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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Análise comparativa técnico-econômica entre os pavimentos de concreto asfáltico e blocos intertravados de concreto

Oliveira, Cinara Souza de 20 July 2018 (has links)
Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2018-11-09T16:02:25Z No. of bitstreams: 1 Cinara Souza de Oliveira_.pdf: 6076965 bytes, checksum: 49100f247c5d8c407a67a4c02d3903e8 (MD5) / Made available in DSpace on 2018-11-09T16:02:25Z (GMT). No. of bitstreams: 1 Cinara Souza de Oliveira_.pdf: 6076965 bytes, checksum: 49100f247c5d8c407a67a4c02d3903e8 (MD5) Previous issue date: 2018-07-20 / Nenhuma / Esta dissertação tem por objetivo comparar economicamente o pavimento de concreto asfáltico e de blocos intertravados de concreto na pavimentação urbana da Avenida Severo Dullius, considerando os custos das soluções propostas pelos métodos. A avenida em estudo é uma das principais vias radiais que compõe o anel viário que dá acesso ao Aeroporto Internacional Salgado Filho, é tida como essencial dentro do plano de mobilidade urbana do município de Porto Alegre/RS, localizada em zona urbana alagadiça, com subleito constituído de solos de baixo poder de suporte e tráfego comercial pesado. O dimensionamento foi realizado para um trecho 2,3 Km e, contou com estudos geotécnicos, com intuito de caracterizar física e mecanicamente o solo do subleito, considerou-se a contagem e classificação do tráfego atuante na via. Em seguida, foi analisado o comportamento estrutural desses pavimentos urbanos na referida situação e apresentados os métodos construtivos adequados e recomendados. Aplicou-se para o pavimento em concreto asfáltico o método de dimensionamento de pavimento flexíveis – DNER atual DNIT, e para o bloco intertravado de concreto empregou-se o método da ABCP (1998). Para permitir a comparação técnica e financeira entre os pavimentos, foram consideradas suas características estruturais e os respectivos períodos de projetos. Contabilizaram-se os custos da implantação e da conservação. Com os orçamentos disponíveis, efetuou-se uma comparação de serviços com o objetivo de identificar sua viabilidade econômica, propondo o assim o pavimento adequado para a via selecionada. Concluiu-se que para este estudo a utilização do bloco intertravado de concreto como solução final em função do custo comparado, apresentou-se uma economia de 16,93% no custo final da implantação, portanto economicamente mais vantajosa em relação ao concreto asfáltico. Diante disto, concluiu-se também, que uma análise econômica de um pavimento rodoviário, deve-se sempre abordar todos os custos e benefícios pertinentes, considerando todas as fases de sua implantação. / This dissertation aims to compare economically the asphalt concrete and interlocking concrete blocks in the urban paving of Severo Dullius Avenue, considering the costs of the solutions proposed by the methods. The avenue under study is one of the main radial roads that makes up the ring road that accesses the Salgado Filho International Airport, and it is considered imperative to the urban mobility plan of the city of Porto Alegre / RS, located in and urban swamp area, with subsoil consisting of low support power soils and heavy commercial traffic. The sizing was carried out for a 2.3 km stretch, and it was based on geotechnical studies in order to physically and mechanically characterize the subsoil soil, considering the counting and classification of the traffic acting on the road. Next, the structural behavior of these urban pavements in the mentioned situation was analyzed and the suitable and recommended construction methods were presented. The method of sizing of flexible pavement – DNER current DNIT was applied to the asphaltic pavement, and the ABCP (1998) method was used for the interlocked block of concrete. In order to allow the technical and financial comparison between the floors, their structural characteristics and the respective project periods were considered. The costs of implementation and conservation were taken into account. With the budgets available, a comparison of services was carried out in order to identify their economic viability, thus proposing the adequate pavement for the selected route. It was concluded for this study that, as a final solution, the use of the interlocked concrete block compared with the concrete, showed a saving of 16,93% in the final cost of the implantation, thus economically more advantageous in relation to the asphalt concrete. In view of this, it was also concluded that an economic analysis of a road pavement should always address all relevant costs and benefits, considering all phases of its implementation.
122

Parametric Study On Selected Mathematical Models For Dynamic Creep Behavior Of Asphalt Concrete

