Un acier austénitique stabilisé au titane, le 15-15Ti AIM1, a été choisi à l'état écroui comme matériau de référence des gaines de combustible du premier coeur d'ASTRID (prototype de Réacteur à Neutrons Rapides (RNR) refroidi au sodium). Cette étude contribue à la compréhension de l'évolution microstructurale sous irradiation de l'AIM1 à forte dose (>100 dpa) et en particulier des mécanismes de gonflement. Des campagnes d'irradiations aux ions de l'AIM1 et de son précurseur le 15-15Ti D4 (AIM1 sans phosphore), ont été menées sur l'installation Jannus-Saclay. Ces irradiations ont été réalisées jusqu'à une dose de 150 dpa en simple faisceau Fe2+ et 120 dpa en double faisceaux Fe2+ et He+ entre 550 et 630°C pour étudier les effets de l'hélium. En parallèle, des recuits thermiques à 650°C de durées comparables aux temps d'irradiation (<100h) ont été réalisés pour séparer les effets de la température et de l'irradiation. Les microstructures et les défauts d'irradiation ont été caractérisés principalement au microscope électronique à transmission (MET) et à la sonde atomique tomographique (SAT). Pendant les recuits thermiques à 650°C, une précipitation rapide de carbures de titane nanométriques sur les dislocations est observée. Une faible densité d'amas enrichis en phosphore (germes de phosphures) a également été détectée. Après irradiation aux ions, la microstructure de l'AIM1 et du 15-15Ti fait apparaître une population dense de boucles fautées de Frank reparties de manière homogène et qui évolue peu avec la dose (entre 45 et 150 dpa). La précipitation est constituée principalement de carbures de titane nanométriques, de phosphures (dans l'AIM1) et de carbures de chrome. La précipitation de phosphures dans l'AIM1 apparait accélérée par l'irradiation. Une ségrégation du Ni et du Si sur les dislocations est aussi mise en évidence. Les irradiations en simple faisceau même à 150 dpa créent une faible densité de cavités réparties de façon hétérogène dans les grains. Il a été montré que l'implantation simultanée d'hélium à 1 appm/dpa conduit à une densité de cavités nettement plus élevée. Dans ce cas, une association entre les cavités et les nanoprécipités (TiC et phosphures) est observée. Enfin une première comparaison entre les irradiations aux ions et aux neutrons sur le 15-15Ti D4 souligne de notables différences dans l'évolution de la précipitation et les mécanismes de formation des cavités. Un modèle de dynamique d'amas avec le code Crescendo permet de modéliser la formation des boucles de Frank, des cavités et l'évolution du réseau de dislocations et prend en compte la production d'hélium. Les paramètres du modèle ont été ajustés pour reproduire les données expérimentales des irradiations en simple faisceau à 630°C. L'extrapolation du modèle illustre le décalage du pic de gonflement vers les basses températures quand le taux de dommage diminue. Le modèle prenant en compte la présence de l'hélium reproduit l'augmentation de la densité de cavités observée en double faisceaux Fe-He / A cold-worked titanium stabilized austenitic steel, named 15-15Ti AIM1, is the reference material for fuel cladding to be used in the _rst core of ASTRID (prototype of Sodium cooled Fast neutron Reactor -SFR). This study contributes to the understanding of the microstructural evolution under high dose irradiation of AIM1 (> 100 dpa) and especially swelling mechanisms. Several ion irradiations of AIM1 and its precursor 15-15Ti D4 (AIM1 without phosphorus), were done at Jannus-Saclay facility. These irradiations were performed up to 150 dpa in single beam (Fe 2+) and up to 120 dpa in dual beams (Fe 2+ and He +) at a temperature set between 550 and 630 ° C in order to study the helium e_ects. Besides, thermal annealing at 650 ° Cequivalent to irradiation time (<100h) was carried out to separate the effects of temperature and irradiation. The microstructures and the irradiation-induced defects were characterized mainly by the transmission electron microscopy (TEM) and tomographic atom probe (SAT). During thermal annealing at 650 ° C, rapid precipitation of nanometric titanium carbides over dislocations was observed. A low density of phosphorus-enriched clusters (phosphide nucleation) was also detected. After irradiation with ions, the microstructure of AIM1 and 15-15Ti revealed high density of Frank faulted-loops distributed homogeneously and which didn'tevolve with the irradiation dose (between 45 and 150 dpa). The precipitation of nanometric titanium carbides, phosphides (in AIM1) and chromium carbides was observed. Precipitation of phosphides in AIM1 is accelerated by irradiation. Irradiation_induced segregation of Ni and Si on dislocations has also been highlighted. Single-beam irradiations even at 150 dpa show very low cavities density distributed heterogeneously in the grains. It is shown that the simultaneous injection of 1 appm / dpa helium leads to much higher cavity density. In this case, cavities are attached to nanoprecipitates (TiC and phosphides). Finally, a comparison between ion and neutron irradiation on 15-15Ti D4 highlighted significant differences in the evolution of precipitation and cavity formation mechanisms. A cluster dynamics model with the Crescendo code was used to simulate the formation of Frank loops, cavities and the evolution of the dislocation network, taking into account the helium production. The model parameters were adjusted to reproduce the experimental single beam irradiation data at 630°C. The extrapolation of the model shows the displacement of the swelling peak at low temperatures as the rate of damage decreases. Taking into account the presence of Helium, the model reproduces the increase of cavity density observed in double Fe-He beams.

