L’objectif de cette thèse est d’explorer de nouvelles technologies permettant de faciliter l’intégration des isolateurs dans les chaînes radiofréquences de satellites. Ces composants sont utilisés pour contrôler l’adaptation des amplificateurs dans les sections d’entrée et de sortie des équipements RF bas niveaux. Nous proposons deux voies de réalisation de ces isolateurs. Une première voie basée sur l’utilisation de matériaux ferricomposites est étudiée pour concevoir des composants en bande Ku. Une deuxième voie, basée sur l’utilisation d’hexaferrites de strontium et de baryum préorientés, a été étudiée pour concevoir des composants auto-polarisés (sans aimants) en bandes Q et Ka. / The goal of this PhD thesis is to explore new technologies that make possible to improve the integration of isolators in radiofrequency chain of satellites. These components are especially used to control matching of amplifiers.We propose two ways of producing these isolators. At first, ferricomposite materials are studied to design low-cost isolators at Kuband.Then, we studied pre-oriented strontium or barium hexaferrites to design self-biased components (without magnets) for Q and Ka band frequencies.

Ante la constante amenaza sísmica que posee la costa peruana, se pretende resolver el problema de seguridad en los puentes, garantizando su funcionalidad ante potenciales desplazamientos superiores a los normados por los códigos peruanos de diseño sísmico. Se propone como solución la utilización de los aisladores sísmicos conocidos como Péndulos de Triple Fricción para lograr controlar los desplazamientos que generan sismos máximos donde los aisladores elastoméricos no pueden hacerlo. Se establece un criterio de utilización de los espectros de respuesta sísmica para las pseudo-aceleraciones, que coincide con los eventos sísmicos pronosticados por las estadísticas del Instituto Geofísico del Perú. Se modelan ocho casos de puentes típicos de la zona de estudio, de acuerdo a los datos proporcionados por el Ministerio de Transportes y Comunicaciones. También, se elaboran plantillas de diseño para apoyos elastoméricos y péndulos de triple fricción según los códigos regentes y los principales fabricantes de estos tipos de aisladores. Finalmente, esta investigación busca proponer la tendencia a la necesidad de implementación de péndulos de triple fricción con el fin de garantizar la funcionalidad continua de los puentes aun en situaciones de eventos sísmicos extremos. / In view of the constant seismic threat posed by the Peruvian coast, it is intended to solve the safety problem in the bridges, guaranteeing their functionality in the event of potential displacements greater than those regulated by the Peruvian seismic design codes. As a solution, the use of seismic isolators known as Triple Friction Pendulums is proposed to control the displacements that generate maximum earthquakes where elastomeric isolators cannot. A criterion for the use of seismic response spectra for pseudo-accelerations is established, which coincides with the seismic events predicted by the statistics of the Geophysical Institute of Peru. Eight cases of typical bridges in the study area are modeled, according to the data provided by the Ministry of Transport and Communications. Also, design templates for elastomeric bearings and triple friction pendulums are developed according to the governing codes and the main manufacturers of these types of insulators. Finally, this research seeks to propose the trend towards the need for the implementation of triple friction pendulums in order to guarantee the continuous functionality of the bridges even in situations of extreme seismic events. / Tesis

No description available.

