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A palatalização das oclusivas dentais /t/ e /d/ nas comunidades bilingües de Taquara e Panambi-RS : análise quantitativaPaula, Alice Telles de January 2006 (has links)
Esta é uma análise da variação das oclusivas dentais [t, d], seguidas da vogal alta /i/ nas comunidades lingüísticas de Taquara e Panambi (RS), a partir das amostras de vinte e quatro informantes do Projeto VARSUL (Variação Lingüística na Região Sul). As amostras examinadas foram coletadas em épocas distintas, o que dá condições para analisar o comportamento variável em dois momentos de tempo. A análise individual de cada grupo geográfico tem por objetivo comparar a aplicação da regra variável em uma perspectiva de mudança lingüística em tempo real, segundo os moldes labovianos (1994). A análise conjunta tem por objetivo analisar o comportamento variável em estudo, verificando-se os possíveis condicionadores lingüísticos e extralingüísticos intervenientes, tendo por base um número mais significativo de dados ao juntar as amostras das duas comunidades lingüísticas. Os resultados estatísticos mostraram que em Taquara e em Panambi a aplicação da regra variável é semelhante e que se encontra em estado de aquisição. / This is an analysis of the variation of the dental stops [t, d], followed of the high vowel /i/ in the linguistic communities of Taquara and Panambi (RS), from the samples of twenty and four informers of Project VARSUL (Linguistic Variation in the South Region). The examined samples were collected at distinct times, what it gives conditions to analyze the changeable behavior at two moments of time. The individual analysis of each geographic group has for objective to compare the application of the changeable rule in a perspective of linguistic change in real time, according to labovianos molds (1994). The joint analysis has for objective to analyze the changeable behavior in study, verifying itself the possible intervening linguistic and extralinguistic conditioners, having for base a more significant number of data when joining the samples of the two linguistic communities. The statistical results had shown that in Taquara and Panambi the application of the changeable rule is similar and that meets in acquisition state.
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A clustering-based approach for discovering interesting places in trajectories / Uma abordagem baseada em clusterização para a descoberta de lugares de interesse em trajetóriasPalma, Andrey Luis Tietbohl January 2008 (has links)
Por causa da grande quantidade de dados de trajetórias producidos por dispositivos móveis, existe um aumento crescente das necessidades de mecanismos para extrair conhecimento a partir desses dados. A maioria dos trabalhos existentes focam nas propriedades geometricas das trajetorias, mas recentemente surgiu o conceito de trajetórias semânticas, nas quais a informação da geografia por baixo da trajetória é integrada aos pontos da trajetória. Nesse novo conceito, trajetórias são observadas como um conjunto de stops e moves, onde stops são as partes mais importantes da trajetória. Os stops e moves são computados pela intersecção das trajetórias com o conjunto de objetos geográficos dados pelo usuário. Nessa dissertação será apresentada uma solução alternativa a descoberta de stops, com a capacidade de achar lugares de interesse que não são esperados pelo usuário. A solução proposta é um método de clusterização espaço-temporal, baseado na velocidade, para ser aplicado em uma trajetória. Foram comparadas duas abordagens diferentes com experimentos baseados em dados reais e mostrado que a computação de stops usando o conceito de velocidade pode ser interessante para várias applicações. / Because of the large amount of trajectory data produced by mobile devices, there is an increasing need for mechanisms to extract knowledge from this data. Most existing works have focused on the geometric properties of trajectories, but recently emerged the concepts of semantic trajectories, in which the background geographic information is integrated to trajectory sample points. In this new concept, trajectories are observed as a set of stops and moves, where stops are the most important parts of the trajectory. Stops and moves have been computed by testing the intersection of trajectories with a set of geographic objects given by the user. In this dissertation we present an alternative solution with the capability of finding interesting places that are not expected by the user. The proposed solution is a spatio-temporal clustering method, based on speed, to work with single trajectories. We compare the two different approaches with experiments on real data and show that the computation of stops using the concept of speed can be interesting for several applications.
