A wall might appear as basic, a clean surface without an identity of its own, nothing but a clean slate upon which to leave any impression. Though the walls surrounding us are all but anonymous. They are built with a structure making them stand tall and strong. They are filled with insulation to keep us warm and sheltered. They are hard and they are soft. They can allow us to isolate ourselves from each other or they are fragile enough to let us know someone is on the other side. They cover the basic necessities of our houses, and we in return cover them to make our spaces less anonymous. There is softness hidden in your walls mainly aims to highlight the textile components of architecture which we usually never see. While we tend to view textiles mostly as decoration, they constantly perform in a lot of various ways all around us. In this project I have worked with prefabricated building materials that according to me have textile qualities, but they aren’t viewed as textile. Or I have tried to adapt textile techniques to non-textile materials to test them in new ways. The wall as the leading actor has first and foremost been used as a conversation partner for the material exploration and contextualization. The main material used is wool sheep insulation though many other materials have been put to the test throughout the process.

Product certificates are sent throughout the supply chain of Swedish heavy industry in order to show provenance and physical characteristics of objects such as screws. The data management of the certificates has been, and still is, a very manual process. The process requires extensive work in order to maintain a correct record of the certificates. In particular, tracing causes of errors and establishing compliance takes a long time and effort. The company Chaintraced is developing an application to automate the process by acting as a third party to digitalize and manage the certificates. Introducing a third party into a business-to-business process requires that data integrity is preserved and that information reaches its expected destination. Recent research has indicated that distributed ledger technologies showpromise to fulfill these requirements. In particular, blockchain-based systems offer immutability and traceability of data, and can reduce the trust needed between different parties by relying on cryptographic primitives and consensus mechanisms. This thesis investigates the application of distributed ledger technology to further automate the Swedish heavy industry supply chain and reduce the trust needed in a third party managing the certificates. Requirements for an industrial strength system is set up and several distributed ledger technology solutions are considered to fit the use case of Swedish heavy industry. A proof of concept based on the findings is implemented, tested and compared with a centralized database to explore its possible usage in the supply chain with regard to feasibility, immutability, traceability and security. The investigation resulted in a prototype based on Hyperledger Fabric to store product certificates. The solution provides certain guarantees to immutability and security while being developed with feasibility for deployment in mind. The proposed solution is shown to be slow compared to a centralized solution but scales linearly with number of certificates and is considered within bounds for the use case. The results also show that the proposed solution is more trustworthy than a centralized solution, but that adopting blockchain technology is an extensive task. In particular, trustworthiness and guarantees provided by the solution is highly dependent on the feasibility aspect and the investigation concludes that adoption of blockchain technology within the Swedish heavy industry must take this into consideration. / Hanteringen av produktcertifikat inom den svenska tungindustrin är en mycket manuell process vilket resulterar i att ett enormt arbete krävs för att upprätthålla en korrekt hantering av certifikaten. Att spåra orsaken till fel och att kontrollera efterlevnaden av krav inom industrin tar lång tid. Chaintraced har utvecklat en applikation som automatiserar hanteringen av certifikaten genom digitalisering och att som tredje part lagra informationen. Att introducera en tredje part i affärsverksamheter kräver att integriteten av datan bibehålls och att information anländer till korrekt mottagare. Ny forskning har visat att distribuerade liggare har möjligheten att uppfylla dessa krav. Framförallt gällande blockkedjetekniken med dess många egenskaper och garantier som företag letar efter, så som oföränderlig och spårbar data. Blockkedjetekniken reducerar också förtroendet som behövs för parter inom nätverket genom att förlita sig på kryptografi och konsensus mekanismer. Den här rapporten utreder användningen av distribuerade liggare för att ytterliggare automatisera den svenska tungindustrins leveranskedja och minska tilliten som krävs för en tredje part som hanterar certifikaten. Krav ställs upp för ett system och flertalet distribuerade databastekniker undersöks för att passa in i fallet angående den svenska tungindustrin. En prototyp är utvecklad baserad på kraven, prototypen är testad och jämförd med en central databas för att undersöka hur implementationen står sig vad gäller genomförbarhet, oföränderlighet, spårbarhet och säkerhet. Undersökningen resulterade i en prototyp baserad på Hyperledger Fabric. Prototypen lagrar produktcertifikaten och ger vissa garantier till oföränderligbarhet samt säkerhet. Möjligheten för aktörer i kedjan att använda prototypen hade stor inverkan på hur systemet utvecklades. Prototypen visar sig vara långsammare än en centraliserad lösning men mätningarna kan anses vara inom kraven för ett system inom tungindustrins leveranskedja. Skalbarheten av lösningen är beroende av kraven på säkerhet men är linjär i antalet certifikat som skickas och lagras. Resultaten visar också att den föreslagna lösningen inger mer tillit än en centraliserad lösning men att introducera blockkedjetekniken är en komplex process. Trovärdighet och garantier som ges av lösningen är till stor del beroende av komplexiteten vilket rapporten kommer fram till är det viktigaste för svensk tungindustri att ha i åtanke vid eventuell antagande av blockkedjeteknik.