En muchos países sufren bastantes movimientos sísmicos, que en algunos casos de severa intensidad, que han ocasionado pérdidas de vidas humanas, económicas. Por ello, se realiza el diseño de edificaciones para soportar sismo de gran intensidad y que el comportamiento de la estructura sea inelástico, para que no pueda colapsar y permita la evacuación de las personas. Ante esta situación, la estructura queda severamente dañada y el costo de reparación es alto. En las últimas décadas, se ha generado sistemas de protecciones sísmicas, lo que engloba un amplio estudio de variedades y tipos de investigaciones. Uno de los temas más estudiados son los sistemas de aisladores sísmicos, ya que separa la superestructura del suelo, es decir que los desplazamientos y aceleraciones de la estructura y del suelo son diferentes. En este estudio se propone el uso del sistema de aisladores sísmicos, con el uso del aislador elastomérico con núcleo de plomo (Lead Rubber Bearing, siglas en ingles LRB), se hace el diseño del aislador de un edificio de concreto armado de diferentes alturas (6, 8 y 10 pisos) con 4 normas de diferentes países (NTP E.031, NCh 2745, ASCE 7-16 y NZS 1170.5). Para poder identificar los factores de mayor importancia en un diseño de aislador. Finalmente, se realiza la comparación de las derivas, desplazamientos y aceleraciones. / In many countries they suffer quite a few seismic movements, which in some cases of severe intensity, that have caused loss of human lives, economic losses. For this reason, buildings are designed to withstand high-intensity earthquakes and the behavior of the structure is inelastic, so that it cannot collapse and allows the evacuation of people. In this situation, the structure is severely damaged and the cost of repair is high. In the last decades, systems of seismic protection have been generated, which includes a wide study of varieties and types of investigations. One of the most studied subjects is the systems of seismic isolators, since it separates the superstructure from the soil, that is to say, the displacements and accelerations of the structure and the soil are different. In this study, the use of the seismic isolator system is proposed, with the use of the elastomeric lead rubber bearing (LRB), the isolator design of a reinforced concrete building of different heights (6, 8 and 10 floors) with 4 standards from different countries (NTP E.031, NCh 2745, ASCE 7-16 and NZS 1170.5). In order to identify the most important factors in an insulator design. Finally, the comparison of drifts, displacements and accelerations is made. / Tesis

The launch environment experiences many vibration, shock, and acoustic loads. A great concern is the high random vibration levels that can damage components and spacecraft structures, which can cause a mission failure. An effective method of reducing high frequency energy is using isolators. Overall, the need for vibration isolation has been increasing because there has been an increase in the use of mechanisms in which vibrations are prevalent. In addition, there has not been extensive research on the effects of isolators that are outgassed and cured. Therefore, it is important to investigate and understand the vibrational effects on isolators. It is convenient to outgas and cure isolators for the benefit of some components because that eliminates contamination, but outgassing and bake-out could potentially affect the frequency response of the isolator system in a negative way. It is valuable to investigate how much outgassing and bake-out might affect the performance, if any, of the vibration isolator in order to benefit companies who may need that kind of information. The vibration isolators used for the purpose of this research were twenty E22-02-40 isolators provided by Barry Controls, a Hutchinson Group Company. The E22-02-40 isolators were outgassed and cured (heated at high temperatures) in order to be turned from grade C into grade A level for outgassing. Then the vibrational performance of those isolators were tested and compared to the isolators that were not outgassed and not cured. Vibration tests were run in the flat frequency spectrum and high frequency spectrum. The maximum percent difference occurred in the grade A level isolators, in which the first frequency mode increased by 33.3 % in the z direction from the grade C isolators. A numerical finite element analysis was performed on Abaqus/CAE in order to verify the experimental results. In addition, a swelling test was conducted on the isolators to test their physical characteristics change after they were outgassed and cured.

<p>Real-time hybrid simulation (RTHS) has demonstrated certain advantages over conventional large-scale testing. In an RTHS, the system that is under study is partitioned into a numerical and a physical substructure, where the numerical part is comprised of those elements that are easier to model mathematically, while the physical part consists of those that present a complex behavior difficult to capture in a numerical model. The most complex part of this study is the isolation system, a technology used to protect structures against earthquakes by modifying how they respond to ground motions. Unbonded Fiber Reinforced Elastomeric Isolators (UFREIs) are devices that can accomplish this task and have gained attention in recent years because of their modest but valuable features that make them suitable for implementation in low-rise buildings and in developing countries because of their low cost. Our end goal for this work is to enable the testing of scaled versions of these elastomeric isolators to understand their behavior under shear tests and realistic loading. </p> <p>A testing instrument was designed and constructed to apply a uniaxial compressive force up to 22kN and a shear force of 8kN simultaneously to the specimens. A testing program was conducted where four primary sources of signal distortion were identified as caused by the servo-hydraulic system. From these results, a mechanics-based model was developed to understand better the dynamics that the sliding table can introduce to the measured signals accounting for inertial and dissipative forces. Two Bouc-Wen models were implemented to simulate the behavior of the UFREIs. The first only accounts for the hysteretic behavior of the isolator, and the second accounts for the additional nonlinearities found in the isolator’s behavior. These models were assembled in a virtual RTHS which is available to users interested in learning the applications of RTHS of a base-isolated structure with a nonlinear component.</p> <p>An RTHS experiment was conducted in the IISL where the control system comprised a delay compensator and a proportional-integral controller, which exhibited a good tracking performance with minimal delay and low RMSE. However, it can increase the distortion of the oil-column resonance in the measured signals. The simulation captures the behavior of the isolated structure for small displacements. However, it underestimates the displacement of the full-scale specimen for large displacements. The RTHS showed a better approximation of the displacement of the full-scale structure than the theoretical behavior approximated by the Bouc-Wen models.</p>

