgreift, liegt der eigentliche Schwerpunkt in der Auseinandersetzung mit derjenigen Beurteilungsgröße, welche die Erfüllung der Prüfanforderungen bestimmt.
Derzeit wird dieses Prüfkriterium über eine Beschleunigungsamplitude definiert, was allerdings eine gewisse Unschärfe mit sich bringt. Die Prüfmethodik und ihre Entwicklungsgeschichte, sowie die damit einhergehenden Nachteile werden im Detail erläutert und eine Möglichkeit der Erweiterung des Kriteriums mithilfe des Schockantwortspektrums geboten. Als Beurteilungsgröße für die dynamische Prüfung von Tankcontainern bereits fest etabliert, wird dieses mathematische Analysewerkzeug in allen Einzelheiten vorgestellt und dessen Eignung für die Anwendung im Bahnauflaufstoß für Flexitanksysteme untersucht. Zu diesem Zweck wird ein Simulationsmodell entwickelt, mit dessen Hilfe eine ausführliche Parameteranalyse durchgeführt und deren Ergebnisse Versuchsmessungen gegenübergestellt werden. Die Schlussfolgerungen münden in einem dem Flexitanksystem angepassten Prüfkriterium auf Basis des Schockantwort-spektrums, welches in Form eines Regelwerksentwurfs den entscheidungsberechtigten Gremien vorgeschlagen wird.
Die Inhalte der drei Hauptkapitel der Dissertation können in folgenden Punkten zusammengefasst werden:
Das Flexitanksystem wird vorgestellt, der Auflaufversuch erläutert und diskutiert sowie Versuchsergebnisse präsentiert und nach verschiedenen Gesichtspunkten analysiert.
Das Schockantwortspektrum wird hergeleitet, dessen Charakteristika herausgestellt und deren Anwendung an praktischen Beispielen demonstriert.
Die Eignung des Schockantwortspektrums zur Beurteilung von Auflaufstößen mit Flexitanksystem wird überprüft, die Einflussfaktoren in einer Parameteranalyse durchleuchtet und die Ergebnisse in die Definition eines neuen Prüfkriteriums eingeflochten.
Die Dissertation entstand im Rahmen eines Fördermittelprojekts des Europäischen Sozialfonds und in Kooperation mit der Prüfanlage der TÜV SÜD Rail GmbH in Görlitz.
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Strategy for Selecting Input Ground Motion for Structural Seismic Demand Analysis / Élaboration de Stratégies de Sélection de Signaux Accélérométriques pour le Calcul du Comportement des StructuresIsbiliroglu, Levent 01 March 2018 (has links)
Les signaux accélérométriques enregistrés lors de l’occurrence d’un événement sismique est très large présentent une forte variabilité, par conséquent ils ne sont pas utilisé dans les analyse dynamiques de tenue sismique des structures. En effet, l’utilisation des accélérogrammes réels, pour les analyses dynamiques non linéaires, s’avère couteuse en termes de temps de calcul. La pratique courante prévoit la minimisation (voir suppression) de telle variabilité, mais les conséquences d’une telle opération sur la réponse des structures ne sont pas clairement indiquées. L’étude ci-présente a pour scope la quantification de l’impact des méthodes de sélection qui gardent la variabilité du signal sur les résultats de l’analyse de la réponse des structures (exprimée en termes d’engineering demand parameters EDPs). En particulier les questions suivantes seront investiguées :Quel est le niveau de variabilité des accélérogrammes réels et comment ce niveau est modifié par les techniques couramment utilisées ?Quelle est l’impact de la variabilité sur la réponse de plusieurs types de structures ?Pour un scénario sismique donné, un spectre cible est défini à partir de plusieurs équation de prédiction du mouvement sismique, sélection parmi celles disponibles en littérature. Les accélérogrammes sont sélectionnés à partir de quatre familles d’accélérogrammes, chacune relative à une méthode de modification : réels (enregistrés); mise à l’échelle (multiplication, par un facteur) ; calés aux spectres cibles avec large tolérance ; calés aux spectres cibles dans une plage de tolérance étroite.Chaque jeu de signaux est composé de cinq accélérogrammes et la sélection des signaux est faite en tenant compte de deux sources de variabilité : la variabilité au sein de chaque jeu de données (intraset), et la variabilité entre les différents jeux de données (interset) tous compatibles avec le même spectre cible. Les tests sur les EDPs menés sur les signaux accélérométriques réels mènent à la quantification de la variabilité naturelle (pour le scénario considéré). Les analyses basées sur les signaux réels sont utilisés comme benchmark afin d’évaluer non seulement de combien la distribution des EDPs (en termes de valeur moyenne et variabilité) est réduite par les différentes méthodes testées, mais aussi d’évaluer l’impact des choix de l’équation de prédiction du mouvement, des plages de tolérance, du nombre d’accélérogrammes constituant chaque jeu, du nombre de jeux, de le scope de l’analyse structurale et le modèle de structure.Ce travaille nous conduit à conclure que un seul jeu d’accélérogramme, tel qu’utilisé dans la pratique courante, est insuffisant pour assurer le niveau d’EDPs indépendamment de la méthode de modification utilisés, cela est lié à la variabilité des signaux et entre les jeux d’accélérogrammes. Les signaux réels, compatibles avec le spectre définis pour le scénario sismique, are l’option plus réaliste pour l’analyse dynamique non-linéaire ; si une méthode de modification du signal est nécessaire, la plus adaptées dépend du scope de l’analyse