Dagens textil- och modeindustri producerar stora mängder avfall och i produktionsfasen uppstår merparten av det vid tillskärning av mönsterdelar. FN har satt upp 17 globala mål för att främja en hållbar utveckling och mål nummer 12 fokuserar på att främja hållbar konsumtion och produktion. För att uppnå det är det därav relevant att utforska alternativ för att höja utnyttjandegraden av tyg vid tillskärningsstadiet inom konfektion. Studien utförs i samarbete med ett svenskt företag och undersöker hur enklare mönsterförändringar på en jacka kan påverka effektiviteten hos plaggets läggbild. Studien dokumenterar och analyserar resultatet av olika mönsterförändringar utförda på en jacka samtidigt som plaggets design behålls snarlik och sammanställer dess effekt på läggbildseffektiviteten samt tygåtgången. Tidigare forskning har fokuserat på effektivisering av läggbilder utan mönsterförändring alternativt mönsterkonstruktion baserad på idén om zero-waste pattern cutting vilket ämnat ett eliminera materialspill men inte minska tygåtgång. Rapportens fokus ligger vid effektivisering av läggbilder med hjälp av mönsterkonstruktion utifrån studiens aktuella plagg med ambitionen att uppnå materialbesparing. Studien presenterar åtta olika mönsterförändringar, dess effekter på tygåtgång och läggbildseffektivitet samt vilka parameter som bör tas hänsyn till vid omvandling av mönster för läggbildseffektivisering. / Today's textile and fashion industry produces large amounts of waste and in the production phase most of it arises when cutting pattern pieces. Goal number 12 of the UN's 17 Global Goals for Sustainable Development stands to promote sustainable consumption and production, and in order to achieve this, it is therefore relevant to explore alternatives for increasing the degree of utilization of fabric at the cutting stage in clothing production. The study is carried out in collaboration with a Swedish company and examines how simpler pattern changes on a jacket can affect the efficiency of the garment's lay plan. The study documents and analyzes the results of various pattern changes performed on a jacket while maintaining a similar design to that of the original garment and compiling its effect on the lay plans efficiency and fabric consumption. Previous research has focused on bettering the efficiency of lay plans without pattern change or pattern design based on the idea of zero-waste pattern cutting which aims to eliminate fabric waste but not cut down on fabric consumption. Focus of the report is on how to achieve higher efficiency in lay plans using pattern construction based on the study's chosen garment with the aim of saving fabric waste. The study presents eight different pattern changes, its effects on fabric consumption and lay plan efficiency and which parameters should be considered when transforming patterns for the purpose of increasing lay plan efficiency.

