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O reparo em dutos defeituosos é previsto por normas e literatura, porém existe grande espaço para definição dos parâmetros ideais para aplicação prática e avaliação do desempenho destes reparos em fadiga. O presente trabalho tem por objetivo a definição dos parâmetros ideais para aplicação de reparos eficientes do tipo dupla calha sem solda circunferencial e com carregamento externo em escala real em dutos com defeitos de mossa com cava. O reparo é baseado na instalação de duas calhas concêntricas ao duto a ser reparado, preenchendo-se o defeito com resina e aplicando carga de compressão através de atuadores hidráulicos com correntes a fim de induzir tensões compressivas na região do defeito e, por fim, as calhas são unidas longitudinalmente pelo processo de soldagem. Para este trabalho, foi realizada uma modelagem numérica utilizando o método de elementos finitos de modo a simular a reprodução do defeito, ensaios de fadiga sem reparo, parâmetros para aplicação do reparo, ensaios de fadiga com reparo e, por fim, ensaio hidrostático. O procedimento proposto foi a reprodução do defeito, primeiramente o duto foi deformado com uma esfera metálica, de modo a formar uma mossa de profundidade igual a 6 % do diâmetro externo e, em seguida, a cava foi usinada com a utilização de um disco abrasivo. Após a produção do defeito, três amostras foram ensaiadas em fadiga, de modo a produzir uma amostra de referência sem reparo a ser comparada com os corpos de prova com reparo. O reparo dupla calha foi aplicado em duas amostras com defeito, sendo essas então submetidas a ensaios de fadiga. Esses ensaios indicaram que ambas as amostras resistiram a um número de ciclos correspondentes a 100 anos de vida em serviço. Por fim, as amostras reparadas após o ensaio de fadiga foram submetidas a ensaios hidrostáticos até a ruptura, a fim de avaliar a vida remanescente. Ambos os dutos romperam fora da região reparada, com uma pressão 2,1 %, menor que a pressão calculada analiticamente. Como principal resultado, foram obtidos parâmetros ideais para aplicação do reparo dupla calha em dutos com defeito tipo mossa com cava. Os resultados experimentais mostram convergência em relação aos dados do modelo numérico, provando que a modelagem por elementos finitos pode ser uma ferramenta útil no desenvolvimento deste tipo de trabalho. / Defective duct repairs are envisaged by norms and by the literature, yet there is enough space left to define ideal parameters for practical application and performance evaluation of these fatigue repairs. This work’s objective is to define the ideal parameters for the application of efficient repairs in double spouts without circumferential welding and real scale external loading in ducts with dent and gouge defects. The repair is based on the installation of two concentric spouts in the duct, filling the defect with resin and applying compression loading through hydraulic actuators with currents to induce compressive stresses in the defective area. Afterwards, the spouts are united lengthwise through the process of welding. To develop this work, we conducted a numerical modelling by using the finite element method to simulate the reproduction of the defect, as well as fatigue tests with no repairs, parameters for the application of repairs, fatigue tests with repairs, and finally a hydrostatic test. The proposed procedure was the reproduction of the defect. At first the duct was deformed with a metallic sphere, to form a dent whose depth was equal to 6 % of the external diameter and, subsequently, the gouge was machined with the help of an abrasive disk. Following the production of a defect, three samples were tested in fatigue to produce a reference sample without repair which would be compared to the samples with repairs. The double spout repair was applied in two samples with defects, which were then subjected to fatigue tests. These tests showed that both samples resisted to a number of cycles corresponding to a 100-year use lifespan. At last, the samples repaired after fatigue tests were subjected to hydrostatic tests until rupture, in order to evaluate their remaining lifespan. Both ducts ruptured outside of the repaired region, with a stress rate of 2.1 %, lower than the stress calculated analytically. The main result of this study was obtaining ideal parameters for the application of double spout repair in ducts with dents and gouge defects. The experimental results show convergence in relation to the numerical model data, proving that finite element modelling can be a useful tool when conducting this kind of work.