En centrales nucléaires, un accident grave est une séquence très peu probable d’événements durant laquelle des composants du réacteur sont significativement endommagés, par interactions chimiques et/ou fusion, à cause de très hautes températures. Cela peut mener à des rejets radiotoxiques dans l’enceinte et à une entrée d’air dans le réacteur. Dans ce contexte, ce travail de thèse mené chez EDF R&D visait à modéliser la détérioration du gainage combustible, en alliages de zirconium, en conditions accidentelles : haute température et soit vapeur soit mélange air-vapeur. L’objectif final était d’améliorer la simulation par le code MAAP de l’oxydation du gainage et de la production d’hydrogène, en particulier pendant un renoyage avec de l’eau. Dû à l’épaississement progressif d’une couche de ZrO2 dense et protectrice, la cinétique d’oxydation du Zr en vapeur à hautes températures est généralement (sous-)parabolique. Cependant, à certaines températures, cette couche d’oxyde peut se fissurer, devenant poreuse et non protectrice. Par ce processus de « breakaway », la cinétique d’oxydation devient plus linéaire. De plus, l’augmentation de température peut mener les matériaux du réacteur à fondre et à se relocaliser dans le fond de cuve dont la rupture peut induire une entrée d’air dans le réacteur. Dans ce cas, l’oxygène et l’azote réagissent avec les gaines pré-oxydées, successivement par oxydation du Zr (épaississant la couche de ZrO2), nitruration du Zr (formant des particules de ZrN) et oxydation du ZrN (créant de l’oxyde et relâchant de l’azote). Ces réactions auto-entretenues relancent la fissuration du gainage et de sa couche de ZrO2, induisant une hausse de sa porosité ouverte. Afin de quantifier cette porosité du gainage, un protocole expérimental innovant en deux étapes a été défini et appliqué : il consistait à soumettre des échantillons de gainage en ZIRLO® à diverses conditions accidentelles pendant plusieurs durées puis à des mesures de la porosité ouverte par porosimétrie par intrusion de mercure. Les conditions de corrosion comprenaient plusieurs températures allant de 1100 à 1500 K ainsi que de la vapeur et un mélange air-vapeur 50-50 mol%. Pour les échantillons de ZIRLO® oxydés en vapeur, sauf à 1200 et 1250 K, les transitions de cinétique n’ont pas lieu et la porosité ouverte reste négligeable au cours de l’oxydation. Cependant, pour les autres échantillons, corrodés en air-vapeur ou oxydés en vapeur à 1200 ou 1250 K, des transitions « breakaway » sont observées et les résultats de porosimétrie montrent que la porosité ouverte augmente au cours de la corrosion, proportionnellement au gain en masse. De plus, il a été mis en évidence que la distribution de tailles de pores des échantillons de ZIRLO® s’étend significativement pendant la corrosion, en particulier après « breakaway ». En effet, ces tailles vont de 60 μm à environ : 2 μm avant la transition, 50 nm juste après et 2 nm plus longtemps après. Enfin, un modèle numérique en deux étapes a été développé dans le code MAAP pour améliorer sa simulation de l’oxydation du gainage. D’abord, grâce à la proportionnalité entre porosité ouverte et gain en masse des échantillons, des corrélations de porosité ont été implémentées pour chaque condition de corrosion. Ensuite, les valeurs de porosité calculées sont utilisées pour augmenter proportionnellement la vitesse d’oxydation du gainage. Ce modèle amélioré simule ainsi non seulement les réactions chimiques des gaines en Zr (oxydation et nitruration) mais aussi leur dégradation mécanique et son impact sur leur vitesse d’oxydation. Ceci a été validé en simulant des essais QUENCH (-06, -08, -10 et -16), conduits au KIT pour étudier le comportement de gaines dans des conditions accidentelles avec un renoyage final. Ces simulations montrent un meilleur comportement thermique du gainage et une production d’hydrogène significativement