Granular materials are widely used as unbound layers within the infrastructure system playing a significant role on performance and maintenance. However, fields like pavement and railway engineering still heavily rely on empirically-based models owing to the complex behaviour of these materials, which partly stems from their discrete nature. In this sense, the discrete element method (DEM) presents a numerical alternative to study the behaviour of discrete systems with explicit consideration of the processes at particulate level governing the macroscopic response.  This thesis aims at providing micromechanical insight into the effect of different particle sizes on the load-bearing structure of granular materials and its influence on the resilient modulus and permanent deformation response, both of which are greatly influenced by the stress level. In order to accomplish this, binary mixtures of elastic spheres under axisymmetric stress are studied using DEM as the simplest expression for gap-graded materials, which in turn also can be seen as a simplification of more complex mixtures. First, the effect of the fines content on the force transmission at contact level was studied. Results were used to define a soil fabric classification system where the roles of the coarse and fine fractions were defined and quantified in terms of force transmission. A behavioural correspondence between numerical mixtures and granular materials was established, where the mixtures were able to reproduce some of the most significant features regarding the resilient modulus and permanent strain dependency on stress level for granular materials. A good correlation between soil fabric and performance was also found. Generally, higher resilient modulus and lower deformation values were observed for interactive fabrics, whereas the opposite held for instable fabrics. Mixtures of elastic spheres are far from granular materials, where numerous additional factors should be considered. Nevertheless, it is the author’s belief that this work provides insight into the soil fabric structure and its effect on the macroscopic response of granular materials. / Grus i form av krossat bergmaterial används i stor utsträckning som obundna bär- och förstärkningslager inom tranportinfrastrukturen och spelar där en viktig roll för verkningsätt, drift och underhåll. Det finns emellertid begränsad kunskap om de fundamentala mekanismerna på partikelnivå (d.v.s. enskilda gruskorn), mekanismer som styr det makromekaniska verkningssättet. Områden såsom väg- och järnvägsbyggnad bygger fortfarande väsentligen på empiriskta baserade modeller p.g.a. dessa materials komplexa uppträdande under belastning. Denna komplexitet beror delvis på den diskreta naturen hos problemet vilket innebär att traditionell matematisk modellering som vore materialen homogena och kontinuerliga, blir inadekvat. Mot denna bakgrund utgör den s.k. diskreta elementmetoden (DEM) ett numeriskt alternativ för att studera verkningssätt hos diskreta system där man explicit beaktar mekanismerna på partikelnivå. Denna avhandling, som baseras på tre vetenskapliga bidrag, syftar till att ge mikromekaniska insikter vad gäller effekten av olika partikelstorlekar på bärförmågan hos grusmateral och dess inverkan på styvhet och motstånd mot permanenta deformationer. Båda dessa parametrar påverkas kraftigt av spänningsnivån och kan studeras genom triaxialförsök. För att undersöka detta studerades med hjälp av DEM binära blandningar av elastiska kulor – den enklaste modellen av grusmaterial med språng i fördelningskurvan – som utsattes för axialsymmetrisk belastning. Denna modell kan i sin tur ses som en förenkling av mer komplexa blandningar. Inledningsvis studerades effekten av finpartikelinnehållet på partikelkontakternas kraftöverföring. Resultaten användes för att klassificera olika typer av skelettstrukturer i grusmaterialet där den finare och den grövre fraktionens roller kvantifierades med utgångspunkt från kraftöverföringen i stället för från det makromekaniska verkningssättet. Resultaten visade en korrelation vad gäller verkningssättet mellan numeriska blandningar och grusmaterial, där de numeriska blandningarna kunde reproducera några av grusmaterials viktigaste kännetecken vad gäller spänningsberoendet för styvheten vid avlastning och motståndet mot permanent deformation. Vidare visades att styvheten kunde bestämmas ur första belastningscykeln vilket underlättar att övervinna de begränsningar avseende beräkningstid som annars förknippas med DEM. God överensstämmelse mellan grusmaterialets skelettstruktur och verkningssätt kunde också observeras. Generellt observerades högre styvhet och mindre permanenta deformationer för interaktiva skelettstrukturer medan det motsatta gällde för instabila strukturer. Numeriska blandningar av elastiska kulor är långt från verkliga grusmaterial, för vilka ett stort antal ytterligare faktorer måste beaktas. Icke desto mindre är det författarens övertygelse att detta arbete ger insikter i grusmaterialets skelettstruktur och dess effekter på det makromekaniska verkningssättet hos grusmaterial. / <p>QC 20161116</p>