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Optimization Models for Selecting Bus Stops for Accessibility Improvements for People with DisabilitiesWu, Wanyang 26 March 2009 (has links)
Bus stops are key links in the journeys of transit patrons with disabilities. Inaccessible bus stops prevent people with disabilities from using fixed-route bus services, thus limiting their mobility. The Americans with Disabilities Act (ADA) of 1990 prescribes the minimum requirements for bus stop accessibility by riders with disabilities. Due to limited budgets, transit agencies can only select a limited number of bus stop locations for ADA improvements annually. These locations should preferably be selected such that they maximize the overall benefits to patrons with disabilities. In addition, transit agencies may also choose to implement the universal design paradigm, which involves higher design standards than current ADA requirements and can provide amenities that are useful for all riders, like shelters and lighting. Many factors can affect the decision to improve a bus stop, including rider-based aspects like the number of riders with disabilities, total ridership, customer complaints, accidents, deployment costs, as well as locational aspects like the location of employment centers, schools, shopping areas, and so on. These interlacing factors make it difficult to identify optimum improvement locations without the aid of an optimization model. This dissertation proposes two integer programming models to help identify a priority list of bus stops for accessibility improvements. The first is a binary integer programming model designed to identify bus stops that need improvements to meet the minimum ADA requirements. The second involves a multi-objective nonlinear mixed integer programming model that attempts to achieve an optimal compromise among the two accessibility design standards. Geographic Information System (GIS) techniques were used extensively to both prepare the model input and examine the model output. An analytic hierarchy process (AHP) was applied to combine all of the factors affecting the benefits to patrons with disabilities. An extensive sensitivity analysis was performed to assess the reasonableness of the model outputs in response to changes in model constraints. Based on a case study using data from Broward County Transit (BCT) in Florida, the models were found to produce a list of bus stops that upon close examination were determined to be highly logical. Compared to traditional approaches using staff experience, requests from elected officials, customer complaints, etc., these optimization models offer a more objective and efficient platform on which to make bus stop improvement suggestions.
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The Acquisition of Fine Phonetic Detail in a Foreign Language: Perception and Production of Stops in L2 English and L1 PortugueseOsborne, Denise Maria, Osborne, Denise Maria January 2016 (has links)
This study investigated the perception and production of L2 English and L1 Portuguese stops in initial position by analyzing the acquisition of voice onset time (VOT) categories. 36 Brazilian Portuguese (BP) learners of English and 36 monolingual BP speakers, all of them living in Brazil, participated in this study. There were two language sessions, English and Portuguese (monolinguals took part in the Portuguese session only). In each language session, participants took part in a production and a perception task in the respective language (the tasks were mirror-images of each other). To elicit the production data, participants took part in a delayed repetition task. To elicit the perception data, participants took part in a two-alternative forced-choice identification test. The analysis of the data showed that improvement in L2 may entail improvement in L2 perception of stops. On the other hand, the lack of effects of proficiency in L2 production of stops may suggest occurrence of learning stabilization of L2 VOT categories. L1 phonetic drift was observed in the production of the Portuguese /b/, /k/, and /g/ (but not for /p/). However, no effects of L2 learning on L1 was observed for the perception of Portuguese /b/-/p/. L2 learners who had learned English in their L1 country and in formal settings demonstrated that they were able to form new phonetic categories for the production of /p/, /b/, and /g/. The higher-proficiency group (but not the lower-proficiency group) demonstrated that they developed language-specific phonetic strategies for /p/-/b/ since they were able to process the same set of sounds on a continuum from /b/ to /p/ as either L1 or L2 stops as a function of language mode. The perception study showed that language-specific phonetic strategies, which had been observed among highly fluent bilinguals, could also be possible for this population.
