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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Aplicación de métodos de inspección y reparación en viviendas de albañileria confinada con presencia de daños en sus elementos estructurales provocado por un sismo

Chavez Huerta, Brian Francisco, Espíritu Castillejo, Martín Andree 24 October 2019 (has links)
Los sismos a través del tiempo han sido perjudiciales en el desarrollo de construcciones hechas por el hombre. Un sismo es un movimiento repentino del terreno producido por fuerzas que actúan en el interior del planeta; sus orígenes son numerosos pero el más importante son los choques entre las placas tectónicas. Respecto a las estructuras dañadas por el sismo, en la mayoría de los casos, son las viviendas familiares las que se ven perjudicadas en mayor medida, son muchas las causas, pero uno de los más importantes es la construcción de edificaciones de albañilería confinada realizadas sin ningún parámetro ingenieril (Hermosa, 2003). Por ello, cuando ocurre un sismo suele aparecer fallas en sus elementos estructurales, que en algunos casos no se le toma la debida importancia por el usuario, vale mencionar que este acto no es el correcto debido a que, si ocurriera un sismo de alta magnitud podría colapsar y como consecuencia se perderían vidas humanas. Por esta razón, a todos los profesionales dedicados al rubro de la construcción les es imprescindible contar con nociones de inspección de los daños estructurales y asimismo saber repararlas. En este documento se aprenderá las diferentes aplicaciones de métodos de inspección de fisuras en elementos estructurales tanto en columnas, vigas y muros, pero enfocado principalmente en el muro ya que, en esta técnica constructiva, el muro es el que soporta los esfuerzos, este análisis será de dos formas: Evaluación rápida y evaluación detallada. En la evaluación rápida, se determina rápidamente el riesgo o seguridad que representa la estructura; esta información será almacenada en una aplicación, el cual será la herramienta para la evaluación con el fin de determinar el nivel de seguridad de la vivienda, las cuales son seguridad total, habitable, cuidado e insegura, estableciendo de esta manera si la vivienda es habitable o no (Pinto y Torres, 2016). Finalmente, si la vivienda se encontrase en el nivel de seguridad de cuidado o insegura se pasará a una evaluación detallada; en esta evaluación se recomienda una inspección no mayor a 6 horas. En la evaluación detallada, se realiza una reevaluación de acuerdo a los niveles establecidos en la evaluación rápida, centrándose en los últimos niveles, cuidado e inseguro, respectivamente; se determinará las causas que originaron los daños, así como la magnitud de daños en los elementos estructurales a través de equipos de inspección, siendo algunos de ellos, el pacómetro y el comparador; para la posterior aplicación de diversos métodos de reparación. Finalmente, la reparación involucra la inyección de resina epoxi en grietas, reforzamiento con fibra de carbono, malla electrosoldada, entre otros. El éxito de la aplicación de estos métodos tiene como objetivo lograr disminuir el porcentaje de probabilidad de colapso y eliminar la pérdida de vidas humanas que se realizará mediante un modelamiento de la vivienda reparada la cual tendrá que cumplir con las normas de diseño sismorresistente. Como resultado de este modelamiento en Etabs se pudo comprobar que efectivamente tras la reparación a través de fibra de carbono y malla electrosoldada en los muros de albañilería confinada, la estructura es capaz de soportar sismos de igual o mayor magnitud. / Earthquakes over time have been detrimental in the development of man-made constructions. An earthquake is a sudden movement of the land produced by forces acting inside the planet; Its origins are numerous but the most important are the clashes between the tectonic plates. Regarding the structures damaged by the earthquake, in most cases, it is family homes that are harmed to a greater extent, there are many causes, but one of the most important is the construction of confined masonry buildings made without no engineering parameter (Hermosa, 2003). Therefore, when an earthquake occurs, failures usually appear in its structural elements, which in some cases do not take due importance by the user, it is worth mentioning that this act is not correct because, if a high magnitude earthquake occurs It could collapse and as a result human lives would be lost. For this reason, all professionals dedicated to the construction sector are essential to have notions of inspection of structural damage and also know how to repair them. In this document we will learn the different applications of methods of inspection of fissures in structural elements both in columns, beams and walls, but focused mainly on the wall since, in this construction technique, the wall is the one that supports the efforts, this analysis It will be in two ways: Rapid evaluation and detailed evaluation. In the rapid assessment, the risk or safety of the structure is quickly determined; This information will be stored in an application, which will be the tool for the evaluation in order to determine the level of security of the house, which are total, habitable, careful and insecure security, establishing in this way if the house is habitable or not (Pinto y Torres, 2016). Finally, if the house is at the level of care or insecurity, a detailed evaluation will be carried out; In this evaluation, an inspection of no more than 6 hours is recommended. In the detailed evaluation, a reassessment is carried out according to the levels established in the rapid evaluation, focusing on the last levels, careful and insecure, respectively; the causes that caused the damage will be determined, as well as the magnitude of damage to the structural elements through inspection equipment, some of them being the pacometer and the comparator; for the subsequent application of various repair methods. Finally, the repair involves the injection of epoxy resin in cracks, reinforcement with carbon fiber, welded mesh, among others. The success of the application of these methods aims to reduce the likelihood of collapse and eliminate the loss of human lives that will be done through a modeling of repaired housing which will have to comply with seismic-resistant design standards. As a result of this modeling in Etabs, it was found that after the repair through carbon fiber and welded mesh in the confined masonry walls, the structure is capable of withstanding earthquakes of equal or greater magnitude. / Tesis
22

