Cette thèse présente une étude expérimentale et numérique d'essais de chute libre et de vibrations aléatoires d'emballages en carton ondulé contenant différents calages en mousse. Un modèle d'homogénéisation efficace pour le carton ondulé a été développé. Dans ce modèle homogénéisé, le carton ondulé est représenté par une plaque 2D. Au lieu d'utiliser une loi de comportement locale (reliant les déformations aux contraintes) à chaque point d'intégration, l'homogénéisation conduit aux rigidités globales (reliant les déformations généralisées aux forces résultantes) pour la plaque équivalente homogène. Ce modèle a été implémenté dans le logiciel Abaqus. Le comportement de la mousse a été déterminé expérimentalement et modélisé avec un modèle de mousse déformable d'Abaqus. Les emballages sont soumis à des tests de chute libre d'une hauteur donnée sur un sol rigide et des essais de vibrations aléatoires type bruit blanc sur table vibrante. Les résultats numériques obtenus en utilisant la simulation avec le modèle homogénéisé concordent bien avec les résultats expérimentaux. Nous avons également montré que la contribution de la caisse en carton ondulé à la réponse au choc et à la vibration aléatoire ne pouvait pas être négligée dans la conception des calages. / This thesis presents experimental and numerical studies of drop tests random vibrations of corrugated cardboard packaging containing different foam cushions. An efficient homogenization model for the corrugated cardboard has been developed. In this homogenized model, the corrugated cardboard is represented by a 2D plate. Instead of using a local constitutive law (relating the strains to the stresses) at each material point, the homogenization leads to global rigidities (relating the generalized strains to the resultant forces) for the equivalent homogeneous plate. This model was implemented into the FE software Abaqus. The foam behaviour was experimentally determined and modelled using a crushable foam model of Abaqus. The packages are tested in free fall from a given height on a rigid floor and submitted to white noise random vibrations. The numerical results obtained using the FE simulation with the homogenized model agree well with the experimental results. We have also shown that the contribution of the corrugated cardboard box to the shock and random vibration responses could not be neglected in the design of cushioning package.

Cílem této práce je návrh pevného tříkolového podvozku pro jednomotorový čtyřmístný celokompozitní letoun s dodržováním certifikačních specifikací CS-23. To zahrnuje návrh kompozitních pružinových hlavních podvozkových vzpěr v kombinaci s hydropneumatickým tlumičem příďového podvozku. Proces návrhu se dělí do pěti specifických fází; požadavky na konstrukci, předběžný návrh, detailní návrh, příprava výroby a zkoušení prototypu. Zatížení podvozku pro jednotlivé případy a konfigurace letounu je definován v předběžné fázi návrhu. Detailní návrh zahrnuje pevnostní analýzu jednotlivých komponentů. Fáze zkoušení prototypu definuje způsob ověření únosnosti zkouškou. Závěr obsahuje podrobnou technickou dokumentaci.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-20T17:21:11Z No. of bitstreams: 1 CamillaDeMedeirosDantasAzevedo_TESE.pdf: 4219113 bytes, checksum: 435317fad552ba84e55910c905f4e93f (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-22T12:38:32Z (GMT) No. of bitstreams: 1 CamillaDeMedeirosDantasAzevedo_TESE.pdf: 4219113 bytes, checksum: 435317fad552ba84e55910c905f4e93f (MD5) / Made available in DSpace on 2018-03-22T12:38:32Z (GMT). No. of bitstreams: 1 CamillaDeMedeirosDantasAzevedo_TESE.pdf: 4219113 bytes, checksum: 435317fad552ba84e55910c905f4e93f (MD5) Previous issue date: 2017-10-10 / As propriedades mec?nicas dos materiais comp?sitos, das mais diversas aplica??es industriais, podem ser reduzidas significativamente pela ocorr?ncia de impactos de baixas velocidades. Esses impactos podem provocar danos internos no material comprometendo sua integridade. Assim, o presente estudo tem como objetivo fazer uma an?lise experimental da resist?ncia residual ? flex?o em tr?s pontos e compress?o ap?s o impacto (CAI), de dois tipos de laminados comp?sitos de matriz polim?rica ortoft?lica, sendo um deles refor?ado a com 7 camadas de tecido bidirecional de Vidro E (CV) e o outro refor?ado com 7 camadas de tecido bidirecional de Kevlar 49 (CK), sujeitos a impactos de baixa velocidade. Esse estudo ? de grande import?ncia pelo fato de tentar conduzir ao aparecimento prematuro de instabilidade estrutural e a consequente restri??o do seu uso. A energia utilizada nesse trabalho para os dois tipos de laminados foi de aproximadamente 96J. Al?m disso, para o material comp?sito refor?ado com fibra de kevlar, foram feitos sucessivos impactos com a mesma energia verificando sua influ?ncia nas propriedades do laminado. Sendo aplicadas 5 vezes, e 10 vezes a energia m?xima de 96J. Como resultado verificou-se que no laminado CV, tanto as propriedades de compress?o como de flex?o em tr?s pontos, a resist?ncia se manteve praticamente inalterada enquanto que o m?dulo teve uma diminui??o depois do impacto. J? no laminado CK houve um decr?scimo tanto nas propriedades de compress?o como flex?o em tr?s pontos ap?s o impacto. Essa perda da integridade desses materiais pode ser justificada pela ocorr?ncia de delamina??o nas interfaces dos comp?sitos. / The mechanical properties of the composite materials, used in the most diverse industrial applications, can be significantly reduced by the occurrence of low speed impacts. These impacts can cause internal damage to the material and compromise its integrity. Thus, the present study aims to perform an experimental analysis of the residual resistance to three-point flexural test and compression after impact (CAI), in two types of composite laminates of orthophthalic polymeric matrix, being one of them reinforced with 7 layers of E-Glass bidirectional tissue (CV) and the other reinforced with 7 layers of Kevlar 49 bidirectional tissue (CK), subject to low speed impacts. This study is of great importance because it tries to lead to the premature appearance of structural instability and the consequent restriction of its use. The energy used in this work for the two types of laminates was approximately 96J. In addition, for the Kevlar fiber reinforced composite material, were made successive impacts with the same energy being checked its influence on the properties of the laminate, where it was tested with a repetition of 5 times and 10 times the maximum energy of 96J.As result, it was found that in the CV laminate, both in the compression properties and three-point flexural properties, the resistance remained practically unchanged while the modulus had a decrease after impact. In the CK laminate, there was a decrease both in compression properties and three-point flexural properties after impact. This integrity loss of these materials can be justified by the occurrence of delamination at the interfaces of the composites.