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A Living Nightmare: A Phenomenological Study of Black Males' Lived Experiences of Racial Profiling During Traffic StopsJackson, James C., III 01 January 2018 (has links)
For years, urban communities and specific ethnic groups within the US (mostly Blacks and Hispanics) have been targeted for racial profiling by our local police. Since the 1990’s, the outcry for justice by our Black and Hispanic communities increased the interests to find ways to address and fight against the act of racial profiling. This phenomenological study used a qualitative approach to collect information and gain the understanding and lived experiences of Black males between the ages of 20 – 49 who experienced racial profiling during routine traffic stops. Twelve Black Males between the ages of 20 to 49 were interviewed for the research study. Everyone was interviewed separately to gather experiences and meanings from their own points of view. In addition, 25 Black males within the same age group participated in a 1 hour focus group discussion. The information gathered from the interviews and focus group sessions were compiled into a Microsoft word transcript and reviewed and analyzed by the researcher to form seven themes. In order to come up with key findings, I isolated similar responses from the experiences shared by the research participants during the interviews and focus group session. In isolating some of the key responses revealed, I dissected racial profiling from a shared experience point of view based on common approaches practiced by law enforcement officers. The research study will contribute to field on conflict resolution through the voices of those who experienced racial profiling, and finding ways to encourage mediation through projecting the underlying concerns or issues to community leaders, government officials, concerned groups, and law enforcement agencies.
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Kaffepaus : Analys av stopporsaker på paketeringslina hos Arvid Nordquist HAB / Coffee break : Analysis of stoppages at a packaging line at Arvid Nordquist HABIsacson, Mimmi, Jonviken, Caroline January 2019 (has links)
Arvid Nordquist HAB rostar, maler och packar kaffe i sin fabrik i Solna, Stockholm. Efter installation av ett program för produktions- och driftuppföljning, RS Production, har det uppmärksammats att andelen korta stopp (Mikrostopp, varar upp till två minuter) ibland är hög. Projektets mål var således att undersöka de mest frekventa orsakerna till mikrostopp samt att försöka ta fram förslag på åtgärds- eller handlingsplaner. Ett mål var även att utreda om de stoppkategorier som finns i RS production är relevanta. För att uppfylla målen ställdes följande frågor: Kan operatörerna beskriva verkligheten med de kategorier som finns i RS Production idag? Vilka är de huvudsakliga stopporsakerna för kategorin Mikrostopp? Vilka åtgärder kan vidtas för att minska stopptiden relaterad till stopporsaker ikategorierna Mikrostopp, Felorsak okänd och Orsak Övrigt? Data samlades in från RS Production, observationer samt med hjälp av enkäter och samtal med operatörer och tekniker. De tre främsta orsakerna till stopp är silobyte, paket fastnar och paket välter. Vidare framkom att det inte är någon större skillnad på antal stopp mellan skiften. Helgskiften hade färre stopp totalt, men har också totalt färre timmar. Nattskiften hade flest stopp när antal stopp per arbetad timme beräknades. Eco, Kok och Festivita hade flest stopp per packat ton kaffe. Antalet mikostopp reduceras enklast med en buffert. Utöver mikrostopp studerades även kategorierna Felorsak okänd och Orsak övrigt. Dessa används på ett likartat sätt och det framkom från enkäterna att det rådde delade meningar om hur Felorsak okänd används. Felorsak okänd och Orsak övrigt verkade användas trots att passande kategorier finns i RS Production. En anledning till detta är att stopp inte kategoriseras av operatör på en gång, en annan kan vara att operatör inte känner till eller orka leta fram rätt kategori. Här rekommenderas att dessa två kategorier slås samman till en. / Arvid Nordquist HAB roasts, grinds and package coffee in their factory in Solna, Stockholm. It has come to light, following the installation of software (RS production) for production and operation management, that the number of short stops (“Mikrostopp”, lasting for 2 minutes or less) sometimes is very high. The main goal of this project was therefore to examine what the most frequent causes for stops in the “Mikrostopp” category and to try to produce solutions and action plans. Another goal was to examine if the categories for stops in RS Production are relevant. To reach the goals following questions were asked: Can the operators describe the reality with the categories that are available in RS Production today? What are the main causes for stops in the category “Mikrostopp”? What measures can be taken to reduce the downtime related to causes for stoppages in the categories “Mikrostopp”, “Felorsak okänd” and “Orsak Övrigt”? Data was collected from RS Production, observations, a survey and discussions with operators and technicians. The three most common causes for stops are change of silo and packets getting stuck or falling. The analysis shows that stops are evenly distributed over the working shifts. The weekend shifts had fewer stops when the total number of stops for each type of shift was compared. When number of stops per working hour was calculated, the night shift had the highest number. Eco, Kok and Festivita had the highest number