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QUALITY AND DURABILITY OF RUBBERIZED ASPHALT CEMENT AND WARM RUBBERIZED ASPHALT CEMENTADHIKARI, THAM 25 April 2013 (has links)
This thesis discusses and documents findings from an investigation of performance-based testing of asphalt cement (AC), warm mixed asphalt cement, asphalt rubber (AR), and warm asphalt rubber. A number of control, warm, and asphalt rubber binders from Ontario construction contracts were investigated for their compliance with conventional Superpave® test methods such as rolling thin film (RTFO), pressure aging vessel (PAV), dynamic shear rheometer (DSR), and bending beam rheometer (BBR), as well as additional specification tests such as extended BBR and double edge notched tension test. The quality and durability of those binders were determined. Quality means the ability of asphalt binder to reach a set of specific properties whereas durability is the measure of how well asphalt retains its original characteristics when exposed to normal weathering and aging process.
One warm AC and two field-blended asphalt rubber samples showed high levels of physical hardening which can lead to premature and early cracking. The warm asphalt cement lost 8 °C when stored isothermally for three days at low temperatures according to Ontario’s extended bending beam rheometer (BBR) protocol (LS-308). The two asphalt rubber samples lost 10 °C and 12 °C following the same conditioning. Many of the studied asphalt samples showed deficient strain tolerance as measured in Ontario’s double-edge-notched tension (DENT) test (LS-299).
In a study of warm rubberized asphalt cement with improved properties, a number of compositions were prepared with soft Cold Lake AC and a small quantity of naphthenic oil. These binders showed little chemical and physical hardening and reasonable critical crack tip opening displacements (CTOD). Strain tolerance was much improved by co-blending with a high vinyl type styrene-butadiene-styrene (SBS) polymer and a small amount of sulfur. / Thesis (Master, Chemistry) -- Queen's University, 2013-04-24 22:54:20.07
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Caracterização à fadiga de ligantes asfálticos modificados envelhecidos a curto e longo prazo / Fatigue characterization of short-term and long-term aged modified asphalt binders.Nuñez, Javier Yesid Mahecha 23 August 2013 (has links)
O trincamento por fadiga é um dos principais mecanismos de deterioração dos pavimentos flexíveis e, mesmo assim, é, ainda hoje, um dos defeitos mais difíceis de serem controlados. Uma das alternativas para a melhoria das características de fadiga das misturas asfálticas é o emprego de ligantes asfálticos modificados, porém, há dúvida se o enrijecimento provocado pela adição dos modificadores pode influenciar a resistência à fadiga da mistura asfáltica. Com o intuito de mensurar características do ligante asfáltico que tenham relação com o trincamento por fadiga da mistura asfáltica, alguns ensaios de laboratório foram desenvolvidos recentemente, destacando-se dois: o ensaio de varredura de tempo (time sweep) e o ensaio de varredura de amplitude linear (LAS). O objetivo deste trabalho é caracterizar o comportamento à fadiga de 12 ligantes asfálticos modificados de mesmo grau de desempenho (PG 76-xx). As formulações CAP+PPA, CAP+SBS, CAP+SBS+PPA, CAP+Borracha, CAP+Borracha+PPA, CAP+PE, CAP+PE+PPA, CAP+EVA, CAP+EVA+PPA, CAP+SBR, CAP+SBR+PPA e CAP+Elvaloy+PPA foram preparadas tendo como base um ligante asfáltico 50/70 de classificação PG 64-xx. Com base na caracterização realizada neste estudo, as principais conclusões são: (a) o material que apresentou melhor vida de fadiga foi o CAP+EVA; (b) o material menos sensível à deformação foi o CAP puro; (c) o menos sensível à temperatura foi o CAP+PPA; (d) o efeito do PPA nos ligantes asfálticos com outros aditivos provocou diminuição da vida de fadiga para a maioria das formulações, aumento da sensibilidade aos níveis de deformação para todas as formulações, diminuição da sensibilidade à temperatura e aumento da sensibilidade ao envelhecimento para a maioria das formulações; (e) tomando por base o ordenamento final das melhores características à fadiga dos ligantes asfálticos segundo os parâmetros analisados, o CAP+Borracha apresenta o melhor desempenho global / Fatigue cracking is a major mechanism of deterioration of flexible pavements, and even then, it is still one of the defects that are more difficult to control. One alternative to improve fatigue characteristics of asphalt mixtures is the use of modified asphalt binders; however, there is no doubt that the stiffening