Ozturk, Hande Isik 01 December 2007 (has links) (PDF)
Rut formation has long been recognized as a distress mechanism in flexible pavements. One of the causes of rut formation in flexible pavements is permanent deformation of uppermost asphalt concrete layers due to repeatedly applied traffic loading. The long term permanent deformation of asphalt concrete under repeated load is commonly called as dynamic creep. The primary objective of this thesis is to examine dynamic creep behavior of asphalt concrete specimens tested in laboratory and also study some suitable mathematical models for representing dynamic creep behavior. In this study, a set of uniaxial repeated load creep tests were performed on standard Marshall specimens prepared at three different bitumen contents. The effects of bitumen content and test condition parameters on dynamic creep behavior are examined. Among several mathematical creep models suggested by researchers, two well known models and a model proposed by the author are selected for representing the laboratory creep behavior. For each of these models, the interactions of the model parameters with varying bitumen content and test conditions are studied to detect probable definite trends, and to evaluate whether some relations for the model parameters as functions of bitumen content and test conditions can be developed or not. The results of analyses showed that all three mathematical models used in this study are successful in representing the laboratory dynamic creep behavior of asphalt concrete. The Power Model which has only two parameters is found to be the most stable and suitable model for parametric study among the three selected models. More consistent and definite interactions are observed between the parameters of this model and test conditions. However, within the scope of this study, no relations could be developed for the parameters of selected models as functions of bitumen content and test conditions because of limited test data.
123

Recycling of construction waste for roads rehabilitation

Mhlongo, S'phamandla Mlungisi. January 2013 (has links)
M. Tech. Civil Engineering.. / Investigates the feasibility of recycling construction waste for re-use as raw material in rehabilitation of roads in Bethal (Govan Mbeki Municipality). Specific Objectives: (a) To identify the causes of roads failure within the study area.(b) To assess feasibility of reuse of construction waste and propose method of road rehabilitation.(c) To recycle unsuitable material through characterisation of the construction waste. (d) To compare the cost implications when recycled construction waste is used with that of normal roads' rehabilitation.
124

Investigation into Asphalt Concrete Material and Volumetric Properties that Promote Moisture Damage

Lambert, Jean-Luc 19 September 2013 (has links)
The research presented in this thesis: (1) quantifies and qualifies the Surface Free Energy (SFE) of neat and Liquid Anti-Strip (LAS) modified asphalt binders (binder); and (2) identifies volumetric mix properties that inhibit or assist in the susceptibility of Hot Mix Asphalt (HMA) to moisture damage based on time dependent phenomenological mechanical responses. These two research elements provide insight into the physical, chemical, mechanical and volumetric mix properties that inhibit or facilitate moisture damage in HMA. Moisture damage is a mechanism that causes distress and failure in asphalt concrete (AC) pavements due to a loss of durability resulting from the presence of moisture, in the form of a vapour or liquid, originating internally or externally. This reduces the pavements performance by promoting distresses such as: longitudinal cracking, spalling, rutting, shoving, stripping and ravelling. When moisture originates or is introduced in the AC a weakening of adhesion and cohesion of the material occurs, due in part to: binder properties, aggregate properties, volumetric mix properties, environmental conditions, traffic volume and loads, pavement design and construction practices. The research performed was split in two parts. The first part consisted of conducting SFE measurements on two PG 58-34 binders with different sources. One binder was modified with a LAS agent at concentrations of 0.5%, 2.0% and 5.0% by mass of binder and the other binder was kept neat. The neat and LAS modified binders were subjected to short-term aging by oxidation and then tested with a goniometer to determine their SFE and wettability. The SFE measurements revealed that an LAS concentration of 0.5% maximizes: (1) the work of adhesion of an unaged and aged binder, and (2) the ability of the binder to repel water. Furthermore, the process of aging increases the hydrophobicity or tendency of the binder to repel water regardless of the LAS concentration. Hence, an LAS concentration of 0.5% minimizes the potential for moisture damage in HMA. The second part of the research consisted of investigating the potential for moisture damage of seven bituminous type B (Bit B) and eight bituminous type C (Bit C) mix specified by Manitoba Infrastructure and Transportation. Laboratory testing of the resilient modulus and creep compliance was conducted to determine the fundamental mechanical response of the material. The resilient modulus and creep compliance test program were conducted on samples before and after moisture conditioning. As a result of the testing program, it was observed that the susceptibility of AC to moisture damage based on volumetric mix properties can be dependent on the air voids ratio, aggregate gradation and binder content of the mix.
125

Investigation into Asphalt Concrete Material and Volumetric Properties that Promote Moisture Damage