of stops when number of stops per kind and tonne of packaged coffee was analysed. The downtime related to micro stops can be reduced with the help of buffers. In addition to the Mikrostopp category, the categories named Felorsak okänd and Orsak övrigt were studied. These categories were used in an analogous way, and the survey showed that how and when Felorsak okänd were to be used was perceived differently between operators. Both “Felorsak okänd” and “Orsak övrigt” were used even though there were other fitting categories in RS Production for the stop. One reason for this could be that the operator did not categorize the stop until later. Another reason could be that they did not know where to find a more suitable categoryor did not care to look. The solution to this problem is simply to merge these two categories and use as one
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Effektivisering av materialförsörjningen i Hydroscands produktionsprocess. : Streamlining the material supply in Hydroscand's production processMahhou, Ismail January 2023 (has links)
Hydroscand in Örebro is part of the Hydroscand Group, which is the market leader in the Nordic region for customized hydraulic solutions. Hydroscand's main products consist of adapters, couplings, hydraulic hoses, pipes, and hose clamps. Due to the wide range of products offered by Hydroscand, the company's facility in Örebro has experienced recurring production stops linked to material shortages. The Örebro facility comprises three buildings: a production house, a warehouse, and Spendrup, where a large quantity of hoses is stored. This leads to long waiting times in the form of production stops because the transportation time between the buildings is lengthy.Through a systematic approach involving a current state analysis, it was confirmed that production stops related to material shortages should be prevented to streamline production. Following the current state analysis, a root cause analysis was conducted, identifying the root causes of material shortages in production. These root causes included an inadequate material supply strategy that was not tailored to the product flow, a lack of a visual system clarifying empty shelves for material suppliers, improper prioritization of hoses in the hose tower near the production lines, and material suppliers' position in the information flow, which hinderedpreventive actions against material shortages.The proposed solution consisted of four sub-solutions to prevent these root causes, including a shift from a push to a pull material supply strategy. This involved following a material list to ensure the availability of the correct materials in the production house. Implementation of a Kanban system was one of the sub-solutions to simplify the detection of empty shelves. The change in strategy led to a modification in the information flow, resulting in improved communication between production and material suppliers. The final sub-solution was to replace the hoses in the hose tower with the ones that are frequently sold, as the hoses in the highest demand will also be the most needed in production.The proposed solution will result in increased production productivity and the elimination of production stops associated with material shortages, which was the objective of the work. / Hydroscand i Örebro tillhör företagsgruppen Hydroscand Group som är marknadsledande iNorden gällande kundanpassade hydrauliklösningar. Hydroscands huvudsakliga produkter består av adapters, kopplingar, hydraulslangar, rör och slangklämmor. På grund av Hydroscands stora produktvariation så har företagets anläggning i Örebro haft återkommande produktionsstopp som har kopplats till materialbrist i produktionen. Örebros anläggning består av tre byggnader ett produktionshus, ett lagerhus och Spendrup där stora slangkvantitet lagras. Detta medför att materialbristen kan orsaka långa väntetider i form av produktionsstopp, eftersom transporttiden mellan byggnaderna tar lång tid.Genom ett metodiskt arbete där en nulägesanalys genomfördes bekräftades bilden av att produktionsstoppen kopplade till materialbrist bör förebyggas för att effektivisera produktionen. Efter nulägesanalysen genomfördes en rotorsaksanalys som fann rotorsakerna till att materialbrist förekom i produktionen. Dessa rotorsaker var felaktig materialförsörjningsstrategi som inte var anpassad till produktflödet, en avsaknad av ett visuellt system som förtydligar tomma hyllor för materialförsörjare, fel prioritering av slang i slangtornet nära anslutning till produktionslinorna och materialförsörjares position i informationsflödet som försvårade det förebyggande arbetet mot materialbrister.Lösningförslaget bestod av fyra dellösningar som skulle förebygga dessa rotorsaker, lösningen bestod av att förändra materialförsörjnings strategi från push till pull. Detta genom att följa en materiallista för att säkerställa att rätt material finns tillgängligt i produktionshuset. En implementering av ett Kanbansystem var en av dellösningar, detta för att förenkla upptäckten av tomma hyllor. Bytet av strategin ledde till en förändring av informationsflödet, vilket kommer resultera i en förbättrad kommunikation mellan produktion och materialförsörjare. Sista dellösningen var att byta de slang som låg i slangtornet mot de slang som oftast säljs, eftersom slang som har mest efterfrågan kommer även att behövas mest i produktionen.Lösningsförslaget kommer att resultera i ökad produktionsproduktivitet samt en eliminering av produktionsstopp kopplade till materialbrist, vilket var syftet med arbetet.
