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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.
11

Propuesta de utilización de barras de Polímeros Reforzados con Fibras de Vidrio (PRFV), mediante la técnica Inhibir-Reparar-Fortalecer (IRF) para rehabilitación estructural en vigas y losas de concreto armado con refuerzo corroído / Proposal of Glass Fiber Reinforced Polymers (GFRP) bars using the technique Inhibiting-Repairing-Strengthening (IRS) for a structural rehabilitation in reinforced concrete beams and slabs with corroded reinforcement

Alarcon Ramirez, Stephany Guadalupe, Delgado Pereyra, Luis Enrique 15 May 2021 (has links)
La presente investigación se basa en el estudio de las barras de polímero reforzado con fibra de vidrio (PRFV) como propuesta de rehabilitación frente a agentes corrosivos en vigas y losas de concreto armado. Para esto se seleccionó un caso de estudio real, vivienda de tres niveles, ubicada en el distrito de Chorrillos, el cual presentaba una corrosión de 50% en el área nominal del acero de refuerzo. Asimismo, se utilizó como técnica de rehabilitación la denominada Inhibir-Reparar-Fortalecer (IRF) que se basa en la reestructuración de los componentes del elemento estructural; en otras palabras, es un proceso de restauración que parte de la eliminación total tanto del acero positivo corroído como del concreto afectado hasta la restauración del elemento estructural. Para realizar lo anteriormente mencionado, se distribuyó el trabajo en los siguientes puntos: un modelamiento de la estructura en ETABS, obtención de momentos últimos, diseño de la cantidad de barras de PRFV y explicación del procedimiento de rehabilitación total para ambos elementos estructurales. / The following investigation is based on the study of Glass Fiber Reinforced Polymer (GFRP) bars as a proposal for rehabilitation against corrosive agents in reinforced concrete beams and slabs. To accomplished this, a real case study was selected, a three-level housing, located in the district of Chorrillos, which had a 50% corrosion in the nominal area of ​​the reinforcing steel. Likewise, a technique called Inhibiting-Repairing-Strengthening (IRS) was used, this technique is based on the restructuring of the components of the structural element; in other words, it is a restoration process that starts from the total elimination of the corroded positive steel and the affected concrete. To carry out the aforementioned, the work was distributed in the following points: a structure modeling in ETABS, factored moment at section, design of the number of GFRP bars and a total rehabilitation procedure for both structural elements. / Tesis
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12

Diseño por desempeño del reforzamiento sísmico de la Biblioteca Agrícola Nacional mediante el uso de métodos no convencionales