Lambert, Jean-Luc 19 September 2013 (has links)
The research presented in this thesis: (1) quantifies and qualifies the Surface Free Energy (SFE) of neat and Liquid Anti-Strip (LAS) modified asphalt binders (binder); and (2) identifies volumetric mix properties that inhibit or assist in the susceptibility of Hot Mix Asphalt (HMA) to moisture damage based on time dependent phenomenological mechanical responses. These two research elements provide insight into the physical, chemical, mechanical and volumetric mix properties that inhibit or facilitate moisture damage in HMA. Moisture damage is a mechanism that causes distress and failure in asphalt concrete (AC) pavements due to a loss of durability resulting from the presence of moisture, in the form of a vapour or liquid, originating internally or externally. This reduces the pavements performance by promoting distresses such as: longitudinal cracking, spalling, rutting, shoving, stripping and ravelling. When moisture originates or is introduced in the AC a weakening of adhesion and cohesion of the material occurs, due in part to: binder properties, aggregate properties, volumetric mix properties, environmental conditions, traffic volume and loads, pavement design and construction practices. The research performed was split in two parts. The first part consisted of conducting SFE measurements on two PG 58-34 binders with different sources. One binder was modified with a LAS agent at concentrations of 0.5%, 2.0% and 5.0% by mass of binder and the other binder was kept neat. The neat and LAS modified binders were subjected to short-term aging by oxidation and then tested with a goniometer to determine their SFE and wettability. The SFE measurements revealed that an LAS concentration of 0.5% maximizes: (1) the work of adhesion of an unaged and aged binder, and (2) the ability of the binder to repel water. Furthermore, the process of aging increases the hydrophobicity or tendency of the binder to repel water regardless of the LAS concentration. Hence, an LAS concentration of 0.5% minimizes the potential for moisture damage in HMA. The second part of the research consisted of investigating the potential for moisture damage of seven bituminous type B (Bit B) and eight bituminous type C (Bit C) mix specified by Manitoba Infrastructure and Transportation. Laboratory testing of the resilient modulus and creep compliance was conducted to determine the fundamental mechanical response of the material. The resilient modulus and creep compliance test program were conducted on samples before and after moisture conditioning. As a result of the testing program, it was observed that the susceptibility of AC to moisture damage based on volumetric mix properties can be dependent on the air voids ratio, aggregate gradation and binder content of the mix.
126

Hålrumsvariationer vid asfalttillverkning : En fallstudie vid Skanska enligt DMAIC avseende förbättringsmöjligheter vid kalltillsatt asfaltåtervinning / Void volume variations in asphalt manufacturing : A case study at Skanska based on DMAIC regarding opportunities for improvement when using cold RAP