This master thesis focuses on a scaled fuselage design made from composite material. The first part deals with a description of composite materials and used material models in an explicit FEM simulation. Two types of scaled structures were designed that were subjected to drop test. Test results were compared with FEM simulation. Finally the calibration of models was carried out.

There is a high demand for implementing simulations in the design and product devel-opment processes, avoiding the execution of costly tests on prototypes and giving thechance of discarding unsuitable designs, as well as exploring possible ones without much cost added.This project assignment is to find a suitable way to simulate drop tests on two typesof PMMA sheets, a material widely used on luminaire covers. Therefore, it becomesnecessary to study the mechanical behavior of these materials, using experimental tests,in order to calibrate the material models used in the simulations.During the experimental testing, common polymer behaviors were found on the twostudied materials, such as rate dependence, non-linear elasticity, viscoelasticity and vis-coplasticy. Behaviors which presented several challenges regarding the choice and cali-bration of the material models.The two di?erent polymers were calibrated for the simulations using two di?erentmaterial models. An elastic-plastic (Drucker Prager Plasticity) model was used for oneof the materials, whereas an hyperelastic-viscoelastic model was used for the other one.Finally, several drop tests simulations were conducted and compared with experimentaltests

Polydimethylsiloxan (PDMS)-basierte Materialien finden Verwendung als Schirmmaterial für Verbundisolatoren in der Hochspannungstechnik. Diese Schirmmaterialen benötigen im Außeneinsatz eine herausragende Hydrophobie, um Spannungsüberschläge durch leitfähige Elektrolytfilme zu vermeiden. Im Außeneinsatz widerfährt ein Schirmmaterial unterschiedliche Witterungsbedingungen wie z.B.: Regen oder Betauungsvorgänge. Unter Wirkung hoher elektrischer Felder können dann auf der Oberfläche Tropfenteilentladungen auftreten, die zu einer Hydrophilisierung der Oberfläche führen. Ziel der Arbeit ist es die Materialparameter zu beleuchten, die einen Einfluss auf die Hydrophobiebeständigkeit von Schirmmaterialien besitzen. Kommerziell erhältliche Silikon-Komposite besitzen neben dem eigentlichen Silikonnetzwerk auch Füllstoffe in unbekannter Art und Konzentration, wodurch eine Ursachenfindung für den Hydrophobieverlust erschwert ist. Aus diesem Grund wurde auf eigens synthetisierte Silikonelastomere zurückgegriffen. Diese wurden durch platinkatalysierte Hydrosilylierungsreaktion aus vinylterminierten PDMS (vPDMS) und dem tetrafunktionalem Vernetzer Tetrakis(dimethylsiloxysilan) (TDSS) hergestellt. Durch Variation der Kettenlängen des vPDMS und durch Variation des stöchiometrischen Verhältnisses konnte ein vPDMS-TDSS-Modell-Silikonsystem entwickelt werden, worin Netzwerkparameter (Netzwerkdichte und Sol-Anteil) gezielt justiert werden konnten. Die hergestellten Silikonelastomere wurden anschließend hinsichtlich ihrer Hydrophobie untersucht und im Anschluss gegenüber ihrer Beständigkeit gegenüber Tropfenteilentladungen getestet. Zur Simulation der kombinierten elektrischen und elektrolytischen Beanspruchung wurden dynamische Tropfentests durchgeführt, um die Hydrophobiebeständigkeit zu untersuchen. Im Rahmen der Arbeit wurde festgestellt, dass insbesondere die Steifigkeit der Materialien einen wesentlichen Einfluss auf die Hydrophobiebeständigkeit von Silikonen hat. Zusätzlich beeinflusst die Rauheit eines Materials die Ausfallzeiten im dynamischen Tropfentest maßgeblich. Darüber hinaus führt ein überlagerter Ölfilm auf der strukturierten Oberfläche dazu, dass sich das Abgleitverhalten von Wassertropfen im Laufe der Zeit verändert.