Chavez Morán, Brayan Yovanni, Matias Yataco, Carlos Manuel 07 July 2021 (has links)
En esta investigación se plantea el reforzamiento estructural de una edificación de concreto armado con más de 50 años de antigüedad. La estructura está conformada por pórticos y muros, teniendo un área de construcción de 1980 m2 y 4 niveles con altura total de 15.50 m. Además, se evalúa tres tipos de reforzamiento para la estructura antigua dando como propuesta final para el reforzamiento una de las alternativas presentadas. La primera alternativa de reforzamiento consiste en el uso de planchas de Steel Jacket con pernos de anclajes post instalados de Polímero Reforzado con Fibra de Carbono (CFRP) en columnas, la segunda alternativa consiste en el uso de planchas de CFRP con anclajes de CFRP en columnas mientras que la tercera alternativa consiste en el uso de planchas de CFRP en diagonal con anclajes de CFRP en sus extremos para asegurar que estas láminas resistan hasta sus alto niveles de tensión. Estos anclajes junto con las láminas en diagonal aportan a dar ductilidad al muro y a su vez resistan los efectos de deslizamiento en la base, falla que es muy común en estructuras rígidas como los muros. Cada metodología no convencional de reforzamiento usada en esta investigación se valida a través de resultados de ensayos de laboratorio de columnas y muros reforzados mediante las técnicas de cada una de las tres alternativas mencionadas. Se realizaron análisis estático no lineal – Pushover de cada alternativa de reforzamiento y se comparó con demanda del sismo de 1974 en Lima, escalando 3 registros sísmicos a un PGA de 0.45g que es la aceleración de diseño en Lima. Se demuestra que estas propuestas son efectivas para proporcionar incremento de capacidad de corte y desplazamiento en el diseño inelástico. Para el reforzamiento en columnas de 0.40mx0.80m los resultados muestras que ambos reforzamientos aumentan la ductilidad en más del 10%; por otro lado, la propuesta de reforzamiento en los muros de 40.00cm de espesor, produjo incluso mejores resultados aumentando la ductilidad en 100% y corte en la base en 100%. / In this research, the seismic retrofit of a reinforced concrete building with more than 50 years old is proposed. The structure is made up of frames and walls, having a construction area with 1980 m2 and 4 stories with a total height of 15.50 m. In addition, three kind of reinforcement are evaluated for the old structure, giving as a final proposal for reinforcement one of the alternatives presented. The first reinforcement alternative consists of the use of Steel Jacket with post-installed bolt anchors of Carbon Fiber Reinforced Polymers (CFRP) in columns, the second alternative consists of the use of CFRP jacket with CFRP anchors in columns. while the third alternative consists of the use of CFRP sheets diagonally with CFRP anchors at their ends to ensure that these sheets resist up to their high stress levels. These anchors together with the diagonal sheets contribute to give the wall ductility and in turn resist the effects of sliding at the base, a failure that is very common in rigid structures such as walls. Each non-conventional reinforcement methodology used in this research is validated through the results of laboratory tests of reinforced columns and walls using the techniques of each of the three alternatives mentioned. Non-linear static analysis - Pushover of each reinforcement alternative was performed and it was compared with the demand of the 1974 earthquake in Lima. There have been 3 seismic records and a PGA of 0.45g which is the design acceleration in Lima. It is shown that these proposals are effective for the levels of shear capacity and displacement in the inelastic design. For the columns of 0.40mx0.80m the results show that both reinforcements increase the ductility by more than 10%; On the other hand, the proposal of reinforcement in the walls of 40 cm of thickness, has obtained a better result in 100% and in the base in 100%. / Tesis
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13

Museo Aeronáutico del Perú / Aeronautical Museum of Peru

Maldonado Aste, Maria Elena 25 October 2021 (has links)
Lima posee museos de diversas tipologías. Unos adaptados en casas de personajes renombrados, viejas mansiones, o espacios que poseen alguna cualidad constructiva, pertenecientes a épocas anteriores pero cercanas de nuestra historia. Otros museos, en edificios imponentes, de gran tamaño hacia el exterior, pero con salas reducidas hacia interior los que generan límites definidos a la exhibición, sin haber nacido para realmente ser áreas de exhibición. El Museo Aeronáutico del Perú, fue originalmente ubicado en los dormitorios de la antigua Escuela de  Oficinales en la “Base Aérea las Palmas” y posteriormente situado en el Castillo Rospigliosi, antigua sede de logística de la FAP, en ambos casos con adaptaciones en espacios reducidos y exhibiciones limitadas. Asimismo, los aviones se encontraban ubicados en las afueras de edificios de las Fuerzas Armadas, en la calle sobre avenidas, en el Aeropuerto y en zonas del Callao, sin dar apropiadamente conocer su historia y características. El presente proyecto está concebido como un espacio especializado: Tanto cultural y de identidad referente la aviación, a hechos heroicos de personas que dieron su vida con un fin particular, de la complejidad de las maquinas que son capaces de  trasladarnos a lugares remotos y volar. Dar a conocer en verdadera magnitud las imponentes naves en un espacio adecuado de gran envergadura y luces adecuada que exhiban además la imponencia de su diseño y estructura. Generar un espacio de recreación temático, con exhibiciones estáticas al interior y dinámicas al exterior. / Lima, owns museums of various typologies. Some of them adapted in houses of renowned persons, older mansions, or at spaces that represents some constructive qualities from closer past times. Other museums, at gorgeous structures oversized outside going out, but with not so bigger inner areas, that created hard boundaries to exhibitions and limited proportions. Aeronautical Museum of Peru, was originally located at the bedrooms older area of the Peruvian Military Officers School at the well known base of Las Palmas, and later relocated at the spaniel Castillo Ropigliosi, ancient Logistic Offices of the FAP, but both of them with many restrictions to the spaces and areas to be used. Even more, air units have always been located at the street over avenues, outside of Military buildings, at the International Airport, or in El Callao zones, without let us know their true stories and characteristics. Those project has been designed as an specialized zone: Cultural and also with a proper identity, deeply referred to Peruvian aviation, including heroic actions of people that gave their own life, also referring to machines complexity, all of them that were capable to move us or to transport us, according they were used. Its also been designed in order to show us real sizes and adequate references to their flying qualities. Also to generate a thematic and recreational area, allowing us to visit statics inner exhibits, but also outer and dynamic presentations, in order to feel the power of machines. / Tesis
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14