O reparo em dutos defeituosos é previsto por normas e literatura, porém existe grande espaço para definição dos parâmetros ideais para aplicação prática e avaliação do desempenho destes reparos em fadiga. O presente trabalho tem por objetivo a definição dos parâmetros ideais para aplicação de reparos eficientes do tipo dupla calha sem solda circunferencial e com carregamento externo em escala real em dutos com defeitos de mossa com cava. O reparo é baseado na instalação de duas calhas concêntricas ao duto a ser reparado, preenchendo-se o defeito com resina e aplicando carga de compressão através de atuadores hidráulicos com correntes a fim de induzir tensões compressivas na região do defeito e, por fim, as calhas são unidas longitudinalmente pelo processo de soldagem. Para este trabalho, foi realizada uma modelagem numérica utilizando o método de elementos finitos de modo a simular a reprodução do defeito, ensaios de fadiga sem reparo, parâmetros para aplicação do reparo, ensaios de fadiga com reparo e, por fim, ensaio hidrostático. O procedimento proposto foi a reprodução do defeito, primeiramente o duto foi deformado com uma esfera metálica, de modo a formar uma mossa de profundidade igual a 6 % do diâmetro externo e, em seguida, a cava foi usinada com a utilização de um disco abrasivo. Após a produção do defeito, três amostras foram ensaiadas em fadiga, de modo a produzir uma amostra de referência sem reparo a ser comparada com os corpos de prova com reparo. O reparo dupla calha foi aplicado em duas amostras com defeito, sendo essas então submetidas a ensaios de fadiga. Esses ensaios indicaram que ambas as amostras resistiram a um número de ciclos correspondentes a 100 anos de vida em serviço. Por fim, as amostras reparadas após o ensaio de fadiga foram submetidas a ensaios hidrostáticos até a ruptura, a fim de avaliar a vida remanescente. Ambos os dutos romperam fora da região reparada, com uma pressão 2,1 %, menor que a pressão calculada analiticamente. Como principal resultado, foram obtidos parâmetros ideais para aplicação do reparo dupla calha em dutos com defeito tipo mossa com cava. Os resultados experimentais mostram convergência em relação aos dados do modelo numérico, provando que a modelagem por elementos finitos pode ser uma ferramenta útil no desenvolvimento deste tipo de trabalho. / Defective duct repairs are envisaged by norms and by the literature, yet there is enough space left to define ideal parameters for practical application and performance evaluation of these fatigue repairs. This work’s objective is to define the ideal parameters for the application of efficient repairs in double spouts without circumferential welding and real scale external loading in ducts with dent and gouge defects. The repair is based on the installation of two concentric spouts in the duct, filling the defect with resin and applying compression loading through hydraulic actuators with currents to induce compressive stresses in the defective area. Afterwards, the spouts are united lengthwise through the process of welding. To develop this work, we conducted a numerical modelling by using the finite element method to simulate the reproduction of the defect, as well as fatigue tests with no repairs, parameters for the application of repairs, fatigue tests with repairs, and finally a hydrostatic test. The proposed procedure was the reproduction of the defect. At first the duct was deformed with a metallic sphere, to form a dent whose depth was equal to 6 % of the external diameter and, subsequently, the gouge was machined with the help of an abrasive disk. Following the production of a defect, three samples were tested in fatigue to produce a reference sample without repair which would be compared to the samples with repairs. The double spout repair was applied in two samples with defects, which were then subjected to fatigue tests. These tests showed that both samples resisted to a number of cycles corresponding to a 100-year use lifespan. At last, the samples repaired after fatigue tests were subjected to hydrostatic tests until rupture, in order to evaluate their remaining lifespan. Both ducts ruptured outside of the repaired region, with a stress rate of 2.1 %, lower than the stress calculated analytically. The main result of this study was obtaining ideal parameters for the application of double spout repair in ducts with dents and gouge defects. The experimental results show convergence in relation to the numerical model data, proving that finite element modelling can be a useful tool when conducting this kind of work.

O reparo em dutos defeituosos é previsto por normas e literatura, porém existe grande espaço para definição dos parâmetros ideais para aplicação prática e avaliação do desempenho destes reparos em fadiga. O presente trabalho tem por objetivo a definição dos parâmetros ideais para aplicação de reparos eficientes do tipo dupla calha sem solda circunferencial e com carregamento externo em escala real em dutos com defeitos de mossa com cava. O reparo é baseado na instalação de duas calhas concêntricas ao duto a ser reparado, preenchendo-se o defeito com resina e aplicando carga de compressão através de atuadores hidráulicos com correntes a fim de induzir tensões compressivas na região do defeito e, por fim, as calhas são unidas longitudinalmente pelo processo de soldagem. Para este trabalho, foi realizada uma modelagem numérica utilizando o método de elementos finitos de modo a simular a reprodução