plus haute et donc plus proche des valeurs expérimentales, en particulier pendant le renoyage. / In nuclear power plants, a severe accident is a very unlikely sequence of events during which components of the reactor core get significantly damaged, through chemical interactions and/or melting, because of very high temperatures. This may potentially lead to radiotoxic releases in the containment building and to air ingress in the reactor core. In that context, this thesis work led at EDF R&D aimed at modeling the deterioration of the nuclear fuel cladding, made of zirconium alloys, in accidental conditions: high temperature and either pure steam or air-steam mixture. The final objective was to improve the simulation by the MAAP code of the cladding oxidation and of the hydrogen production, in particular during a core reflooding with water. Due to the progressive thickening of a dense and protective ZrO2 layer, the oxidation kinetics of Zr in steam at high temperatures is generally (sub-)parabolic. However, at certain temperatures, this oxide layer may crack, becoming porous and not protective anymore. By this “breakaway” process, the oxidation kinetics becomes rather linear. Additionally, the temperature increase can lead core materials to melt and to relocate down to the vessel lower head whose failure may induce air ingress into the reactor core. In this event, oxygen and nitrogen both react with the pre-oxidized claddings, successively through oxidation of Zr (thickening the ZrO2 layer), nitriding of Zr (forming ZrN particles) and oxidation of ZrN (creating oxide and releasing nitrogen). These self-sustained reactions enhance the cracking of the cladding and of its ZrO2 layer, inducing a rise of its open porosity.In order to quantify this cladding porosity, an innovative two-step experimental protocol was defined and applied: it consisted in submitting ZIRLO® cladding samples first to various accidental conditions during several time periods and then to measurements of the open porosity through porosimetry by mercury intrusion. The tested corrosion conditions included numerous temperatures ranging from 1100 up to 1500 K as well as both pure steam and a 50-50 mol% air-steam mixture. For the ZIRLO® samples oxidized in pure steam, except at 1200 and 1250 K, the “breakaway” kinetic transitions do not occur and the open porosity remains negligible along the oxidation process. However, for all other samples, corroded in air-steam or oxidized in pure steam at 1200 or 1250 K, “breakaway” transitions are observed and the porosimetry results show that the open porosity increases along the corrosion process, proportionally to the mass gain. Moreover, it was evidenced that the pore size distribution of ZIRLO® samples significantly extends during corrosion, especially after “breakaway” transitions. Indeed, the detected pore sizes ranged from 60 μm down to around: 2 μm before the transition, 50 nm just after and 2 nm longer after. Finally, a two-step numerical model was developed in the MAAP code to improve its simulation of the cladding oxidation. First, thanks to the proportionality between open porosity and mass gain of cladding samples, porosity correlations were implemented for each tested corrosion condition. Second, the calculated porosity values are used to proportionally enhance the cladding oxidation rate. This improved model thus simulates not only chemical reactions of Zr-based claddings (oxidation and nitriding) but also their mechanical degradation and its impact on their oxidation rate. It was validated by simulating QUENCH tests (-06, -08, -10 and -16), conducted at KIT to study the behavior of claddings in accidental conditions with a final reflooding. These simulations show a better cladding thermal behavior and a hydrogen production significantly higher and so closer to experimental values, in particular during the reflooding.

