The introduction of Fibre Reinforced Polymers (FRP) to the civil engineering market in the late 1980s resulted in the emergence of a range of new tools for rehabilitating and strengthening concrete structures. Strengthening using FRPs is typically accomplished using non-prestressed externally bonded FRPs. The technical and economic benefits of such strengthening could be further increased by prestressing the FRPs, especially when dealing with concrete structures. Prestressing concrete structures suppresses the appearance and growth of cracks in the serviceability limit state. This in turn increases the structure’s stiffness and resistance to degradation. Prestressing also increases the structure’s yield load but does not change its failure load relative to that of an analogous non-prestressed structure, provided that all other parameters are kept constant. In 2004, a pilot study was carried out at the Luleå University of Technology (LTU) to investigate the scope for using unbonded Carbon Fibre Reinforced Polymer (CFRP) strengthening systems, particularly those involving prestressing. In the early stages of this project, a number of difficulties were encountered in anchoring the CFRP rods to concrete structures: the conical wedge anchorages that were used tended to either cause premature failure of the rods or allowed the rod to slip out of the anchorage. It was therefore decided to study the mechanisms at work within these anchorages in more detail. The goal of the project was to develop a small, practical, reliable, and userfriendly anchorage for use in unbonded external CFRP strengthening systems. On the basis of a thorough literature review, which is described in Paper 1, it was concluded that despite the difficulties encountered, the conical wedge anchorages used with steel reinforcing rods were the most promising starting point for the design of a new anchorage for use with CFRPs. Importantly, the conical wedge anchorage can be made small in size and easy to mount while retaining a high degree of versatility; this is not true of bonded, sleeve, and clamping anchorages. Analytical and numerical models were used to investigate the distribution of radial stress within these highly pressurized anchorages. Paper 2 describes an evaluation of the capability of three types of models - an analytical axisymmetric model based on the thick-walled-cylinder-theory and two Finite Element (FE) models, one axisymmetric and one three-dimensional - to predict the behaviour of a conical wedge anchorage. It was concluded that the axisymmetric models were incapable of modelling the stress distribution within the anchorage with sufficient accuracy, and so 3D FE models were used exclusively in subsequent studies. Paper 3 describes the development of a new anchorage for CFRP rods. The design process involved conducting pull-out studies on a series of prototypes, in conjunction with computational studies using a basic FE model, to identify and understand the prototypes’ failure modes. Between the computational data and experimental results, a good understanding of the factors affecting the interaction between the CFRP rod and the anchorage was obtained. The new anchorage design employs a one-piece wedge which effectively incorporates the three wedges and the inner sleeve from more conventional wedge anchorages into a single unit. This increases the reliability and user-friendliness of the anchorage because it eliminates the need to check the alignment of individual wedges. The new design has been patented; the published Swedish patent is included in the thesis as Paper 6. The newly-developed anchorage was then incorporated into a prestressing system and its performance was evaluated using a series of test beams. In parallel with the planning of these tests, a series of pull-out tests was conducted using the new anchorage. The strain measurements obtained in these experiments were compared to predictions made using a new, more advanced FE model, and used to refine the design of the new anchorage. Paper 4 describes this new FE model, the most important parameters affecting anchorage behaviour, and the final anchorage design. Paper 5 focuses on the possibilities provided by the new anchorage. Tests were performed using seven three meter long concrete beams prestressed with external unbonded CFRP tendons. One beam was unstrengthened; the other six were strengthened in different ways, with different prestressing forces, initial tendon depths, and with or without the use of a midspan deviator for the tendons. The results of these tests were compared to those obtained using otherwise identical