Contribuições ao dimensionamento de torres eólicas de concreto. / Contributions to design of concrete wind towers.

Gama, Paulo Vitor Calmon Nogueira da 20 May 2015 (has links)
O trabalho dedica-se ao estudo das torres eólicas protendidas de concreto, com a finalidade de promover a discussão sobre os critérios de dimensionamento, tema de grande relevância na atualidade. Para tal, foi considerada uma torre eólica de 100 m de altura provida de turbina de 5 MW, cujas ações foram obtidas da literatura. O carregamento de vento ao longo da torre foi tratado como estático equivalente de acordo com disposições normativas, através de uma forma simplificada para a adoção de uma velocidade de projeto equivalente à incidente no rotor. Com base na literatura, apenas as condições mais críticas foram adotadas no dimensionamento. As combinações entre os carregamentos e os coeficientes parciais de segurança foram delineados a partir do método dos estados limites, o qual se encontra amplamente difundido em normas de projeto. Os esforços e deslocamentos na torre foram obtidos pelo método dos elementos finitos com discretização em elementos finitos unidimensionais, considerando as não linearidades física e geométrica por intermédio do acoplamento de um programa comercial de elementos finitos com algoritmo desenvolvido em linguagem MATLAB, que tanto define as diversas geometrias de cada elemento ao longo da torre (seção variável), como obtém para cada um: a armadura ativa longitudinal a partir de perdas de protensão recalculadas, o diagrama momento-curvatura-força normal, e a armadura passiva longitudinal escalonada, que é otimizada durante o processo do dimensionamento. Quanto à resistência ao esforço cortante das seções anulares, foi proposto um modelo que apresentou boa concordância com os resultados experimentais obtidos na literatura. Além dos concretos convencionais, é discutido o estado-da-arte do concreto de ultra-alto desempenho reforçado com fibras, CUADRF, tratando sobre seu desenvolvimento histórico, composição, diferentes tipos, propriedades mecânicas, aplicações, recomendações para projeto e as simplificações adotadas quanto ao seu uso nas torres eólicas. Ao final foram realizadas análises paramétricas relativas à geometria e à classe de concreto para dois tipos de torres: em tronco de cone e de variação parabólica. Uma das principais conclusões do trabalho é que a otimização da área de aço passivo ocorre de forma sistemática para as torres de frequência natural mais baixa, tornando indispensável o uso de um modelo não linear para o correto dimensionamento. Além disso, as torres obtidas foram comparadas através do custo material total, constatando-se que as torres mais econômicas possuíam variação parabólica. Isso permitiu aferir um valor inicial para o qual o uso do CUADRF em torres eólicas passaria a ser competitivo. / The work is dedicated to the study of prestressed wind towers of concrete, in order to promote discussion on the design criteria, highly relevant topic today. For this purpose, it was considered a wind tower 100 m high provided with 5 MW turbine, whose actions were obtained from the literature. The wind loading along the tower was treated as static equivalent in accordance with design codes, through a simplified way for the adoption of a design speed equivalent to that incident on the rotor. Based on the literature, only the most critical conditions were adopted in the design. The combinations between loads and partial safety factors were outlined by the limit states method, which is widespread in design standards. The forces and displacements in the tower were obtained by the finite element method with discretization in frame elements, through material and geometric nonlinearities. This was done through coupling of a commercial finite element program with algorithm developed in MATLAB language, which defines both the various geometries of each element along the tower (variable section), and obtains for each: prestressing reinforcement from recalculated prestressing losses, the moment-curvature-normal diagram, and the stepped longitudinal passive reinforcement that is optimized during the design process. For the shear strength of the annular sections, a model that showed good agreement with the experimental results obtained in the literature was proposed. In addition to conventional concrete, the state-of-the art of ultra-high performance fiber reinforced concrete, UHPFRC, is discussed, dealing on its historical development, composition, different types, mechanical properties, applications, recommendations for design and simplifications adopted on its use in wind towers. At the end were performed parametric analyzes of the geometry and the concrete class for two types of towers: frustoconical and with parabolic variation. One of the main conclusions is that the optimization of passive steel area occurs systematically to the lower natural frequency towers, making it essential to use a nonlinear model for proper design. Moreover, the towers obtained were compared with the total material cost, having noticed that most economical towers had parabolic variation for the constraints here imposed. This allowed the assessment of an initial value for which the use of UHPFRC in wind turbine towers would be competitive.
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15