Johansson, Paulina January 2018 (has links)
Att optimera hålrumshalten i färdig beläggning är essentiellt bland annat för att en vägkonstruktion inte ska få sprickor, spårbildning eller andra deformationer vid temperaturväxlingar  (Monismith, 1992). Eftersom både återvunnen och jungfrulig asfaltmassa består av stenmaterial, bitumen och tillsatsmedel är återvunnen asfalt värd den jungfruliga massans vikt ton för ton vid utbyte i ett arbetsrecept (Brock & Richmonds, 2007). I takt med att asfaltåtervinning blivit vanligare ökar dock komplexiteten, då återvunnet material är betydligt svårare än jungfruligt att karaktärisera (Karlsson & Isacsson, 2006). Eftersom användningen av återvunnet material förväntas öka samtidigt som lite forskning gjorts i ämnet är det därför av vikt att undersöka hålrumshalter vid kalltillsatt asfaltåtervinning. För studien undersöktes asfaltmassan ABT11 160/220 vid kalltillsättning av upp till 25 % asfaltåtervinning. Sex Sigmas problemlösningsmetodik DMAIC, vilket står för ett projektbaserat förhållningssätt i de fem faserna define, measure, analyze, improve och control, användes för att få en djupgående förståelse för hålrumsproblematiken. I metodiken användes i sin tur statistisk processtyrning och försöksplanering för att svara på studiens syfte, vilket var att granska och utvärdera orsakerna till varför hålrumshalter under asfalttillverkning varierar vid tillsättning av kallt asfaltgranulat samt ge rekommendationer för en förbättrad produktion med avseende på hålrumshalt. Efter granskning av historiska data, beräkningar, intervjuer och observationer ansågs de viktigaste orsakerna till hålrumsvariationer uppkomma från de fem källorna datahantering, kommunikation, resurshantering, materialkunskap och organisationskultur, där de två sistnämnda ansågs vara rotorsaker. På grund av examensarbetets avgränsning granskades endast materialkunskapen mer djupgående. För att fördjupa materialkunskapen valdes faktorerna asfaltåtervinning, jungfruligt bitumen, jungfruligt filler samt tillverknings- och instampningstemperatur ut för fortsatta studier genom två experiment. I det första experimentet granskades hur hålrumshalten påverkades av olika instampningstemperaturer genom en OFAT-studie och i det andra experimentet ansattes ett 24-1 faktorförsök enligt Splitplot där hålrummet mättes vid vanlig instampningstemperatur (135 ˚C) samt genom en vägsimulering. Resultatet från det första experimentet uppvisade ett förhållande enligt ett tredjegradspolynom mellan hålrum och instampningstemperatur med stora hålrumsförändringar under 125 ˚C och över 145 ˚C. Detta medför att det är av än större vikt att kontrollera temperaturen för lågtempererad massa och massa med mycket återvinning för att uppnå godkända hålrum vid utläggning. Det andra experimentet visade att även bitumen och återvinning är signifikanta effekter för hålrummet, där minskade bitumenhalter och ökade återvinningshalter medför högre hålrumshalter samt att återvinningshalter över 15 % medför oönskad ökning av hålrumshalter vid utläggning på väg. För att avhjälpa orsakerna till hålrumsvariationerna rekommenderas att data samlas, utvärderas, kommuniceras och följs upp i större utsträckning genom användning av statistisk processtyrning, värdeflödesanalyser och fortsatta materialstudier. Organisationskulturen bör förändras för att skapa en förståelse för vikten av rekommenderade metoder. Kan rekommendationerna följas innebär det en uppskattad ekonomisk besparing på 11 520 000kr/år, samtidigt som det skulle innebära miljömässiga fördelar i form av bland annat ett minskat uttag av ändliga resurser och minskade CO2-utsläpp. / Optimizing void volumes are essential for the serviceability of asphalt concrete pavements, as fatigue cracking, rutting and other permanent deformations can be caused by e.g. temperature changes (Monismith, 1992). Since both reclaimed asphalt pavement (RAP) and virgin asphalt concrete consist of mineral aggregate, bitumen and additives, RAP is worth the virgin material it replaces ton for ton (Brock & Richmonds, 2007). As the use of RAP becomes more and more popular, the complexity of asphalt manufacturing increases (Karlsson & Isacsson, 2006). This, because the recycled material is harder to characterize than virgin material. Since the usage of RAP is expected to increase in hot-mix asphalt (HMA), while little research has been made in the field of cold feed RAP, it is of great importance to investigate the void volumes with this method. During this study, ABT11 160/220 with the addition of up to 25% cold feed RAP was therefore investigated. Six Sigma’s project improvement methodology DMAIC, acronym for the five phases define, measure, analyze, improve and control, were used to get an in depth understanding for the variations in void volumes. In this method, Statistical Process Control and Design of Experiments were used to answer the research purpose, which was to investigate and evaluate the reasons to why void volumes during asphalt manufacturing varies when adding cold RAP and give recommendations for an improved production regarding void volumes. After an investigation of historic data, calculations, interviews and observations, the most important causes for variations in void volumes came from data collection, communication, resource management, material knowledge and organizational culture, where the last two are seen as root causes. Because of the research delimitations, only the material knowledge was looked into further. To extend the knowledge of the material, the factors RAP, virgin bitumen, virgin filler, manufacturing temperature and temperature for Marshall testing were analyzed through two experiments. In the first experiment, the relationship between void volumes and the temperature for Marshall testing were investigated through an OFAT study, and the second experiment was made through a 24-1 factorial design according to Split plot, in which the void volumes were measured through the normal Marshall testing temperature (135 ˚C) and through a road simulation.  The OFAT result showed that a third degree linear relationship is present between the void volumes and the Marshall testing temperature, with large changes for temperatures lower than 125 ˚C and greater than 145 ˚C. This entails an increased importance of controlling the temperature for warm-mix asphalt (WMA) and asphalt with increased volumes of RAP. The Split plot experiment showed that also bitumen and RAP are significant effects for the void volume, where decreased volumes of bitumen and increased volumes of RAP entails higher void volumes in the pavement. Over 15 % RAP also entails greater void volumes. To decrease the causes for variations in void volumes, the recommendation is to collect, evaluate, communicate and follow up data at a higher extent through implementation of statistical process control, value flow analysis and continued material studies. The organizational culture ought to be changed to create an understanding of the recommended methods. If the recommendations are followed, estimated economic savings of 11 520 000kr/year can be a reality, as well as environmental benefits of e.g. a decreased use of finite resources and reduced CO2 emissions.
127