beams prestressed with steel tendons and to the predictions of an analytical beam model developed for use with steel tendons. These tests showed that the prestressing works as intended and that the behaviour of beams prestressed with external unbonded CFRP tendons is fully comparable to that of beams prestressed with steel tendons. It was also found that the predictions of the analytical model were in good agreement with experimental observations, although there were some differences between the measured and predicted tendon stresses. The development of a functional anchorage represents a fulfilment of the objectives laid out at the start of this project, and represents an important step towards the practical use of prestressed unbonded external CFRP tendons in strengthening concrete structures. However, a number of outstanding questions remain to be addressed. Little is known about the safety of this kind of system, and the benefits of using CFRP tendons should be quantified. Furthermore, there are a number of potential technical issues that must be addressed. These include the risk of creep-rupture in the CFRP, the effects of thermal contraction and expansion on the anchorage, and the scalability of the anchorage as the tendon diameter is increased. Finally, the long-term behaviour of the anchorage and prestressing system should be investigated. / I och med introduktionen av fiberkompositer i byggbranschen under slutet av 80-talet har en rad nya verktyg för förstärkning och underhåll av betongkonstruktioner utvecklats. Förstärkning har oftast utförts med pålimmade kompositer utan förspänning. För att ytterligare öka verkningsgraden, både den tekniska och ekonomiska, kan förspänning vara en möjlighet. Särskilt för betongkonstruktioner. Förspänning av en betongkonstruktion medför att man i bruksgränstillståndet begränsar uppkomsten av sprickor och deras storlek. Det ger i sin tur en ökad styvhet hos konstruktionen. Därutöver höjs lasten för när det slakarmerade stålet flyter. I jämförelse med ospända konstruktioner är dock brottlasten densamma, så länge övriga parametrar behålls. Under 2004 genomfördes en pilotstudie vid Luleå tekniska universitet (LTU) för att undersöka framtida möjligheter och utmaningar med förspända, icke vidhäftande kolfiberkompositkablar. I det läget upptäcktes svårigheter att förankra kompositkabeln mot betongen. De koniska killås som användes orsakade antingen brott på kabeln redan vid låga belastningar eller glidning hos kabeln, som omöjliggjorde fullgod kraftöverföring. Ett beslut togs då att tills vidare fokusera på förankringen och genomföra en mer ingående studie kring denna. Som mål sattes upp att arbetet skulle resultera i en liten, tillförlitlig och användarvänlig förankring. Den skulle sen i en förlängning kunna användas för att slutföra pilotstudien och därefter i större tillämpningar. Trots de förhållandevis nedslående resultaten från pilotförsöken visade den grundliga litteraturstudien som presenteras i Artikel 1 att koniska killås trots allt verkar vara den mest lovande typen av förankring för kolfiberkablar. Den bör därför användas som utgångspunkt för fortsatt utveckling. I motsats till vidhäftande, hyls och klämmande förankringar kan killåset göras litet, lätt att montera och också användas i många praktiska tillämpningar. För att undersöka hur de höga radiella tryckspänningarna i ett sådant killås fördelas är olika former av beräkningsmodeller nödvändiga verktyg. I Artikel 2 jämförs tre olika modeller med avseende på hur väl de kan beskriva komplexiteten hos ett koniskt killås. Det är dels en analytisk axisymmetrisk modell, som också härleds i artikeln, dels en axisymmetrisk Finita Element (FE) modell och dels en 3D FE modell. Undersökningen visade att ingen av de axisymmetriska modellerna har kapacitet nog att tillförlitligt modellera killåset. I fortsatta undersökningar har därför endast 3D FE använts. Resultaten från en enkel FE modell ligger också, tillsammans med tidiga laboratorieförsök, som grund för Artikel 3. Däri beskrivs hur ett nytt killås via prototyper och nya lösningar utvecklats, och hur arbetet för att få fram det nya låset också gett en bättre förståelse för interaktionen mellan kolfiberkompositkabel och lås. Som avslutning presenteras en innovativ design där de tre kilarna och den inre hylsan sammanfogats till en enhet. Med den nyutvecklade designen blir förankringen såväl mer tillförlitlig som användarvänlig. Alla kilar har då redan från början rätt position i förhållande till varandra. Den utvecklade förankringslösningen har också lett fram till ett beviljat svenskt patent, bifogat i avhandlingen som