spectrale et du modèle. Le choix de l’équation de prédiction du mouvement sismique utilisée pour définir le spectre cible impacte significativement les caractéristiques des mouvements sismiques et des EDPs. Cette observation ne dépend pas de la stratégie de de modification du signal. / The observed variability is very large among natural earthquake records, which are not consolidated in the engineering applications due to the cost and the duration. In the current practice with the nonlinear dynamic analysis, the input variability is minimized, yet without clear indications of its consequences on the output seismic behavior of structures. The study, herein, aims at quantifying the impact of ground motion selection with large variability on the distribution of engineering demand parameters (EDPs) by investigating the following questions:What is the level of variability in natural and modified ground motions?What is the impact of input variability on the EDPs of various structural types?For a given earthquake scenario, target spectra are defined by ground motion prediction equations (GMPEs). Four ground motion modification and selection methods such as (1) the unscaled earthquake records, (2) the linearly scaled real records, (3) the loosely matched spectrum waveforms, and (4) the tightly matched waveforms are utilized. The tests on the EDPs are performed on a record basis to quantify the natural variability in unscaled earthquake records and the relative changes triggered by the ground motion modifications.Each dataset is composed by five accelerograms; the response spectrum compatible selection is then performed by considering the impact of set variability. The intraset variability relates to the spectral amplitude dispersion in a given set, and the interset variability relates to the existence of multiple sets compatible with the target.The tests on the EDPs are performed on a record basis to quantify the natural variability in unscaled earthquake records and the relative changes triggered by the ground motion modifications. The distributions of EDPs obtained by the modified ground motions are compared to the observed distribution by the unscaled earthquake records as a function of ground motion prediction equations, objective of structural analysis, and structural models.This thesis demonstrates that a single ground motion set, commonly used in the practice, is not sufficient to obtain an assuring level of the EDPs regardless of the GMSM methods, which is due to the record and set variability. The unscaled real records compatible with the scenario are discussed to be the most realistic option to use in the nonlinear dynamic analyses, and the ‘best’ ground motion modification method is demonstrated to be based on the EDP, the objective of the seismic analysis, and the structural model. It is pointed out that the choice of a GMPE can provoke significant differences in the ground motion characteristics and the EDPs, and it can overshadow the differences in the EDPs obtained by the GMSM methods.
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Análise estrutural dinâmica de um vaso de pressão (reator PWR) utilizando o método DDAM. / Dynamic strutural analisys of a pressure vessel (PWR reactor) using DDAM method.Fábio Massatoshi Maruyama 30 November 2012 (has links)
O objetivo deste trabalho é verificar a aplicação do Dynamic Design Analysis Method DDAM na análise de estruturas submetidas a carregamentos de choque. Esse método foi desenvolvido pela Marinha Norte Americana e se propõe a estimar esforços inercias provenientes das respostas de equipamentos de bordo, sejam de navios ou submarinos, a cargas impulsivas, mais precisamente, ondas de choque submarinas. Para a compreensão plena dessa metodologia, foi necessário um estudo sobre vibrações e espectros de resposta, tópicos teóricos que fundamentam esse procedimento. Devido à escassez de informações divulgadas por se tratar de conteúdo militar, foi realizado um estudo de caso para uma estrutura simples, uma viga engastada e seus resultados foram comparados com um prévio trabalho publicado. Com isso, foi possível a aplicação do DDAM em uma estrutura mais complexa como o vaso do reator nuclear do tipo PWR de um submarino, ainda que em um modelo simplificado desse equipamento. No entanto, os resultados mostraram a validade do uso do DDAM na análise estrutural dinâmica de equipamentos de uma maneira qualitativa. / The main purpose of this dissertation is to verify the use of the Dynamic Design Analysis Method DDAM in the study of structures subjected to shock loadings. This method was developed by the U.S. Navy and is intended to estimate inertial forces resultant from the response of shipboard equipment, from surface ships or submarines, due to impulsive loads or, more precisely, underwater pressure shock waves. To fully comprehend this method, it was necessary to acknowledge fundamentals of dynamics of structures like free vibrations, response spectrum analysis correlated topics. And due to lack of public information since it is a military technology, a case study of a cantilever beam was done with its results compared to a previous published paper. Then, the DDAM was applied to a more complex structure a PWR nuclear reactor vase simplified model, in order to show the effectiveness of the method in dynamic structural analysis.