Estudo da viabilidade para reaproveitamento do resíduo de areia verde de fundição intemperizado em concreto asfáltico usinado a quente

Luvizão, Rubia Raquel 01 July 2008 (has links)
Made available in DSpace on 2016-12-08T17:19:32Z (GMT). No. of bitstreams: 1 Rubia Raquel Luvizao.pdf: 2856384 bytes, checksum: 11aac33ded8309a4b3c237cbdecbfdb7 (MD5) Previous issue date: 2008-07-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Scrap weathered green foundry sand (WGFS), generated in a southern Brazilian steel casting industry, was studied in this work. According to Brazilian standards, the Green foundry sand waste is classified as a non-inert residue due to the potential leaching of toxic metal ions. Its disposal in controlled landfills is the main form of final destination. The aim of this research study presented here was the characterization of weathered green foundry sand waste and to evaluate its applications on asphalt concrete. The material was characterized by X-ray fluorescence spectroscopy (XFA), powder X-ray diffraction (XRD), thermogravimetric analysis (TG), granulometric analysis, scanning electron microscopy (SEM). Environmental behavior tests were performed: solubilisation, neutral and alkaline leaching. The aggregates were characterized by granulometric analysis and sand content equivalent. The characteristics of asphalt binder were obtained as melting point and viscosity at the specified standard temperature. The determination of the optimum mix ratio used for the weathered green foundry sand waste on asphalt concrete was obtained using the Marshall method. The mechanical properties available were resilience modulus, static strength and reduction of the strength by induced humidity. The environmental behavior analyses results of solubilisation and leaching coupled with X-ray fluorescence spectroscopy shown that the scrap WGFS presents a lower content of Clay mineral linked to the sand particles surface and reduced contents of aluminum, iron, sodium and sulphate. The chemical, mineralogical and physical characterizations shown that the WGFS presents pH of 8,44, reduced Fe2O3 and Al2O3 contents and lower quantities of clay mineral montmorilonite, and quartz. The resilience modulus (circa of 5400 MPa) and static strength (circa of 1.20 MPa) results obtained using 15 wt.% of WGFS were higher that the found with freshly green foundry sand or natural sand. However, the reduction of 43 % on strength for the induced humidity test was higher to the specified for the standard (30 %). / O resíduo de areia verde de fundição, objeto de estudo deste trabalho, foi fornecido por uma fundição localizada no município de Joinville-SC, região sul do Brasil. De acordo com as normas brasileiras, o resíduo de areia verde de fundição e classificado como não inerte devido a presença de alguns elementos considerados tóxicos e, por este motivo, sua disposição final tem sido feita em aterros controlados. Este trabalho teve por objetivo a caracterização do resíduo de areia verde de fundição intemperizado e sua incorporação no concreto asfáltico usinado a quente. O resíduo foi caracterizado através da microscopia eletrônica de varredura, difração de raios X, fluorescência de raios X, analise térmica e p11 Alem disso, foram realizados os ensaios ambientais de solubilização, lixiviação e lixiviação neutra Os agregados foram caracterizados quanto ao tamanho das partículas através da analise granulométrica e com o resíduo de areia verde de fundição foi realizado o ensaio de equivalente de areia O ligante asfáltico foi caracterizado através dos ensaios de penetração, ponto de amolecimento, viscosidade e índice de suscetibilidade térmica A determinação do teor ótimo de ligante foi obtido através do Método Marshall Foram avaliadas as propriedades mecânicas de modulo de resiliência, tração estática e dano por umidade induzida Os resultados obtidos com os ensaios ambientais de solubilização e lixiviação, microscopia eletrônica de varredura, fluorescência de raios X e pH apresentaram redução nos teores de alumínio, ferro, sódio e sulfato, devido a redução no teor de material argiloso aderido a superfície dos grãos de areia O resultado do ensaio de modulo de resislência (cerca de 5400 MPa) e tração estática (cerca de 1 ,2OMPa) mostram que a incorporação do resíduo não afetou significativamente as propriedades mecânicas do concreto asfáltico. Entretanto, a redução de 43% de resistência no ensaio de dano por umidade induzida ficou acima do que especifica a norma brasileira, que determina a perda de resistência máxima de 30%.
128