Construction sites are among the most common areas to experience soil erosion and sediment transport due to the mandatory foundation tasks such as excavation and land grubbing. Thus, temporary sediment barriers are installed along the perimeter to prevent sediment transport from the site. Erosion and sediment transport control measures may include, but not limited to, physical and chemical processes such as the use of a silt fence and polyacrylamide product. Runoff from construction sites and other impervious surfaces are routinely discharged into ponds for treatment before being released into a receiving water body. Stormwater harvesting from a pond for irrigation of adjacent lands is promoted as one approach to reducing pond discharge while supplementing valuable potable water used for irrigation. The reduction of pond discharge reduces the mass of pollutants in the discharge. In the dissertation, presented is the investigation of the effectiveness of temporary sediment barriers and then, development of a modeling approach to a stormwater harvesting pond to provide a comprehensive stormwater management pollution reduction assessment tool. The first part of the research presents the investigation of the performance efficiencies of silt fence fabrics in turbidity and sediment concentration removal, and the determination of flowthrough-rate on simulated construction sites in real time. Two silt fence fabrics, (1) woven and the other (2) nonwoven were subjected to material index property tests and a series of field-scale tests with different rainfall intensities and events for different embankment slopes on a tilting test-bed. Collected influent and effluent samples were analyzed for sediment concentration and turbidity, and the flow-through-rate for each fabric was evaluated. Test results revealed that the woven and nonwoven silt fence achieved 11 and 56 percent average turbidity reduction iv efficiency, respectively. Each fabric also achieved 20 and 56 percent average sediment concentration removal efficiency, respectively. Fabric flow-through-rates were functions of the rainfall intensity and embankment slope. The nonwoven fabric exhibited higher flow-throughrates than the woven fabric in both field-scale and laboratory tests. In the second part of the study, a Stormwater Harvesting and Assessment for Reduction of Pollution (SHARP) model was developed to predict operation of wet pond used for stormwater harvesting. The model integrates the interaction of surface water and groundwater in a catchment area. The SHARP model was calibrated and validated with actual pond water elevation data from a stormwater pond at Miramar Lakes, Miramar, Florida. Model evaluation showed adequate prediction of pond water elevation with root mean square error between 0.07 and 0.12 m; mean absolute error was between 0.018 and 0.07 m; and relative index of agreement was between 0.74 and 0.98 for both calibration and validation periods. The SHARP model is capable of assessing harvesting safe-yield and discharge from a pond, including the prediction of the percentage of runoff into a harvesting pond that is not discharged. The combination of silt fence and/or polyacrylamide PAM before stormwater harvesting pond in a treatment train for the reduction of pollutants from construction sites has the potential of significantly exceeding a performance standard of 85 percent reduction typically required by local authorities. In fact, the stringent requirement of equaling pre- and post-development pollutant loading is highly achievable by the treatment train approach. The significant contribution from the integration of the SHARP model to the treatment train is that real-time assessment of pollutant loading reduction by volume can be planned and controlled to achieve target performance standards.

The soil response in triaxial compression tests, that are commonly treated as element tests, is known to be inhomogeneous. Several studies have revealed the localisation of deformation throughout the whole specimen by digital image correlation techniques on X-ray tomographies. The fabric of a soil specimen has so far only been studied on complete specimens as a bulk measurement or in chosen subsets. In this contribution, we present a study on the spatial and temporal distribution of the fabric throughout one Hostun sand sample in triaxial compression. Therefore, we calibrated the minimum representative element size first for three chosen fabric variables considering three different criteria. By distributing the elements in a regular grid over the specimen, we are able to clearly identify the onset of the localisation in terms of void ratio, coordination number and contact fabric anisotropy. Spatially and temporally the contact fabric variables precede the void ratio changes as they are much more sensitive to small changes.

Исследовать материалы, используемые для усиления железобетонных балок, провести расчеты усиления балки в направлении действия изгибающего момента и поперечной силы с использованием композитных материалов с их технико-экономическим обоснованием. / Investigate the materials used to reinforce reinforced concrete beams, carry out calculations of the beam reinforcement in the direction of the bending moment and shear force using composite materials with their feasibility study.