Paper and pulp industry and steel industry are two major industries in Sweden, both of which are facing big challenges to treat their waste products properly. In this thesis work, initial evaluation of mechanical properties of briquettes made of waste products was performed. Three different CaO-containing waste products (Mesa, Kalk, Fly Ash) from Stora Enso and SCA were pressed with one kind of binding material (AOD slag) from Outokumpu. Drop tests were carried out to test the impact strength of the lab-made briquettes. Three different parameters were investigated of their influence on the impact strength of the briquettes: 1) Composition of briquettes 2) Heat treatment procedure 3) Exposure time to open air. A total of 97 briquettes were pressed. Drop test results show that for different material based briquettes, heat-treatment and exposure to open air had different influence on the final impact strength. In order to get best impact strength, MB briquettes (90% Mesa +10% AOD slag) heat treated at 850℃, KB briquettes (90% Kalk +10% AOD slag) heat treated at 850℃ and FC briquettes (80% Fly Ash + 20% AOD slag) exposed to open air for 20 days are recommended. Melting experiment was carried out to investigate the sulphur removal ability of the briquettes in metallurgical processes. Thermodynamic calculation of sulphide capacity was done. / Pappers-, massa och stålindustrin är två stora industrier i Sverige, vilka båda står inför stora utmaningar för att hantera sina avfallsprodukter på rätt sätt. I denna avhandling utfördes en första utvärdering av mekaniska egenskaper hos briketter av avfallsprodukter. Tre olika CaO- innehållande avfallsprodukter (Mesa, Kalk, Fly Ash) från Stora Enso och SCA pressades med ett   bindande   material   (AOD   slagg)   från   Outokumpu.   Dropptest   utfördes   för   att   testa slaghållfastheten hos de laboratoriegjorda briketterna. Tre  olika  parametrar  undersöktes  av  deras  påverkan  på  briketternas  slaghållfasthet:  1) Brikets sammansättning 2) Värmebehandlingsförfarande 3) Exponeringstid för friluft. Totalt 97 briketter pressades. Dropptestresultat visar att för olika materialbaserade briketter hade värmebehandling   och   exponering   för   utomhusluft   ett   annat   inflytande   på   den   slutliga slagstyrkan.  För  att  få  bästa  slaghållfasthet,  värmebehandlades  MB-briketter  (90%  Mesa  + 10% AOD-slagg) värmebehandlad vid 850 ° C, KB-briketter (90% Kalk + 10% AOD-slagg) vid 850  °  C  och  FC-briketter  (80%  Fly  Ask  +  20%  AOD  slagg)  utsatt  för  öppen  luft  i  20  dagar rekommenderas. Smältningsexperiment utfördes för att undersöka svavelfjernningsförmågan hos briketterna imetallurgiska processer. Termodynamisk beräkning av sulfidkapacitet gjordes.