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RACE AND REPEATS: DOES THE REPETITIVE NATURE OF POLICE MOTOR VEHICLE STOPS IMPACT RACIALLY BIASED POLICING?GROWETTE BOSTAPH, LISA M. January 2004 (has links)
No description available.
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Short continuously reinforced concrete pavement design recommendations based on non-destructive ultrasonic data and stress simulation. / Recomendações de projeto baseadas em dados ultrassônicos não destrutivos e simulação de tensões para pavimento de concreto continuamente armado de curta extensão.Salles, Lucio Salles de 19 May 2017 (has links)
Four sections of continuously reinforced concrete pavement (CRCP) were constructed at the University of São Paulo campus in order to introduce this kind of pavement structure to Brazil\'s technical transportation community. Sections were designed as 50 m long concrete slab, short in comparison to traditional CRCP, in order to simulate bus stops and terminals - locations of critical interest for public infrastructure. The thesis presented herein concludes this research project initiated in 2010. As the initial goal of this study was the development of coherent, reliable and intuitive design recommendations for the use of CRCP technology in Brazil, a profound understating of its structural and performance peculiarities was needed. For that, the cracking process of the experimental CRCP sections was recorded over a span of seven years. Due to the sections\' short length and lack of anchorage, the experimental \"short\" CRCP presented a cracking behavior quite different than traditional CRCP. There were much less visible cracks than expected. To address this issue, a novel technology in ultrasonic non-destructive testing of concrete structures was applied. Through ultrasonic signal interpretation it was possible to discover several incipient non-visible cracks within the slabs - many of these became apparent on the slab surface in later crack surveys - and to characterize visible and non-visible cracks regarding crack depth. The updated crack map with non-visible cracks showed similarities with traditional CRCP. Additionally, the ultrasonic data analysis provided important information on thickness variation, reinforcement location and concrete condition that were applied in theoretical simulations (finite element software) of the short CRCP. Simulations were attempted considering different slab geometries, firstly with transverse cracks as joints with high load transfer efficiency (LTE) and secondly with a continuous slab without cracks or joints. The latter simulation was more accurate reaching a shift factor between field and simulated stresses in the order of 0.7 to 1.0. Deflection data and LTE analysis from cracks and panels in between cracks further attested the slab continuous behavior, which contradicts current CRCP design models and performance predictors. Furthermore, critical traffic and environmental loading conditions concerning Brazil\'s climate and bus traffic characteristics were investigated and related using a selected fatigue model resulting in design recommendations in a chart format for the short CRCP aimed at long-term projects for over 20 years of operation. The design chart was successfully applied to investigate three failures presented by the experimental short CRCP due to thickness deficiencies pointed out by the ultrasonic testing. / Quatro seções de pavimento de concreto continuamente armado (PCCA) foram construídas no campus da Universidade de São Paulo, com o objetivo de introduzir esta estrutura, de reconhecido sucesso internacional, à comunidade técnica de engenharia de transportes brasileira. As seções foram projetadas com uma placa de concreto de 50 m de extensão, curta em comparação ao PCCA tradicional, com a finalidade de simular paradas e terminais de ônibus - locais de grande interesse para a infraestrutura pública. A tese aqui apresentada conclui este projeto de pesquisa iniciado em 2010. Como o objetivo inicial deste estudo foi o desenvolvimento de recomendações de projeto coerentes, confiáveis e intuitivas para a utilização do PCCA no Brasil, foi necessário um profundo entendimento de suas peculiaridades estruturais e de