Syntetiska material står idag för merparten av produktionskedjan för textilmaterial globalt. Behovet av biobaserade regenererade fibrer ligger i framkant när det gäller framtida val för produktion av textilmaterial i samband med målen för hållbar utveckling. I Sverige produceras upp till ca 1000 ton ull per år där endast 46% av ullen faktiskt bearbetas. Svensk gotland- och leicester ull har tidigare ansetts vara svåra att spinna till garn på grund av dess långa fibrer och låg filtbarhet. I och med att en stor del av textilindustrin förflyttades utomlands i slutet av 1960-talet försvann också delar av värdekedjan som då fanns tillgängliga för att möjliggöra förädling av den svenska ullen. Flera delar av den textila värdekedjan för svensk ull som saknats håller idag på att återuppbyggas och initiativ och projekt pågår för att utveckla och återupprätta den svenska ull- industrin. I detta arbete jämförs de två svenska ullkvaliteterna gotlands- och leicesterull och karakteriseras på fiber- och garnnivå utifrån sina textila egenskaper för tillverkning av vävt ulltyg, i syfte att användas som möbeltyg. Detta utförs genom att studera beteendet hos olika typer av bindningar i avseende på dess nötningsbeständighet, samt upphov till pilling och luddighet. Resultaten kopplas till de olika garnens styrkeegenskaper, där garner som innehåller leicesterull uppvisade en styrka på över 3000 cN vid brott, vilket visade sig vara högre än motsvarande resultat som erhållits av gotlandsullen. Vikten av bindningstyp som bör användas vid vävning av ulltyger belyses såväl som analysering av de effekterna som slutbehandlingar ger. Vid val av de olika bindningstyperna satin med olika stigningstal - varprips och halvpanama - som testats för sin prestanda, visade sig varprips och halvpanama vara väl lämpade för vävt möbeltyg av ull. Varpripsbindningens konstruktion visade att varptrådarna slits ut vid nötning medan väfttrådarna skyddas underifrån, vilket spelar roll för produktion och utveckling av tyger utifrån ekonomiska aspekter. Alla provkroppar klarade nötningsbeständighet upp till 50 000 varv enligt Martindale-metoden, med undantag för ytliga skador där satinen bildade noppor i ett tidigt skede och påvisade en högre risk till slitage. Dekatering som utfördes visade sig bidra till att ullväven erhöll en högre glans och högre dimensionsstabilitet och anses därmed vara en relevant slutberedning för ullväven. Svedning bidrog till en minskad ytluddighet som önskat. Tvättning i foulard gav bindningarna i väven högre stabilitet till följd av filtningsprocessen men resulterade däremot i en viss oönskad nyansskillnad. / Synthetic materials currently account for the majority of the textile material production chain globally. The need for bio-based regenerated fibers is at the forefront of future choices for the production of textile materials in the context of the Sustainable Development Goals. In Sweden, up to about 1000 tons of wool are produced per year where only 46% of the wool is actually processed. Swedish Gotland and Leicester wool has previously been considered difficult to spin into yarn due to its long fibers and low feltability. With the relocation of a large part of the textile industry abroad in the late 1960s, parts of the value chain that were then available to enable the processing of Swedish wool also disappeared. Several parts of the textile value chain for Swedish wool that were missing are now being rebuilt, and multiple initiatives and projects are underway to develop and restore the Swedish wool industry. In this work, the two Swedish wool qualities Gotland and Leicester wool are compared and characterized at the fiber and yarn level based on their textile properties for the production of woven wool fabric, with the aim of being used as upholstery fabric. This is done by studying the behavior of different types of bindings in terms of their abrasion resistance, pilling and linting. The results are linked to the strength properties of the different yarns, with yarns containing leicester wool exhibiting a strength of over 3000 cN at break, which proved to be higher than the corresponding results obtained from Gotland wool. The importance of the bonding type that should be used in the weaving of wool fabrics is highlighted as well as analyzing the effects of finishing treatments. In selecting the different types of satin weave with different pitches, warp faced rep and half-panama, which were tested for their performance, warp faced rep and half-panama proved to be well suited for woven wool upholstery fabrics. The design of the warp binding showed that the warp threads are worn out by abrasion while the weft threads are protected from below, which is important for the production and development of fabrics from an economic point of view. All specimens passed abrasion resistance up to 50 000 revolutions according to the Martindale method, with the exception of superficial damage where the satin formed nubs at an early stage and showed a higher risk of wear. Decatizing was found to contribute to a higher gloss and higher dimensional stability of the wool fabric and is thus considered a relevant final preparation for the wool fabric. Singeing contributed to a reduction in surface fuzziness as desired. Washing in the foulard gave the bonds in the fabric higher stability as a result of the felting process but also left a certain shade difference.