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Seismická analýza čerpadla 200-QHD / Seismic Analysis of The Pump 200-QHDČapičík, Martin January 2014 (has links)
The main goal of this thesis is dynamic analysis of shaft of booster pump QHD-200. In the beginning we offer basic equations generally used in dynamics and common/possible methods for their solution. Then we focus on specific problems connected with rotor dynamics and using simple Laval rotor we show their mathematical interpretation. Based on given load as accelerogram we create response spectrum in different ways (using different methods) and compare their CPU time demand. In the next part we make three finite element models of different physical level. We perform modal analysis and comparison of eigen frequencies, mode shapes. In following chapter transient analysis was performed on all models. As load we use accelerogram. We evaluate translations in particular positions of model. After that, we decide whether or not gap between impeller and stator case will be erased. Finally we make assessment of force acting upon bearings.
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Análisis de la amplificación sísmica de edificios del Cercado de Lima – Lima y La Punta – Callao por medio del método modal espectral y tiempo – historia mediante acelerogramas sintéticos / Analysis of the seismic amplification of the buildings in Cercado de Lima - Lima and La Punta - Callao by modal response spectrum analysis and time-history analysis by synthetic accelerogramsCastillo Cano, Ronald Daniel, Young del Aguila, Fredy Renan 30 November 2019 (has links)
Actualmente la población limeña no cuenta con viviendas propias y seguras; por ello, surge el auge del rubro de la construcción masiva con grandes edificaciones multifamiliares, cuya resistencia al impacto telúrico de enorme magnitud de 8 a 9 grados sigue en prueba sísmica; por ende, es muy relevante realizar la comparación del análisis del método modal espectral de la estructura (desplazamientos y aceleraciones respecto al suelo) y un análisis del método tiempo-historia donde se obtendrán las deformaciones máximas de la estructura de los edificios en este presente estudio; asimismo, evaluará la vulnerabilidad de la construcción estructural mediante acelerogramas sintéticos utilizando como espectro objetivo el espectro de peligro uniforme obtenido en el Parque de la Reserva, Cercado de Lima, por medio de un estudio peligro sísmico para un periodo de retorno de 475 años, reconociendo el comportamiento estructural ante un sismo de gran magnitud.
El presente estudio titulado: Análisis de la amplificación sísmica de edificios del Cercado de Lima – Lima y La Punta – Callao por medio del análisis modal espectral y tiempo – historia mediante acelerogramas sintéticos; cuyo objetivo es realizar la comparación de dichos métodos en 4 edificios (2 de 5 niveles y 2 de 12 niveles) cuya configuración estructural es de muros de concreto armado, los cuales se estudiaran en dos distintos tipos de suelo (Cercado de Lima y La Punta) con la finalidad de obtener resultados de derivas, fuerzas, desplazamientos y aceleraciones para determinar la amplificación sísmica en los suelos mencionados, y así optar por el método de análisis más óptimo.
Asimismo, el propósito del presente estudio es conocer el comportamiento de la edificación acorde con la realidad peruana; es decir edificaciones con periodos cortos; el cual evaluará la vulnerabilidad mediante acelerogramas sintéticos, reconociendo el comportamiento estructural ante una eventualidad sísmica de gran magnitud. / Currently, the population of Lima does not have their own and secure homes; For this reason, the boom in the field of massive construction emerges with large multi-family buildings, whose resistance to the telluric impact of enormous magnitude of 8 to 9 degrees continues in seismic testing; therefore, it is very relevant to make the comparison of the analysis of the spectral modal method of the structure (displacements and accelerations with respect to the ground) and an analysis of the time-history method where the maximum deformations of the structure of the buildings will be obtained in this present study. ; Likewise, it will assess the vulnerability of structural construction using synthetic accelerograms using the uniform hazard spectrum obtained in Parque de la Reserva, Cercado de Lima as the objective spectrum, through a seismic hazard study for a return period of 475 years, recognizing structural behavior in the face of a large earthquake.
The present study entitled: Analysis of the seismic amplification of buildings in Cercado de Lima - Lima and La Punta - Callao by means of spectral modal analysis and time - history using synthetic accelerograms; the objective of which is to compare these methods in 4 buildings (2 of 5 levels and 2 of 12 levels) whose structural configuration is made of reinforced concrete walls, which will be studied in two different types of soil (Cercado de Lima and La Punta ) in order to obtain results of drifts, forces, displacements and accelerations to determine the seismic amplification in the mentioned soils, and thus opt for the most optimal analysis method.
Likewise, the purpose of this study is to know the behavior of the building in accordance with the Peruvian reality; that is to say buildings with short periods; which will assess vulnerability using synthetic accelerograms, recognizing the structural behavior in the event of a large seismic event. / Tesis
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