Evolução temporal da resistencia mecanica em laboratorio, de misturas simulando a reciclagem de pavimento asfaltico com adição de cimento portland / Temporal evolution of mechanical resistance in laboratory, of mixtures simulating asphalt pavement recycling with portland cement additions

Gusmão, Claudia Betine 12 December 2008 (has links)
Orientador: João Virgilio Merighi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-12T12:23:13Z (GMT). No. of bitstreams: 1 Gusmao_ClaudiaBetine_M.pdf: 2591416 bytes, checksum: b106affc2585283a589b10f376f83035 (MD5) Previous issue date: 2008 / Resumo: O presente trabalho visa estudar o processo de reciclagem de pavimento asfaltico com cimento Portland, atraves da analise de metodo de reciclagem, equipamentos utilizados, procedimentos empregados em campo, alem do estudo das vantagens e desvantagens do uso da reciclagem em pavimentos asfalticos. O trabalho trata ainda de uma forma detalhada o pavimento asfaltico com adicao de cimento Portland, atraves de ensaios tecnologicos simulando em laboratorio, para diferentes dosagens o comportamento mecanico em funcao do tempo do material obtido em campo. / Abstract: This work studies the process of asphalted pavement recycling with cement Portland additive through the analysis of recycling method, equipments and procedures used in the field, in addition to studying the advantages and disadvantages of the use of recycling in asphalted pavement. The work also approaches in detail the recycled asphalt pavement with Portland cement additive, through technological tests through laboratory simulation, to different dosage and the analysis of mechanical behavior through time of that material obtained in field. / Mestrado / Transportes / Mestre em Engenharia Civil
129

Pavimentos flexíveis com revestimento asfáltico = avaliação estrutural a partir dos parâmetros de curvatura da bacia de deformação / Flexible pavements : structural evaluation based on deflection basin parameters

Lopes, Flaviane Melo 20 August 2018 (has links)
Orientador: Rita Moura Fortes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo. / Made available in DSpace on 2018-08-20T02:21:51Z (GMT). No. of bitstreams: 1 Lopes_FlavianeMelo_M.pdf: 8802487 bytes, checksum: aac710475cf4e380e179dca7eeef82be (MD5) Previous issue date: 2012 / Resumo: No Brasil é significativo o crescimento do uso do equipamento tipo Falling Weight Deflectometer - FWD para o levantamento deflectométrico e posterior caracterização estrutural de pavimentos existentes. Esta caracterização ainda é realizada somente através da medida de deflexão máxima. Contudo, o conhecimento isolado da deflexão máxima (D0) pode não ser suficientemente conclusivo para se diagnosticar a condição estrutural do pavimento. Sendo assim, o presente estudo tem como objetivo, por meio de estudo paramétrico, propor uma metodologia simplificada de avaliação da condição estrutural de pavimentos asfálticos com base granular utilizando as medições da bacia deflectométrica. A determinação de parâmetros de curvatura da bacia de deformação, obtidos através de um levantamento deflectométrico, serão utilizados para o desenvolvimento de correlações destes com as deformações críticas geradas na estrutura do pavimento quando solicitado. Através das correlações obtidas, propõem-se modelos simplificados para estimar a vida remanescente de um pavimento em função dos parâmetros deflectométricos. A metodologia proposta mostrou-se promissora. O aproveitamento das informações da bacia deflectométrica pode auxiliar na solução de restauração do pavimento, evitando defeitos precoces por falhas no diagnóstico / Abstract: In Brazil it is significant the increase in the use of an equipment type Falling Weight Deflectometer - FWD for deflection analysis and structural characterization of existing pavements. This characterization is still held only through a maximum deflection measure. However, the isolated association of maximum deflection (D0) may not be conclusive enough to diagnose the structural condition of the pavement. Thus, the current study aims, through parametric study, to propose a simplified structural assessment methodology of asphalt pavement condition with granular base using measurements of deflection basin. The determination of deflection basin parameters, obtained through deflection measurements, will be used for the development of these correlations with significant deformation of pavement structure generated when prompted. Through the correlations obtained simplified models will be proposed to estimate the remaining life of a pavement according to deflection parameters. The proposed methodology has proved to be promising. The use of the information on deflection basin can help out in troubleshooting pavement rehabilitation, avoiding premature failures in diagnosing faults / Mestrado / Transportes / Mestre em Engenharia Civil
130

Rational Approach to Evaluate Asphalt Concrete Base Course Design for Improving Construction Quality and Performance

Garcia Ruiz, Johnnatan 16 September 2022 (has links)
No description available.

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