The majority of constitutive models, that are used nowadays to describe the behaviour of granular materials such as sands, are continuum models based on phenomenological approaches. In order to describe some of the phenomena occurring on the macroscopic scale, e.g., the abrupt change of stiffness due to a load reversal, constitutive models use phenomenological state variables (e.g., the inter-granular strain concept for hypoplasticity). These often lack a clear physical meaning. The mechanisms that control the macroscopic behaviour must be sought at the grain-scale with the interactions of individual particles playing the key-role. To access that scale and describe the fabric of granular assemblies, x-ray μ-computed tomography is used in this thesis for full-field measurements during monotonic and cyclic experiments. This non-destructive technique allows to acquire 3D images at various stages of the loading and thus, a tracking of the evolution of the fabric. The spatial resolution of such tomographies is limited as the specimen has to be mechanically representative and at the same time sufficiently small to identify individual grains in the images. Different image analysis techniques can be used to extract information on the fabric of the granular material, but they all lack a thorough metrological characterisation, especially regarding the limited spatial resolution. Therefore, it was necessary to study the different techniques and determine their uncertainties before running the experiments and evaluating the tomographies. Artificial as well as high resolution images serve as the basis of the metrological analysis which showed that the standard approaches for the analysis of contact orientations, implemented in most commercial software, strongly suffer in accuracy and often introduce huge artefacts. New techniques to refine these measures are proposed and validated on the same images. Monotonic triaxial compression tests on two different sands are studied regarding the localisation of deformation in terms of the contact fabric. The complete fabric tensor is determined inside and outside of the developing shear band throughout the experiment. Its evolution is expressed by the anisotropy and related to the macroscopic response. The specimen appears to behave homogeneously in the different zones until the onset of the localisation at which the fabric diverges. Outside of the shear band it stays relatively constant whereas it seems directly related to the stress ratio inside the shear band. The anisotropy captures the characteristic evolution of the stress response, such as peak states and softening. A series of triaxial compression tests with load reversals has been conducted on specimens consisting of sand grains and glass beads. To capture the fabric response to the cycles, tomographies have been acquired before and after unloading and after reloading. As opposed to numerical simulations, no large changes of the fabric during the load cycles could be observed. Qualitatively, the fabric changes similar to the numerical simulations: the anisotropy decreases upon unloading and increases upon reloading. The incremental response to each reversal is compared to the numerical simulations and the evolution of the inter-granular strain tensor for similar conditions. The latter is determined by a simplified element test with the aim of possibly relating this phenomenological variable to a truly structural one. The comparison of the evolution of the fabric and the inter-granular strain, however, showed major differences, based on which such a relation is not possible. The fabric evolves at a slower rate than the state variable and continues to evolve even throughout monotonic loading situations. / Der Großteil der Stoffmodelle, die heutzutage zur Beschreibung des Verhaltens von granularen Materialien wie Sanden verwendet werden, sind Modelle im Kontinuum, die auf phänomenologischen Ansätzen basieren. Diese Stoffmodelle nutzen oft phänomenologische Zustandsvariablen (z.B. die intergranulare Dehnung in der Hypoplastizität), um Phänomene, die auf makroskopischer Ebene beobachtet werden können, wie z.B. ein abrupter Wechsel der Steifigkeit bei Lastumkehr, zu beschreiben. Der Großteil dieser Zustandsvariablen ist aus theoretischen Konzepten hervorgegangen, die bisher noch nicht auf experimentelle Grundlagen gestellt werden konnten. Die Mechanismen, die das makroskopische Verhalten und die Phänomene auf dieser Ebene kontrollieren, müssen auf der Kornskala gesucht werden, da die Interaktionen von individuellen Körnern die Schlüsselrolle spielen. Um die Struktur von Granulaten auf dieser