desempenho. Para isso, o processo de fissuração das secções experimentais foi acompanhado durante sete anos. Devido à curta extensão e falta de ancoragem das seções, o PCCA \"curto\" apresentou um padrão de fissuração diferente do PCCA tradicional com muito menos fissuras visíveis na superfície do que o esperado. Para abordar esta questão, uma nova tecnologia ultrassônica para ensaios não destrutivos de estruturas de concreto foi aplicada. Pela interpretação do sinal de ultrassom, foi possível descobrir várias fissuras incipientes (não visíveis) dentro das placas - muitas dessas foram observadas na superfície da placa em levantamentos de fissuras posteriores - e caracterizar fissuras visíveis e não-visíveis quanto à profundidade da fissura. O mapa de fissuração atualizado com fissuras não visíveis mostrou semelhanças com PCCA tradicional. Além disso, a análise dos dados de ultrassom forneceu informações importantes sobre a variação da espessura, localização da armadura longitudinal e condição do concreto, que foram aplicados em simulações teóricas (software de elementos finitos) do PCCA curto. Simulações foram propostas considerando diferentes geometrias, primeiramente com fissuras transversais como juntas com alta eficiência de transferência de carga (LTE) e posteriormente com uma placa contínua, sem fissuras ou juntas. Esta última simulação foi mais precisa alcançando um fator de conversão entre tensões de campo e simuladas na ordem de 0,7 a 1,0. Dados de deflexão e análise de LTE em fissuras e placas entre fissuras atestaram novamente o comportamento contínuo das placas, o que vai em contradição com os modelos atuais de dimensionamento e de previsão de desempenho para o PCCA. Ademais, o tráfego crítico e condições de carga ambiental correspondentes ao clima e tráfego de ônibus típicos brasileiros foram investigados e relacionados usando um modelo de fadiga resultando em recomendações de projeto para o PCCA de curta extensão sendo direcionado para projetos de longo prazo para mais de 20 anos de operação. O gráfico de projeto foi aplicado com sucesso para investigar três falhas apresentadas pelo PCCA curto experimental devido a deficiências de espessura apontadas pelo teste ultrassônico.
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Short continuously reinforced concrete pavement design recommendations based on non-destructive ultrasonic data and stress simulation. / Recomendações de projeto baseadas em dados ultrassônicos não destrutivos e simulação de tensões para pavimento de concreto continuamente armado de curta extensão.Lucio Salles de Salles 19 May 2017 (has links)
Four sections of continuously reinforced concrete pavement (CRCP) were constructed at the University of São Paulo campus in order to introduce this kind of pavement structure to Brazil\'s technical transportation community. Sections were designed as 50 m long concrete slab, short in comparison to traditional CRCP, in order to simulate bus stops and terminals - locations of critical interest for public infrastructure. The thesis presented herein concludes this research project initiated in 2010. As the initial goal of this study was the development of coherent, reliable and intuitive design recommendations for the use of CRCP technology in Brazil, a profound understating of its structural and performance peculiarities was needed. For that, the cracking process of the experimental CRCP sections was recorded over a span of seven years. Due to the sections\' short length and lack of anchorage, the experimental \"short\" CRCP presented a cracking behavior quite different than traditional CRCP. There were much less visible cracks than expected. To address this issue, a novel technology in ultrasonic non-destructive testing of concrete structures was applied. Through ultrasonic signal interpretation it was possible to discover several incipient non-visible cracks within the slabs - many of these became apparent on the slab surface in later crack surveys - and to characterize visible and non-visible cracks regarding crack depth. The updated crack map with non-visible cracks showed similarities with traditional CRCP. Additionally, the ultrasonic data analysis provided important information on thickness variation, reinforcement