Les isolateurs optiques sont des composants non-réciproques très important dans les systèmes de télécommunication optique. Actuellement les composants commercialisés sont tous discrets, à cause de la difficulté d’intégration des matériaux magnéto-optiques avec les technologies de l’optique intégrée. L’objectif de ma thèse était d’ouvrir une nouvelle voie technologique pour aboutir à une telle intégration. Pour cela nous avons développé une approche basée sur l’utilisation d’un matériau magnéto-optique composite complètement compatible avec la technologie d’échange d’ions sur verre. Ce matériau est élaboré par la voie sol-gel organique-inorganique et dopé par des nanoparticules magnétiques de ferrite de Cobalt (CoFe204). Il a montré des potentialités très prometteuses, illustré par une rotation Faraday spécifique de 420°/cm (@1550nm). Ce composite est déposé par la méthode dip-coating sur un guide fait par échange ionique d’Ar+/Na+, avec des extrémités enterrées par la méthode d’enterrage sélective pour faciliter le couplage-découplage de la lumière dans la structure hybride. Enfin, un traitement thermique (<100°C) et un traitement UV compatibles avec le procédé d’échange d’ions sur verre sont appliqués sur le dispositif pour finaliser la couche magnéto-optique. La caractérisation optique de notre dispositif a montré une bonne distribution de la lumière entre la couche magnéto-optique et le guide fait par échange d’ions (un bon confinement latéral). De plus, l’application d’un champ magnétique longitudinal au composant a permis de démontrer une valeur de conversion de mode TE-TM qui correspond bien à la quantité de la lumière confinée dans la couche magnéto-optique et la biréfringence modale de la structure. Donc, le but principal de la thèse est atteint, et ces résultats montrent la faisabilité d’un convertisseur de mode TE-TM compatible avec la technologie d’optique intégrée sur verre / Optical isolators are essential nonreciprocal devices used in optical communication systems. Currently, these components are commercially available but only in bulk form, due to the difficulties to embed magneto-optical materials with integrated classical technologies. To overcome this problem, our group has developed a new approach based on composite magneto-optical matrix that is fully compatible with ion-exchanged glass waveguide technology. This material is developed by organic inorganic sol-gel process and doped by magnetic nanoparticles (CoFe2O4). Such a magneto-optical composite matrix has shown promising potentialities illustrated by a specific Faraday rotation of 420°/cm (@1550nm). Using dip-coating technique, a composite layer was coated on a glass substrate containing straight channel waveguide made by a silver/sodium ion exchange. The extremities of the guides were previously buried using selective buried method in order to facilitate coupling-decoupling of light in hybrid structure. Last, a soft annealing (<100°C) and UV treatment, both compatible with the ion-exchanged process, have been implemented to finalize the magneto-optical film. Optical characterization demonstrated a good distribution of light between the magneto-optical thin film and the ion-exchanged waveguide (good lateral confinement). Furthermore TE to TM mode conversion has been observed when a longitudinal magnetic field is applied to the device. The amount of this conversion is in good agreement with the distribution of light between the layer and the guide obtained by numerical calculations, and the modal birefringence of the structure. So, the aim of my thesis is achieved and the results demonstrate the feasibility of TE to TM mode converter fully compatible with glass integrated optics