Robustness Evaluation of Long Span Truss Bridge Using Damage Influence Lines / 損傷影響線を用いた長大トラス橋のロバスト性評価

Mya, San Wai 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22417号 / 工博第4678号 / 新制||工||1730(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 高橋 良和, 教授 清野 純史, 教授 八木 知己 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
23

Nonlinear Seismic Responses of High-Speed Railway System considering Train-Bridge Interaction / 列車-橋梁連成系を考慮した高速鉄道システムの地震時非線形応答解析

Lu, Xuzhao 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22418号 / 工博第4679号 / 新制||工||1730(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 KIM Chul-Woo, 教授 清野 純史, 教授 杉浦 邦征 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
24

Reforzamiento estructural para mejorar el nivel de desempeño del Hospital Santa Rosa, implementando el diseño apropiado de amortiguadores fluido viscoso

Cáceres Pérez, Gladys, Pichihua Alata, Natali Sheyla 10 June 2020 (has links)
Movimientos telúricos ocurridos en distintas partes del mundo han originado considerables pérdidas económicas y humanas. Es importante mencionar también que, durante estos últimos años, en los principales países desarrollados tales como Taiwán, Japón y Estados Unidos se ha venido implementando nuevas tecnologías para mejorar el desempeño en las estructuras frente a acciones sísmicas como son los sistemas de protección sísmica. Uno de estos avances son los disipadores de energía fluido viscoso cuya implementación muestra resultados óptimos para el incremento del amortiguamiento y reducción de desplazamientos laterales. Para cumplir con el objetivo principal de la investigación, se evaluó el diseño estructural del bloque A2 del Hospital Santa Rosa, una edificación esencial ubicada en el distrito de Pueblo Libre, Lima. Se realizó el modelo y análisis sísmico de la estructura existente, cuyos resultados muestras derivas ( ∆=5.98%o ) mayores al límite establecido en la Norma E.030 ( ∆=5%o ). Además, presenta efectos de columna corta que originan el agrietamiento de las unidades de albañilería, hecho que los hace vulnerables. Frente a los resultados presentados se realiza una nueva modelación y análisis sísmico del bloque en estudio, considerando como reforzamiento los disipadores de fluido viscoso. Para ello, se analiza nuevamente la estructura a través de un análisis tiempo historia tomando distintas consideraciones como el sismo de diseño y las propiedades de los disipadores fluido viscoso en donde las derivas máximas se han reducido de 5.98%o a 3.30 %o. Adicionalmente, se analiza la estructura con una técnica de reforzamiento tradicional como son las placas de concreto armado, con el objetivo de evaluar la viabilidad de la primera propuesta. Los resultados indican que, con un reforzamiento de muros de concreto se obtiene una deriva de ∆=3.36%o y ∆=3.30%o empleando los disipadores viscosos, lo cual demuestra la viabilidad de la propuesta en respuestas estructurales. / Telluric movements in different parts of the world have caused considerable economic and human losses. It is also important to mention that, in recent years, in the main developed countries such as Taiwan, Japan and the United States, new technologies have been implemented to improve the performance of structures against seismic actions such as seismic protection systems. One of these advances are the viscous fluid energy dissipators whose implementation shows optimal results for increasing damping and reducing displacement. In order to comply with the main objective of the research, the structural design of block A2 of the Santa Rosa Hospital, an essential building located in the Pueblo Libre district, Lima, was evaluated. The seismic analysis and model of the existing structure was carried out, whose results show drifts ( ∆=5.98%o ) greater than the limit established in Standard E.030 ( ∆=5%o ). In addition, it presents short column effects that cause cracking of the masonry units, a fact that makes them vulnerable. In front of the presented results, a new modeling and seismic analysis of the block under study is performed, considering viscous fluid dissipators as reinforcement. For this, the structure is analyzed again through a time-history analysis taking different considerations such as the design earthquake and the properties of the viscous fluid heatsinks where the maximum drifts have been reduced from 5.98%o to 3 .30%o Additionally, the structure is analyzed with a traditional reinforcement technique such as reinforced concrete plates, with the aim of evaluating the feasibility of the first proposal. The results indicate that, with a reinforcement of concrete walls, a drift of ∆=3.36%o and ∆=3.30 is obtained using viscous heatsinks, which demonstrates the viability of the proposal in structural responses. / Tesis
25

SEISMIC PERFORMANCE OF HIGHWAY BRIDGES SUBJECTED TO STRONG EARTHQUAKES CONSIDERING VEHICLE-BRIDGE INTERACTION / 車両一橋梁の相互作用を考慮した強地震動を受ける橋梁の耐震性能に関する研究

Su, Danna 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21081号 / 工博第4445号 / 新制||工||1691(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 杉浦 邦征, 教授 KIM Chul-Woo, 教授 清野 純史 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
26

Time-domain Response of Linear Hysteretic Systems to Deterministic and Random Excitations.