Skala beschreiben zu können, kommt die Röntgen Computertomographie in dieser Arbeit zum Einsatz. Diese erlaubt es 3D Bilder von Proben während einer makroskopischen Belastung zu erstellen und somit Strukturänderungen zu verfolgen. Hierbei ist es wichtig, zu beachten, dass die räumliche Auflösung der Tomographien limitiert ist, da mechanisch repräsentative Proben untersucht werden sollen. Mit verschiedenen Bildbearbeitungstools können aus diesen Bildern Informationen zur Struktur der Proben gewonnen werden. Aufgrund der limitierten Auflösung und unzureichenden, bisher durchgeführten Studien war es notwendig, diese Tools auf ihre Genauigkeit zu untersuchen. Mit Hilfe von synthetischen Bildern und hochauflösenden Nano-Tomographien, die als Basis für diese Analyse dienten, konnte festgestellt werden, dass Standardverfahren, die auch in kommerziellen Programmen implementiert sind, eine unzureichende Genauigkeit aufweisen. Aus diesem Grund wurden fortgeschrittene Verfahren hinsichtlich ihrer Genauigkeit und Verwendbarkeit untersucht und Verfeinerungen der Standardverfahren vorgeschlagen. Es konnte gezeigt werden, dass diese Verbesserungen eine wesentlich höhere Genauigkeit hinsichtlich der zu bestimmenden Strukturgrößen aufweisen. Mit diesen optimierten Verfahren wurde die Lokalisierung von Verformungen in monotonen Triaxialversuchen an zwei verschiedenen Sanden untersucht. Dazu wurde die Struktur innerhalb und außerhalb eines sich entwickelnden Scherbandes bestimmt und über einen Strukturtensor dargestellt. Die Proben verhalten sich relativ homogen bis zum Anfang der Lokalisierung. Danach wird die Struktur innerhalb des Scherbandes zunehmend anisotroper, indem sich die Kontakte immer weiter in Richtung der größten Hauptspannung ausrichten. Außerhalb des Scherbandes verändert sie sich kaum. Die Anisotropie des Strukturtensors bildet die Entwicklung des Spannungsdeviators dabei sehr gut ab. Um die abrupte Änderung der Steifigkeit bei Lastumkehr zu untersuchen, wurden Experimente an Sand- und Glaskugelproben durchgeführt, bei denen die Lastrichtung zu unterschiedlichen Zuständen umgekehrt wurde. Dabei wurden Tomographien von der Probe inbesondere vor und nach der Entlastung sowie nach der Wiederbelastung erstellt. Im Gegensatz zu Untersuchungen mit der DEM, entwickelt sich die Struktur in diesen Experimenten nur sehr gering. Qualitativ sind die Änderungen aber ähnlich mit denen aus den numerischen Simulationen: die Anisotropie verringert sich bei Ent- und vergrößert sich bei Wiederbelastung. Die inkrementelle Änderung der Anisotropie bei Lastumkehr wurde mit den Ergebnissen aus den numerischen Simulationen sowie der Entwicklung der intergranularen Dehnung verglichen. Mit dem Ziel dieses phänomenologische Konzept auf experimentelle Grundlagen zu stellen, wurde die intergranulare Dehnung in einer Simulation bei ähnlichen Bedingungen ermittelt. Eine experimentelle Erklärung dieses Konzeptes ist zumindest mit der Kontaktstruktur nicht möglich, da sich beide Variablen unterschiedlich entwickeln. Die Struktur entwickelt sich langsamer als die Zustandsvariable und weit über die Lastumkehr hinaus. / La majorité des modèles constitutifs, utilisés aujourd’hui pour décrire le comportement de matériaux granulaires, sont des modèles de continuum basés sur des approches phénoménologiques. Afin de décrire certains des phénomènes qui se produisent à l’échelle macroscopique, par exemple: le changement brusque de rigidité à une inversion de charge, les modèles constitutifs utilisent des variables d’état phénoménologiques (par exemple: le concept de déformation intergranulaire pour l’hypoplasticité). Ces modèles manquent souvent d’une signification physique. Les mécanismes qui contrôlent le comportement macroscopique doivent être étudiés à l’échelle du grain, car les interactions des particules jouent un rôle essentiel. Pour accéder à cette échelle et décrire la structure des assemblages granulaires, la tomographie par rayons X est utilisée dans ces travaux de thèse. La résolution spatiale de telles tomographies est limitée car le spécimen doit avoir une taille mécaniquement représentative et en même temps doit être suffisamment petit pour identifier les grains individuels dans les images. Différentes techniques d’analyse d’images peuvent être utilisées pour extraire des informations sur la structure du matérial granulaire, mais elles manquent toutes d’une caractérisation métrologique approfondie.Donc, il était nécessaire d’étudier les différentes techniques et de déterminer leurs incertitudes. Les images artificielles ainsi que les images haute résolution servent de base à l’analyse métrologique, qui