Gegenstand der Dissertationsschrift ist eine Darstellung des gegebenen Wissensstandes zum Scherschneiden anhand der Literatur, mit einer Einordnung des Schrägschneidens. Auf dieser Grundlage erfolgt eine Verfahrens- und Prozeßbeschreibung des Schrägschneidens, als Variante des Scherschneidens, insbesondere eine Untersuchung des auftretenden Verschleisses. Es wird die Anwendung des Laser-Pulver-Auftragschweißen an Schneidwerkzeugen zur Verschleißminimierung erprobt und bewertet.:1. Einleitung 2. Systematisierung von Profilen und Rohren 3. Herstellung von Profilen und Rohren 3.1. Fertigung von Profilen und Rohren 3.2. Trennen von Profilen und Rohren 4. Zerteilen – Stand der Technik 4.1. Systematik der Zerteilverfahren 4.2. Scherschneiden von Feinblechen 4.2.1. Schneidspalt und Schnittflächenqualität 4.2.2. Schneidkraft Scherschneiden im vollkantigen Schnitt Scherschneiden im kreuzenden Schnitt, Schrägschneiden 4.2.3. Werkzeugverschleiß 4.2.4. Schneidgeschwindigkeit 4.3. Beschichtungen an Werkzeugen zum Schneiden 5. Zielstellung und Inhalt der Arbeit 6. Scherschneiden von Leichtbauprofilen und –rohren 6.1. Schneidvorgang 6.2. Werkzeugaufbau 6.3. Auslegung von Scherschneidwerkzeugen für Leichtbauprofile und –rohre 6.4. Versuche zum Scherschneiden mit Schneidmessern von Leichbauprofilen und –rohren 6.4.1. Schneidspalt und Schnittflächenqualität 6.4.2. Schneidkraft und Schneidkraftverlauf 6.4.3. Werkzeugverschleiß 7. Laser-Pulver-Auftragsschweißen hartstoffverstärkter Verschleißschutz- schichten auf Schneidflächen von Schneidmessern 7.1. Laser-Pulver-Auftragschweißen 7.2. Werkstoffe 7.2.1. Grundmaterial 7.2.2. Zusatzwerkstoffe/Hartstoffe 7.2.3. Versuche zum Laser-Pulver-Auftragschweißen an Schneidflächen von Schneidmessern 7.3. Versuche zum Schrägschneiden mit hartstoffverstärkten Verschleißschutzschichten 8 Vergleich und Bewertung der Beschichtungssysteme 9. Zusammenfassung und Ausblick Anhang Literaturverzeichnis Abbildungsverzeichnis Tabellenverzeichnis