Muscolino, G., Palmeri, Alessandro, Ricciardelli, F. January 2005 (has links)
No / The causal and physically realizable Biot hysteretic model proves to be the simplest linear model able to describe the nearly rate-independent behaviour of engineering materials. In this paper, the performance of the Biot hysteretic model is analysed and compared with those of the ideal and causal hysteretic models. The Laguerre polynomial approximation (LPA) method, recently proposed for the time-domain analysis of linear viscoelastic systems, is then summarized and applied to the prediction of the dynamic response of linear hysteretic systems to deterministic and random excitations. The parameters of the LPA model generally need to be computed through numerical integrals; however, when this model is used to approximate the Biot hysteretic model, closed-form expressions can be found. Effective step-by-step procedures are also provided in the paper, which prove to be accurate also for high levels of damping. Finally, the method is applied to the dynamic analysis of a highway embankment excited by deterministic and random ground motions. The results show that in some cases the inaccuracy associated with the use of an equivalent viscous damping model is too large.
27

SEISMIC DESIGN AND EVALUATION OF BASE ISOLATED STEEL STORAGE RACKS

Sabzehzar, Saman January 2016 (has links)
No description available.
28

Acelerogramas artificiais de sismos aplicados a edificações. / Artificial accelerograms of earthquakes applied to buildings.

Brito, Ronnie Chtcot 21 November 2017 (has links)
Apesar de fortes eventos sísmicos serem raros no Brasil, engenheiros estruturais brasileiros são frequentemente envolvidos em tal análise para os países latino-americanos vizinhos. Informações sobre históricos de aceleração sísmica, de natureza aleatória, não estão em geral disponíveis, devido, em parte, à falta de registros. Para contornar tal situação, os códigos de construção indicam o uso de acelerogramas artificiais, mas não fornecem metodologia para sua obtenção. A informação normalizada é o chamado espectro de resposta elástico, que fornece a aceleração de resposta máxima para um sistema linear de um grau de liberdade. Muitas pesquisas estão sendo desenvolvidas a fim de gerar acelerogramas artificiais compatíveis com os espectros de norma. Assim, neste trabalho se apresenta uma proposta para a geração de acelerograma artificial compatível com espectro de resposta regulamentar. Para exemplo de aplicação, é gerado um acelerograma artificial compatível com a Norma Brasileira NBR 15421: 2006 e aplicado à base de um edifício shear building de dez pavimentos e através de integração numérica por diferenças finitas passo-a-passo no domínio do tempo é calculado o deslocamento do último pavimento deste edifício. De forma semelhante, é gerado um acelerograma artificial compatível com a Norma Venezuelana COVENIN 1756: 2001 e aplicado à base de um reservatório d\'água sobre quatro pilares e estudado o seu comportamento elastoplástico perfeito. / Although strong seismic events are rare in Brazil, Brazilian structural engineers are often involved in such an analysis for neighboring Latin American countries. Information on seismic acceleration histories of a random nature is not generally available, due in part to the lack of records. To circumvent such a situation, building codes indicate the use of artificial accelerograms, but do not provide a methodology for obtaining them. The normalized information is the so-called elastic response spectrum, which provides the maximum response acceleration for a linear system of a degree of freedom. Many researches are being developed in order to generate artificial accelerograms compatible with the norm spectra. Thus, this paper presents a proposal for the generation of an artificial accelerogram compatible with a regulatory response spectrum. For an application example, an artificial accelerogram compatible with the Brazilian Standard NBR 15421: 2006 is generated and applied to the base of a ten-story shear building and through numerical integration by finite differences step-by-step in the time domain is calculated the displacement of the last floor of this building. Similarly, an artificial accelerogram is generated that is compatible with the Venezuelan Standard COVENIN 1756: 2001 and applied on the basis of a water reservoir on four pillars and studied its perfect elastoplastic behavior.
29

Seismic Analysis of Steel Wind Turbine Towers in the Canadian Environment

Nuta, Elena 06 April 2010 (has links)
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.
30

Seismic Analysis of Steel Wind Turbine Towers in the Canadian Environment

Nuta, Elena 06 April 2010 (has links)
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.

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