a montré que les approches standard pour l’analyse des orientations de contact, mises en œuvre dans la plupart des logiciels commerciaux, sont inexacts et entraînent souvent d’importants artefacts. De nouvelles techniques pour affiner ces mesures sont proposées et validées sur les mêmes images. Des essais de compression triaxiaux monotoniques sur deux sables différents sont étudiés en ce qui concerne la localisation de la déformation par rapport au structure de contact. Le tenseur de structure complet est déterminé à l’intérieur et à l’extérieur de la bande de cisaillement en développement tout au long de l’expérience. Son évolution est exprimée par l’anisotropie et liée à la réponse macroscopique. Le spécimen semble se comporter de manière homogène dans les différentes zones jusqu’au début de la localisation à laquelle le tissu diverge. En dehors de la bande de cisaillement, il reste relativement constant alors qu’il semble directement lié au taux de contrainte à l’intérieur de la bande de cisaillement. L’anisotropie capture l’évolution caractéristique de la réponse a la contrainte, telle que les états de pic et le ramollissement. Une série d’essais de compression triaxiale avec inversion de charge a été réalisée sur des échantillons constitués de grains de sable et de billes de verre. Pour capturer la réponse de la structure aux cycles de charge, des tomographies ont été acquises avant et après le déchargement et après le rechargement. Contrairement aux simulations numériques, aucun changement important du tissu au cours de ces cycles n’a pas pu être observé. Qualitativement, les changements de structure ressemblent à ceux des simulations numériques: l’anisotropie diminue au déchargement et augmente au rechargement. La réponse incrémentale à chaque inversion est comparée aux simulations numériques et à l’évolution du tenseur de déformation intergranulaire sous des conditions similaires. La déformation intergranulaire est déterminée par un test élémentaire simplifié dans le but de relier éventuellement cette variable phénoménologique à une variable véritablement structurelle. La comparaison de l’évolution du tissu et de la déformation intergranulaire a toutefois révélé des différences majeures, sur la base desquelles une telle relation n’est pas possible. La structure évolue à un taux plus lent que la variable d’état et continue d’évoluer même dans les situations de chargement monotone.

Malfunctions on loom machines are the main causes of faulty fabric production. An on-loom fabric inspection system is a real-time monitoring device that enables immediate defect detection for human intervention. This dissertation presented a solution for the on-loom fabric defect inspection, including the new hardware design—the configurable contact image sensor (CIS) module—for on-loom fabric scanning and the defect detection algorithms. The main contributions of this work include (1) creating a configurable CIS module adaptable to a loom width, which brings CIS unique features, such as sub-millimeter resolution, compact size, short working distance and low cost, to the fabric defect inspection system, (2) designing a two-level hardware architecture that can be efficiently deployed in a weaving factory with hundreds of looms, (3) developing a two-level inspecting scheme, with which the initial defect screening is performed on the Raspberry Pi and the intensive defect verification is processed on the cloud server, (4) introducing the novel pairwise-potential activation layer to a convolutional neural network that leads to high accuracies of defect segmentation on fabrics with fine and imbalanced structures, (5) achieving a real-time defect detection that allows a possible defect to be examined multiple times, and (6) implementing a new color segmentation technique suitable for processing multi-color fabric defects. The novel CIS-based on-loom scanning system offered real-time and high-resolution fabric images, which was able to deliver the information of single thread on a fabric. The algorithm evaluation on the fabric defect datasets showed a non-miss-detection rate on defect-free fabrics. The average precision of defect existed images reached above 90% at the pixel level. The detected defect pixels' integrity—the recall scored around 70%. Possible defect regions overestimated on ground truth images and the morphologies of fine defects similar to regular fabric pattern were the two major reasons that caused the imperfection in defect pixel locating. The experiments showed the defect areas on multi-color fabrics could be precisely located under the proposed color segmentation algorithm.