do defeito, ensaios de fadiga sem reparo, parâmetros para aplicação do reparo, ensaios de fadiga com reparo e, por fim, ensaio hidrostático. O procedimento proposto foi a reprodução do defeito, primeiramente o duto foi deformado com uma esfera metálica, de modo a formar uma mossa de profundidade igual a 6 % do diâmetro externo e, em seguida, a cava foi usinada com a utilização de um disco abrasivo. Após a produção do defeito, três amostras foram ensaiadas em fadiga, de modo a produzir uma amostra de referência sem reparo a ser comparada com os corpos de prova com reparo. O reparo dupla calha foi aplicado em duas amostras com defeito, sendo essas então submetidas a ensaios de fadiga. Esses ensaios indicaram que ambas as amostras resistiram a um número de ciclos correspondentes a 100 anos de vida em serviço. Por fim, as amostras reparadas após o ensaio de fadiga foram submetidas a ensaios hidrostáticos até a ruptura, a fim de avaliar a vida remanescente. Ambos os dutos romperam fora da região reparada, com uma pressão 2,1 %, menor que a pressão calculada analiticamente. Como principal resultado, foram obtidos parâmetros ideais para aplicação do reparo dupla calha em dutos com defeito tipo mossa com cava. Os resultados experimentais mostram convergência em relação aos dados do modelo numérico, provando que a modelagem por elementos finitos pode ser uma ferramenta útil no desenvolvimento deste tipo de trabalho. / Defective duct repairs are envisaged by norms and by the literature, yet there is enough space left to define ideal parameters for practical application and performance evaluation of these fatigue repairs. This work’s objective is to define the ideal parameters for the application of efficient repairs in double spouts without circumferential welding and real scale external loading in ducts with dent and gouge defects. The repair is based on the installation of two concentric spouts in the duct, filling the defect with resin and applying compression loading through hydraulic actuators with currents to induce compressive stresses in the defective area. Afterwards, the spouts are united lengthwise through the process of welding. To develop this work, we conducted a numerical modelling by using the finite element method to simulate the reproduction of the defect, as well as fatigue tests with no repairs, parameters for the application of repairs, fatigue tests with repairs, and finally a hydrostatic test. The proposed procedure was the reproduction of the defect. At first the duct was deformed with a metallic sphere, to form a dent whose depth was equal to 6 % of the external diameter and, subsequently, the gouge was machined with the help of an abrasive disk. Following the production of a defect, three samples were tested in fatigue to produce a reference sample without repair which would be compared to the samples with repairs. The double spout repair was applied in two samples with defects, which were then subjected to fatigue tests. These tests showed that both samples resisted to a number of cycles corresponding to a 100-year use lifespan. At last, the samples repaired after fatigue tests were subjected to hydrostatic tests until rupture, in order to evaluate their remaining lifespan. Both ducts ruptured outside of the repaired region, with a stress rate of 2.1 %, lower than the stress calculated analytically. The main result of this study was obtaining ideal parameters for the application of double spout repair in ducts with dents and gouge defects. The experimental results show convergence in relation to the numerical model data, proving that finite element modelling can be a useful tool when conducting this kind of work.

Unidirectional basalt fiber rods consolidated with an aramid sleeve were measured for compression strength after impact at various energy levels and compared to undamaged control specimens. These structural elements represent local members of open three-dimensional composite lattice structures (e.g., based on isogrid or IsoTruss® technologies) that are continuously fabricated using advanced three-dimensional braiding techniques. The unidirectional core specimens, nominally 8 mm (5/16") and 11 mm (7/16") in diameter, were manufactured using bi-directional braided sleeves or unidirectional spiral sleeves with full or partial (approximately half) coverage of the core fibers. The 51 mm (2") specimens were shorter than the critical buckling length, ensuring the formation of kink bands, typical of strength-controlled compression failure of unidirectional composites. The test results indicate an approximate decrease in the average undamaged compression strength of approximately 1/3 and 2/3 when impacted with 5 J (3.7 ft-lbs) and 10 J (7.4 ft-lbs) for the 8 mm (5/16") diameter specimens and 10 J (7.4 ft-lbs.) and 20 J (14.8 ft-lbs.) for the 11 mm (7/16") diameter specimens, respectively. The aramid sleeves improved the damage tolerance of the composite members, with the amount of coverage having the greatest effect; full coverage exhibiting up to 45% greater strength than partial coverage. Braided sleeves improved compression strength after impact by up to 23% over spiral sleeves, but generally had little effect on damage tolerance. Larger diameter specimens tend to be more resistant to damage than those specimens of a smaller diameter. The compressive material properties for undamaged basalt composites are also presented with the average compressive strength being 800 MPa (116 ksi).