Artikel 6. Efter utvecklingen av den nya förankringen var nästa steg i de uppsatta målen implementering av densamma i ett förspänningssystem och nya balkförsök i konstruktionslabbet. Parallellt med planeringen för balkförsöken pågick ett arbete med att ytterligare förbättra låsdesignen. Bland annat användes en mer detaljerad FE modell som sedan jämfördes med mätningar från en ny serie med dragprov. Den nya FE modellen tillsammans med en utvärdering av viktiga parametrar och den slutliga förankringsdesignen presenteras i Artikel 4. Artikel 5 sammanfattar och avslutar forskningsstudien med en testserie om sju stycken, tre meter långa, betongbalkar förspända med utanpåliggande kolfiberkompositstavar. En av balkarna provades utan förstärkning. Förstärkningen hos de övriga varierades med avseende på förspänningsgrad, förspänningens effektiva höjd och användandet av deviator vid balkmitt. Resultaten har jämförts mellan de provade balkarna, med identiska balkar förspända med stålkablar samt med en analytisk modell utvecklad för förspänning med stålkablar. Från resultaten kan utläsas att förspänningen fungerar bra och att beteendet hos balkarna förspända med utanpåliggande kolfiberkablar är fullt jämförbart med det hos balkarna förspända med stålkablar. Likaså visar jämförelsen med de modellerade beteendena på god överensstämmelse, även om vissa skillnader finns mellan uppmätta och modellerade spänningar i kolfiberkabeln. Med målen för forskningen uppfyllda och en ny fungerande förankring framtagen så har vägen till praktiska tillämpningar kortats betydligt, ändå finns några frågetecken kvar att räta ut. Ett är säkerheten hos den här typen av system och nyttan av att använda kolfiberkomposit istället för stål. Innan systemet används i praktiken bör därför följande frågeställningar belysas: Risk för krypbrott i kolfiberarmeringen, inverkan av temperaturförändringar (och temperaturrörelser) i förankringen samt eventuella storlekseffekter vid förankring av kablar med större diametrar. De här frågorna tillsammans med långtidsförsök på förankringen och förspänningssystemet bör ses som viktiga framtida forskningsfrågor. / Godkänd; 2011; 20110128 (ysko); DISPUTATION Ämnesområde: Konstruktionsteknik/Structural Engineering Opponent: PhD Chris Burgoyne, Dep of Engineering, University of Cambridge, UK Ordförande: Professor Björn Täljsten, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Tid: Fredag den 18 februari 2011, kl 10.00 Plats: F1031, Luleå tekniska universitet

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Approved for public release; distribution in unlimited. / This thesis represents a cross Systems Command (NAVSEA/NAVAIR) developed product. The product - the Sunset Supply Base (SSB) system - provides a complete system for addressing the risks and supportability issues involved with Commercial Off the Shelf (COTS) products in Navy combat and support systems. The SSB system was implemented on three Navy combat weapon systems at various phases of the product development life cycle. The main body provides to the Program Management Offices (PMO) and other decision makers, a high level summary of performance expectations. Appendix A - The Sunset Supply Base Architecture - identifies at a high level of abstraction a collaborative architecture providing a roadmap for design and development of the SSB system. Appendix B - The Systems Engineering Development and Implementation (SEDI) plan - is a prescriptive or "How to" manual describing activities that have been used to successfully implement the SSB system. Appendix C - Business Case Analysis (BCA) - presents the data collected as a result of SEDI plan implementation then addresses the business/programmatic attributes showing the viability and value proposition possible through the SSB system. Appendix D - The Marketing Plan for the SSB system - defines methods and practices necessary to establish the SSB system as the alternative of choice. / Chemical Engineer, United States Navy / Systems Engineer, United States Navy