Contribuições ao dimensionamento de torres eólicas de concreto. / Contributions to design of concrete wind towers.

Paulo Vitor Calmon Nogueira da Gama 20 May 2015 (has links)
O trabalho dedica-se ao estudo das torres eólicas protendidas de concreto, com a finalidade de promover a discussão sobre os critérios de dimensionamento, tema de grande relevância na atualidade. Para tal, foi considerada uma torre eólica de 100 m de altura provida de turbina de 5 MW, cujas ações foram obtidas da literatura. O carregamento de vento ao longo da torre foi tratado como estático equivalente de acordo com disposições normativas, através de uma forma simplificada para a adoção de uma velocidade de projeto equivalente à incidente no rotor. Com base na literatura, apenas as condições mais críticas foram adotadas no dimensionamento. As combinações entre os carregamentos e os coeficientes parciais de segurança foram delineados a partir do método dos estados limites, o qual se encontra amplamente difundido em normas de projeto. Os esforços e deslocamentos na torre foram obtidos pelo método dos elementos finitos com discretização em elementos finitos unidimensionais, considerando as não linearidades física e geométrica por intermédio do acoplamento de um programa comercial de elementos finitos com algoritmo desenvolvido em linguagem MATLAB, que tanto define as diversas geometrias de cada elemento ao longo da torre (seção variável), como obtém para cada um: a armadura ativa longitudinal a partir de perdas de protensão recalculadas, o diagrama momento-curvatura-força normal, e a armadura passiva longitudinal escalonada, que é otimizada durante o processo do dimensionamento. Quanto à resistência ao esforço cortante das seções anulares, foi proposto um modelo que apresentou boa concordância com os resultados experimentais obtidos na literatura. Além dos concretos convencionais, é discutido o estado-da-arte do concreto de ultra-alto desempenho reforçado com fibras, CUADRF, tratando sobre seu desenvolvimento histórico, composição, diferentes tipos, propriedades mecânicas, aplicações, recomendações para projeto e as simplificações adotadas quanto ao seu uso nas torres eólicas. Ao final foram realizadas análises paramétricas relativas à geometria e à classe de concreto para dois tipos de torres: em tronco de cone e de variação parabólica. Uma das principais conclusões do trabalho é que a otimização da área de aço passivo ocorre de forma sistemática para as torres de frequência natural mais baixa, tornando indispensável o uso de um modelo não linear para o correto dimensionamento. Além disso, as torres obtidas foram comparadas através do custo material total, constatando-se que as torres mais econômicas possuíam variação parabólica. Isso permitiu aferir um valor inicial para o qual o uso do CUADRF em torres eólicas passaria a ser competitivo. / The work is dedicated to the study of prestressed wind towers of concrete, in order to promote discussion on the design criteria, highly relevant topic today. For this purpose, it was considered a wind tower 100 m high provided with 5 MW turbine, whose actions were obtained from the literature. The wind loading along the tower was treated as static equivalent in accordance with design codes, through a simplified way for the adoption of a design speed equivalent to that incident on the rotor. Based on the literature, only the most critical conditions were adopted in the design. The combinations between loads and partial safety factors were outlined by the limit states method, which is widespread in design standards. The forces and displacements in the tower were obtained by the finite element method with discretization in frame elements, through material and geometric nonlinearities. This was done through coupling of a commercial finite element program with algorithm developed in MATLAB language, which defines both the various geometries of each element along the tower (variable section), and obtains for each: prestressing reinforcement from recalculated prestressing losses, the moment-curvature-normal diagram, and the stepped longitudinal passive reinforcement that is optimized during the design process. For the shear strength of the annular sections, a model that showed good agreement with the experimental results obtained in the literature was proposed. In addition to conventional concrete, the state-of-the art of ultra-high performance fiber reinforced concrete, UHPFRC, is discussed, dealing on its historical development, composition, different types, mechanical properties, applications, recommendations for design and simplifications adopted on its use in wind towers. At the end were performed parametric analyzes of the geometry and the concrete class for two types of towers: frustoconical and with parabolic variation. One of the main conclusions is that the optimization of passive steel area occurs systematically to the lower natural frequency towers, making it essential to use a nonlinear model for proper design. Moreover, the towers obtained were compared with the total material cost, having noticed that most economical towers had parabolic variation for the constraints here imposed. This allowed the assessment of an initial value for which the use of UHPFRC in wind turbine towers would be competitive.
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16