Syfte: Att undersöka vilka dokumenterade, akuta effekter knee wraps och knee sleeves har på prestationen vid muskelstärkande träning hos personer med friska knän. Metod: Systematisk litteraturöversikt. Artiklar har sökts i databaserna Pubmed, Discover, Medline, Scopus, Web of Science. Inklusionskriterier: deltagare med friska knän, användning av knee wraps eller knee sleeves vid träning, artiklar tillgängliga i fulltext samt peer-reviewed. Exklusionskriterier: Artiklar som inte är skrivna på engelska eller svenska, böcker samt artiklar publicerade innan 2003.  Resultat: 13 artiklar inkluderades i studien med totalt 202 deltagare. Testerna som utfördes i de 13 studierna var benböj, benpress, knäflexion eller knä extension med knee sleeves eller knee wraps. Resultatet påvisar att knee sleeves inte påverkade prestationen (explosivitet, RPE, styrka, teknik, uthållighet, proprioception), men bidrar till komfort och stabilitet till knät. Knee wraps ökar prestationen genom den elastiska energin som samlas i lindan. Detta bidrar till ökad explosivitet och tillåter användaren att lyfta mer vikt. Däremot verkar den elastiska energin kompensera för den egna styrkan. Resultaten av litteraturöversikten indikerar även på att knee wraps verkar minska muskel-aktiveringen i nedre delen av kroppen.  Slutsats: Knee sleeves bör inte användas för att förbättra prestationen vid muskelstärkande träning, däremot kan stödet användas av dem som önskar ökad komfort och stabilitet till knät. Knee wraps verkar ha goda effekter på prestationsförmågan och kan med fördel användas i samband med tävling för att lyfta mer vikt. Däremot bör lindan inte användas av den som strävar efter ökad muskelstorlek och styrka då knee wraps kompenserar för den egna styrkan och verkar minska muskel-aktiveringen i underkroppen.

Investigated in this research was the effect of different shoulder positions on different sleeve/bodice structures. Since a sleeve/bodice may have numerous variations and design details incorporated into the structure, this research concentrated on the set-in sleeve, kimono sleeve, raglan sleeve, and kimono sleeve with gusset. The variables used to determine the reaction of the different structures to different shoulder positions were garment slippage away from the wrist, the waist, the center back/waistline positions, and the angle formed by the center back/waistline intersection. A Factorial ANOVA was used to test for significant differences between the sleeve/bodice structures and shoulder positions. A Tukey's pairwise comparison was used to determined the difference between the slippage at each shoulder position and each sleeve/bodice structure compared with each of the others. Regression equations were fit as linear, quadratic and their interactions with each sleeve/bodice structure. Based on the theoretical framework, the amount and location of the slippage found in the statistical analyses was not necessarily those predicted. From the analyses, it was determined that when comparing the slippage at the wrist, waist, center back/waistline location and the center/back angle as a whole, general trends which occurred in the data were that the set-in sleeve consistently exhibited the greatest amount of slippage and the kimono sleeve exhibited the least. From the plots of the regression coefficients, the amount of slippage illustrated for the raglan sleeve was of similar slope to that of the set-in sleeve, whereas the kimono sleeve with gusset was more closely related to the slippage of the kimono sleeve. The results of this study provide information that other clothing designers may find useful when developing sleeve/bodice structures based on specific shoulder positions. From known shoulder positions, a designer may determine which sleeve/bodice structure would exhibit the least or most garment slippage, or be able to predict the amount of garment slippage for a specific structure. / Ph. D.

Unidirectional carbon fiber and fiberglass epoxy composite elements consolidated with aramid sleeves were radially impacted at 5 J (3.7 ft-lbs) and 10 J (7.4 ft-lbs), tested under compression, and compared to undamaged control specimens. These structural elements represent local members of open three-dimensional composite lattice structures (e.g., based on isogrid or IsoTruss® technologies). Advanced three-dimensional braiding techniques were used to continuously fabricate these specimens. The unidirectional core specimens, 8 mm (5/16 in) in diameter, were manufactured with various sleeve patterns. Bi-directional braided sleeves and unidirectional spiral sleeves ranged from a nominal full to half coverage. These specimens were tested for compression strength after impact. This research used an unsupported length of 50.8 mm (2.0 in) specimens to ensure a strength-controlled compression failure. Compression strength of undamaged unidirectional carbon fiber and fiberglass epoxy composites is virtually unaffected by sleeve type and sleeve coverage. Fiberglass/epoxy configurations exhibited approximately 1/2 and 2/3 reduction in compression strength relative to undamaged configurations after impact with 5 J (3.7 ft-lbs) and 10 J (7.4 ft-lbs), respectively. Increasing aramid sleeve coverage and/or increasing the interweaving of an aramid sleeve (i.e., braid vs. spiral) increases the damage tolerance of fiberglass/epoxy composite elements. Damaged carbon/epoxy composites exhibited an approximate decrease in strength of 70% and 75% after 5 J and 10 J of impact, respectively, relative to undamaged configurations. The results verify that an aramid sleeve, regardless of type (braid or spiral), facilitates consolidation of the carbon fiber and fiberglass epoxy core. Not surprisingly, full coverage configurations exhibit greater compression strength after impact than half coverage configurations.