Today, a huge part of waste products from pulp and paper industries ends up in landfill which is both economically and environmentally adversely. This report examines the possibilities of using those products as a slag foamer and fuel in different furnaces in the metal industry. The waste products contain valuable elements, especially carbon. Therefore, there is an increased interest in finding possible use for the waste products in the metal industry. The reuse would contribute to preservation of energy as fossil fuel can be replaced. In the report, two waste materials called mixed biosludge and fiber reject are examined. The experiments are performed with the waste products pressed together with a base material and cement forming a briquette. The requirements examined are strength needed for both transportation and use in furnaces and ability to create a foaming slag. The results in strength were ambiguous, no waste material based briquettes met the set criteria. As of now, the briquettes are probably not strong enough to be transported. No foaming occurred during the experiment, but only one experiment was performed. Therefore, further experiments are needed before any conclusions can be drawn. The briquettes can possibly replace coke and coal in applications where strength is not as important. Nevertheless, it is uncertain if the briquettes affect the steel quality. / Idag läggs en stor del av restprodukter från pappers och massaindustrin på deponi, vilket innebär såväl ekonomiska som miljömässiga nackdelar. Den här rapporten undersöker möjligheterna att använda dessa restprodukter som slaggskummare och bränsle i de olika ugnarna inom metallindustrin. Restprodukterna innehåller värdefulla ämnen, framförallt kol. Därför finns det ett ökat intresse för att hitta möjliga användningsområden för restprodukterna inom metallindustrin. Denna återanvändning skulle bidra till energibevarande eftersom fossila bränslen kan ersättas. I den här rapporten undersöks två restmaterial, blandat biologiskt slam och fiberavfall. Experimenten utfördes med dessa restprodukter pressade samman med ett basmaterial och cement till en brikett. Kraven som undersöks är styrka för både transport och användning i ugnarna samt förmågan att skumma en slagg. Resultaten för briketternas styrka var tvetydiga, inga av briketterna innehållande restprodukter satisfierade det uppsatta kriteriet. Styrkan är troligtvis för låg för att transport ska vara möjlig. Ingen skumning skedde under experimentet, men endast ett experiment genomfördes. Därför behöver ytterligare experiment genomföras innan några slutsatser kan dras. Men briketterna tros kunna ersätta koks och kol där styrkan inte är viktig. Men det är osäkert om briketterna påverkar stålkvaliteten.

Cette étude constitue une contribution dans un grand projet européen dénommé : 3DICE (3D Integration of Chips using Embedding technologies). La fiabilité mécanique et thermomécanique des composants 3D a été étudiée par des essais normalisés et des simulations numériques. L’essai de chute et le cyclage thermique ont été sélectionnés pour la présente étude. Des analyses de défaillance sont menées pour compléter les approches expérimentales. Les propriétés mécaniques des éléments constituant les composants ont fait l’objet d’une compagne de caractérisation complétée par des recherches bibliographiques. Les simulations numériques, dynamiques transitoires pour l’essai de chute et thermomécanique pour l’essai de cyclage thermique, ont été réalisées pour une estimation numérique de la tenue mécanique des composants. Les modèles numériques sont utilisés pour optimiser le design des composants et prédire les durées de vie en utilisant un modèle de fatigue. / This work establishes a contribution in an important European project mentioned 3DICE (3D Integration of Chips using Embedding technologies). The mechanical and thermomechanical reliability of 3D microelectronic components are studied by employing standardized tests and numerical modeling. The board level drop test and thermal cycling reliability tests are selected for this study. Failures analysis has been used to complete the experimental study. The mechanical properties of elements constituting the microelectronic components were characterized using DMA, tensile test and nanoindentation. Bibliographical researches have been done in order to complete the materials properties data. Numerical simulations using submodeling technique were carried out using a transient dynamic model to simulate the drop test and a thermomechanical model for the thermal cycling test. Numerical results were employing in the design optimization of 3D components and the life prediction using a fatigue model.

Forklifts that are capable of lifting heavy loads and reaching high lift heights are required by stan-dards to have an overhead guard to protect the operator from falling objects. The same standardsspecify a standardized procedure for testing the strength of these overhead guards. The test in-volves dropping ten 45 kg wooden cubes and a heavy timber load onto the overhead guard. Thesedestructive tests are time-consuming and expensive, and it is the purpose of this master’s thesis todevelop a methodology for simulating this kind of test using the finite element method with a largedisplacements, explicit scheme using the solver RADIOSS by Altair. This was achieved by firstdesigning, constructing, and testing a physical prototype of an overhead guard to use as a referencefor a finite element methodology to be validated against. The work has also included tensile testingof the overhead guard material, and this was done both to obtain material data from the sametype of material as the prototype, and to get Johnson-Cook material parameters, which are hardto come by in the literature. Next, a basic finite element model was created which showed a verylarge discrepancy compared to the physical test results. An extensive investigation into aspectssurrounding finite element modeling and material modeling was undertaken, and resulted in a fi-nal model which overestimated the displacements by about 40 % only. The remaining inaccuracyis believed to mostly stem from inadequate strain-rate sensitivity data, caused by limitations inavailable resources for material testing.