location and concrete condition that were applied in theoretical simulations (finite element software) of the short CRCP. Simulations were attempted considering different slab geometries, firstly with transverse cracks as joints with high load transfer efficiency (LTE) and secondly with a continuous slab without cracks or joints. The latter simulation was more accurate reaching a shift factor between field and simulated stresses in the order of 0.7 to 1.0. Deflection data and LTE analysis from cracks and panels in between cracks further attested the slab continuous behavior, which contradicts current CRCP design models and performance predictors. Furthermore, critical traffic and environmental loading conditions concerning Brazil\'s climate and bus traffic characteristics were investigated and related using a selected fatigue model resulting in design recommendations in a chart format for the short CRCP aimed at long-term projects for over 20 years of operation. The design chart was successfully applied to investigate three failures presented by the experimental short CRCP due to thickness deficiencies pointed out by the ultrasonic testing. / Quatro seções de pavimento de concreto continuamente armado (PCCA) foram construídas no campus da Universidade de São Paulo, com o objetivo de introduzir esta estrutura, de reconhecido sucesso internacional, à comunidade técnica de engenharia de transportes brasileira. As seções foram projetadas com uma placa de concreto de 50 m de extensão, curta em comparação ao PCCA tradicional, com a finalidade de simular paradas e terminais de ônibus - locais de grande interesse para a infraestrutura pública. A tese aqui apresentada conclui este projeto de pesquisa iniciado em 2010. Como o objetivo inicial deste estudo foi o desenvolvimento de recomendações de projeto coerentes, confiáveis e intuitivas para a utilização do PCCA no Brasil, foi necessário um profundo entendimento de suas peculiaridades estruturais e de desempenho. Para isso, o processo de fissuração das secções experimentais foi acompanhado durante sete anos. Devido à curta extensão e falta de ancoragem das seções, o PCCA \"curto\" apresentou um padrão de fissuração diferente do PCCA tradicional com muito menos fissuras visíveis na superfície do que o esperado. Para abordar esta questão, uma nova tecnologia ultrassônica para ensaios não destrutivos de estruturas de concreto foi aplicada. Pela interpretação do sinal de ultrassom, foi possível descobrir várias fissuras incipientes (não visíveis) dentro das placas - muitas dessas foram observadas na superfície da placa em levantamentos de fissuras posteriores - e caracterizar fissuras visíveis e não-visíveis quanto à profundidade da fissura. O mapa de fissuração atualizado com fissuras não visíveis mostrou semelhanças com PCCA tradicional. Além disso, a análise dos dados de ultrassom forneceu informações importantes sobre a variação da espessura, localização da armadura longitudinal e condição do concreto, que foram aplicados em simulações teóricas (software de elementos finitos) do PCCA curto. Simulações foram propostas considerando diferentes geometrias, primeiramente com fissuras transversais como juntas com alta eficiência de transferência de carga (LTE) e posteriormente com uma placa contínua, sem fissuras ou juntas. Esta última simulação foi mais precisa alcançando um fator de conversão entre tensões de campo e simuladas na ordem de 0,7 a 1,0. Dados de deflexão e análise de LTE em fissuras e placas entre fissuras atestaram novamente o comportamento contínuo das placas, o que vai em contradição com os modelos atuais de dimensionamento e de previsão de desempenho para o PCCA. Ademais, o tráfego crítico e condições de carga ambiental correspondentes ao clima e tráfego de ônibus típicos brasileiros foram investigados e relacionados usando um modelo de fadiga resultando em recomendações de projeto para o PCCA de curta extensão sendo direcionado para projetos de longo prazo para mais de 20 anos de operação. O gráfico de projeto foi aplicado com sucesso para investigar três falhas apresentadas pelo PCCA curto experimental devido a deficiências de espessura apontadas pelo teste ultrassônico.
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