<p>This thesis is structured in six chapters. Chapter I contains an introduction and includes purpose, theory, method, and concepts. The main purpose, as depicted by the title, is to examine the roots of Swedish ideology concerning what today is generally named design, as embodied in the concept of more beautiful or better things for everyday life (in Swedish: ”vackrare vardagsvara”).</p><p>Chapter II contains a background and includes philosophical ideas and aesthetic movements in Europe which have influenced the Swedish Society of Arts and Crafts (in Swedish ”Svenska Slöjdföreningen”, abbreviated SSF) which was later renamed the Swedish Society of Crafts and Design (in Swedish: ”Föreningen Svensk Form”). It considers these activities: the Arts and Crafts movement in England, the Swedish national romantic movement, Deutscher Werkbund in Germany, and Swedish moulders of public opinion and new ideas, like Ellen Key, Carl Larsson and Gregor Paulsson.</p><p>Chapter III is an ideological biography of Gregor Paulsson. The chapter deals with biographical data and ideological development, and the social aesthetical texts which were important in his activity in the National Museum and as director of The Swedish Society of Arts and Crafts. Gregor Paulsson is considered mainly in his role as social aesthetical propagandist and museologist.</p><p>Chapter IV concerns the early history and activities of the Swedish Society of Arts and Crafts seen as an introduction to the Baltic Exhibition 1914, and the subsequent schism which eventually led to its reorganization and a new ideological orientation. Its activities were directed towards increased cooperation between artists and industry, and a special department was established as an employment office for companies and designers under the management of the textile artist Elsa Gullberg. This chapter also includes a brief portrait of key persons in the Society.</p><p>Chapter V is a study in several sections of the articles for everyday use seen in industrial practice, with Gustavsberg’s china factory and Orrefors’ glassworks as two separate historical studies. The 1917 Home Exhibition is surveyed as an example of the educational ambitions in the development of people’s taste. The focus of the chapter, however, is the international industrial art exhibition in Paris 1925, Exposition International des Arts Décoratifs et Industriels Modernes, and the debate about it in the Swedish and French press.</p><p>Chapter VI consists of a concluding discussion with a final epilogue. It contains suggested questions for future research including relations between design and ethics.</p>

This thesis is structured in six chapters. Chapter I contains an introduction and includes purpose, theory, method, and concepts. The main purpose, as depicted by the title, is to examine the roots of Swedish ideology concerning what today is generally named design, as embodied in the concept of more beautiful or better things for everyday life (in Swedish: ”vackrare vardagsvara”). Chapter II contains a background and includes philosophical ideas and aesthetic movements in Europe which have influenced the Swedish Society of Arts and Crafts (in Swedish ”Svenska Slöjdföreningen”, abbreviated SSF) which was later renamed the Swedish Society of Crafts and Design (in Swedish: ”Föreningen Svensk Form”). It considers these activities: the Arts and Crafts movement in England, the Swedish national romantic movement, Deutscher Werkbund in Germany, and Swedish moulders of public opinion and new ideas, like Ellen Key, Carl Larsson and Gregor Paulsson. Chapter III is an ideological biography of Gregor Paulsson. The chapter deals with biographical data and ideological development, and the social aesthetical texts which were important in his activity in the National Museum and as director of The Swedish Society of Arts and Crafts. Gregor Paulsson is considered mainly in his role as social aesthetical propagandist and museologist. Chapter IV concerns the early history and activities of the Swedish Society of Arts and Crafts seen as an introduction to the Baltic Exhibition 1914, and the subsequent schism which eventually led to its reorganization and a new ideological orientation. Its activities were directed towards increased cooperation between artists and industry, and a special department was established as an employment office for companies and designers under the management of the textile artist Elsa Gullberg. This chapter also includes a brief portrait of key persons in the Society. Chapter V is a study in several sections of the articles for everyday use seen in industrial practice, with Gustavsberg’s china factory and Orrefors’ glassworks as two separate historical studies. The 1917 Home Exhibition is surveyed as an example of the educational ambitions in the development of people’s taste. The focus of the chapter, however, is the international industrial art exhibition in Paris 1925, Exposition International des Arts Décoratifs et Industriels Modernes, and the debate about it in the Swedish and French press. Chapter VI consists of a concluding discussion with a final epilogue. It contains suggested questions for future research including relations between design and ethics.