This diploma thesis deals with construction-technological project of production and storage hall in Hradec Králové. The thesis deals with complex of the implementation of the construction and focuses in more detail on the implementation of both foundation structures and assembly of the steel frame. The project includes a technical report on the construction technology project, a study of the implementation of the main technological stages of the main building, design and assessment of construction routes, construction equipment project, financial and construction schedule, machine design, schedule and budget of the main building, control and test plan for foundation structures, and occupational safety and health.

This diploma thesis deals with construction technology project of a newly-built automotive industrial hall on the complex Hauk – Police nad Metují. The aim of the main construction object is to build a double aisle steel hall for industrial purposes including maisonette built-in which will become social and technical facility for prospective workers. The main construction facility is complemented by secondary structures, creating functional complex for required purposes. The thesis is focused on implementation of the main load-bearing prefabricated steel structure and cladding made of selected system. An integral part of the thesis include main technology phases realization study of the main construction object, a technological prescription filled-in with assembly drawings, a design of machine assembly including dealing with its transportation, a site equipment project, time schedules, a budget, a test and inspection plan and a security measures design for selected risks. The thesis is suplemented by a specialized section dealing with the heating of reinforced landscaping.

The subject of this master thesis is the elaboration of project documentation for the construction of a car showroom & service. This building is located in Brno, cadastral area of city Brno: Královo Pole. It is a detached building without a basement built on a trapezoid shaped area with a flat terrain. Object is divided into two functional parts: the car showroom and the car service. These two parts are constructionally and operationally connected. The car showroom is designed as a two-storey object, which serves as car exhibition, technical and hygienic facilities and mainly the administrative parts of both objects. The car service is designed as a single-storey object without a basement, which serves as a workspace of the car service and a warehouse. The load-bearing structural system of the car showroom is made of reinforced concrete pillars with ceramic masonry. The load-bearing structural system of the car service is made of reinforced concrete pillars with light sandwich panels. The foundation slab consists of prefabricated stepped foundation pad, prefabricated reinforced concrete grade beam and concrete strip footing. Insulation system of the building is made of insulation boards from basalt wool cladding by ventilated facades with perforated steel panels. Insolation in the car showroom is secured by glass curtain wall in combination with plastic windows and doors. Ceiling structures are designed as prestressed ceiling panels Spiroll. Roofing structure of both objects is supported by prestressed reinforced concrete roof girder in combination with trapezoidal sheet and insulation boards from basalt wool and PIR boards. The roof of the objects is flat with ordinary layer order with waterproof layer from softened PVC.

The nuclear industry has long relied upon bounding parametric analyses in predicting the safety margins of reactor designs undergoing design-basis accidents. These methods have been known to return highly-conservative results, limiting the operating conditions of the reactor. The Best-Estimate Plus Uncertainty (BEPU) method using a modernized version of the Code-Scaling, Applicability, and Uncertainty (CSAU) methodology has been applied to more accurately predict the safety margins of the Oregon State University Advanced Plant Experiment (APEX) facility experiencing a Loss-of-Feedwater Accident (LOFA). The statistical advantages of the Bayesian paradigm of probability was utilized to incorporate prior knowledge when determining the analysis required to justify the safety margins. RELAP5 Mod 3.3 was used to accurately predict the thermal-hydraulics of a primary Feed-and-Bleed response to the accident using assumptions to accompany the lumped-parameter calculation approach. A novel coupling of thermal-hydraulic and statistical software was accomplished using the Symbolic Nuclear Analysis Package (SNAP). Uncertainty in Peak Cladding Temperature (PCT) was calculated at the 95/95 probability/confidence levels under a series of four separate sensitivity studies. / Graduation date: 2013

The subject of the diploma thesis is the architectural study of the mix-used urban housing situated closed to the Brno city centre. The design will allow mixing of greater amount of different functions on a relatively small built-up area, which will reduce the requirements on transport and provide the inhabitant with various forms of housing, services and employment. The mass and spatial solution respects the surrounding city blocks on south and the mass increase to the north industrial zone. The mass defines the area and respect noise protection zone on housing development. The shape of object's ground plan is based on the area, which is divided by four axes of pedestrian paths. The basic matter of object is divided into four blocks linked by common internal square. The mass solution provides private, semi-private and public courtyards.

The master´s thesis elaborates the project documentation for the construction of the District Police of the Czech Republic in Brno. The new building is situated in the north of city part Bohunice. It´s a three- floor object with partial basement and flat roof. The bearing perimeter masonry, internal bearing masonry and internal non- load bearing masonry are made with technology from ceramic hollow blocks. Ceiling construction is designed from prestressed ceiling panels. The perimeter walls of the of the underground floor are made from blocks of lost formwork, which is insulated with extruded polystyrene. The walls on the above- ground floors are insulated by a combination of contact thermal insulation system and ventilated facades with fiber- cement facade cladding boards.

This diploma thesis deals with a project of an sports relaxation centre in Havlíčkův Brod Ledečská street on plots no. 561/1 and 664/17 that are slightly sloping. The building is non-basement with 2 above-ground floors. The exterior load-bearing walls are made of clay blocks complemented with thermal insulation system according to ETICS. The building foundations are designes as strip foundations from concrete. Horizontal load-bearing structures will be made of prestressed concrete floor slab Spiroll. The building is roofed with a warm flat roof. First ground floor consists of sport part, there are big and small gym, crossfit excercise hall, 3 excercises halls for group lessons and 2 squash courts. It is also possible to use workout playground which is approached from the gym. There is also a buffet near the entrance. Second ground floor serves for relaxation, there are salt cave, sauna world with 5 different saunas (Finnish and also steam) and Whirlpool. The sauna world has also a cooling pool. Visitors can also use the outdoor rest area with a cooling pond. There are also a massage room, pedicure/manicure, solarium and sports shop.