Design parametrické ortézy horní končetiny / Design of the parametric orthosis for upper limb

Kosová, Barbora January 2017 (has links)
This thesis deals with the design and manufacturing of custom-made immobilization orthosis for the upper limb. Emphasis is put on the digitization of the approach and integration of additive manufacturing in the workflow of splint production. The solution proposes automatic model construction based on a 3D scan. Such a model is further parametrized in order to provide splinting practitioners with customization abilities. Particular attention is paid to the changes of limb volume due to swell, where the use of auxetic structures is suggested.
17

Železobetonový skelet / Concrete skeleton construction

Dvořák, Tomáš January 2012 (has links)
The master’s thesis is focused on a design of reinforced concrete prefabricated skeleton of the sports hall. Object of the design is internal traverse frame of the hall which consists of reinforced concrete prestressed truss, columns and concrete pile construction of foundation. Thesis includes working-out of static calculation, elaboration drawings of shape, reinforcement of solved elements and evolvement of assembly drawings. The rest of the project parts are not analyzed.
18

Železobetonová konstrukce obytného domu / Reinforced concrete structure of an apartment block

Čairović, Dorde January 2013 (has links)
The master thesis is aimed for design and assessment of main bearing segments of reinforced concrete structure of apartment block: monolithic reinforced concrete slab over the second floor, foundation slab, stairway slab, pillar and wall beam. Constituent part of the thesis is also drawing documentation of reinforcement of selected segments. Calculation of the internal forces is made at graphical software system Scia Engineer.
19

Úprava a změna průmyslové haly / Adaptation and modification of the industry hall

Benda, Lukáš January 2015 (has links)
The master’s thesis is focused on a design of reinforced concrete refabricated skeleton of the industrial hall. Object of the design are two internal traverse frames of the hall which consists of reinforced concrete truss, columns, girder and concrete flat foundation. Thesis includes working-out of static calculation, elaboration drawings of shape, reinforcement of solved elements and evolvement of assembly drawings. The rest of the project parts are not analyzed.
20

Nosná konstrukce nemocničního pavilonu / Load-bearing Structure of Hospital Pavilion

Hůrka, Jiří January 2015 (has links)
The thesis is focused on the design and assessment of selected elements of load-bearing structure of hospital pavilion. This pavilion consisted of board frame with additionally lined self-supporting perimeter cover. Selected elements of the structure are locally supported slab, columns, foundation pad and staircase . Computational model was assembled of the software RFEM5. Internal forces locally supported slab were verified by manual calculation. The design documentation consist of engineering report, structural analysis and shape and reinforcements drawings of selected structural elements.

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