caused by the addition of modifiers can influence the fatigue resistance of asphalt mixture. In order to measure characteristics of asphalt binders that are related to the fatigue cracking of asphalt mixture, some laboratory tests have been recently developed such as the time sweep and the linear amplitude sweep (LAS) test. The objective of this study is to characterize the fatigue behavior of 12 modified asphalt binders with the same high-temperature performance grade (PG 76-xx). The formulations AC+PPA, AC+SBS, AC+SBS+PPA, AC+Rubber, AC+Rubber+PPA, AC+PE, AC+PE+PPA, AC+EVA, AC+EVA+PPA, AC+SBR, AC+SBR+PPA and AC+Elvaloy+PPA were prepared with a 50/70 base asphalt binder graded as PG 64-xx in the Superpave specification. Based on the characterization made in this study, the main conclusions are the following: (a) the material that showed better fatigue life was the AC+EVA; (b) the material that is less sensitive to deformation was the neat AC; (c) the less sensitive one to temperature was the AC+PPA; (d) the effect of PPA in asphalt binders prepared with other additives caused a reduction in the fatigue life for many formulations, an increase in the sensitivity levels of deformation for all formulations, a reduction in the sensitivity to temperature and an increase in the sensitivity to aging for several formulations; (e) on the final ranking of the characteristics of asphalt binders according to the parameters analyzed in this research study, the AC+Rubber showed the best overall performance
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Caracterização à fadiga de ligantes asfálticos modificados envelhecidos a curto e longo prazo / Fatigue characterization of short-term and long-term aged modified asphalt binders.Javier Yesid Mahecha Nuñez 23 August 2013 (has links)
O trincamento por fadiga é um dos principais mecanismos de deterioração dos pavimentos flexíveis e, mesmo assim, é, ainda hoje, um dos defeitos mais difíceis de serem controlados. Uma das alternativas para a melhoria das características de fadiga das misturas asfálticas é o emprego de ligantes asfálticos modificados, porém, há dúvida se o enrijecimento provocado pela adição dos modificadores pode influenciar a resistência à fadiga da mistura asfáltica. Com o intuito de mensurar características do ligante asfáltico que tenham relação com o trincamento por fadiga da mistura asfáltica, alguns ensaios de laboratório foram desenvolvidos recentemente, destacando-se dois: o ensaio de varredura de tempo (time sweep) e o ensaio de varredura de amplitude linear (LAS). O objetivo deste trabalho é caracterizar o comportamento à fadiga de 12 ligantes asfálticos modificados de mesmo grau de desempenho (PG 76-xx). As formulações CAP+PPA, CAP+SBS, CAP+SBS+PPA, CAP+Borracha, CAP+Borracha+PPA, CAP+PE, CAP+PE+PPA, CAP+EVA, CAP+EVA+PPA, CAP+SBR, CAP+SBR+PPA e CAP+Elvaloy+PPA foram preparadas tendo como base um ligante asfáltico 50/70 de classificação PG 64-xx. Com base na caracterização realizada neste estudo, as principais conclusões são: (a) o material que apresentou melhor vida de fadiga foi o CAP+EVA; (b) o material menos sensível à deformação foi o CAP puro; (c) o menos sensível à temperatura foi o CAP+PPA; (d) o efeito do PPA nos ligantes asfálticos com outros aditivos provocou diminuição da vida de fadiga para a maioria das formulações, aumento da sensibilidade aos níveis de deformação para todas as formulações, diminuição da sensibilidade à temperatura e aumento da sensibilidade ao envelhecimento para a maioria das formulações; (e) tomando por base o ordenamento final das melhores características à fadiga dos ligantes asfálticos segundo os parâmetros analisados, o CAP+Borracha apresenta o melhor desempenho global / Fatigue cracking is a major mechanism of deterioration of flexible pavements, and even then, it is still one of the defects that are more difficult to control. One alternative to improve fatigue characteristics of asphalt mixtures is the use of modified asphalt binders; however, there is no doubt that the stiffening caused by the addition of modifiers can influence the fatigue resistance of asphalt mixture. In order to measure characteristics of asphalt binders that are related to the fatigue cracking of asphalt mixture, some laboratory tests have been recently developed such as the time sweep and the linear amplitude sweep (LAS) test. The objective of this study is to characterize the fatigue behavior of 12 modified asphalt binders with the same high-temperature performance grade (PG 76-xx). The formulations AC+PPA, AC+SBS, AC+SBS+PPA, AC+Rubber, AC+Rubber+PPA, AC+PE, AC+PE+PPA, AC+EVA, AC+EVA+PPA, AC+SBR, AC+SBR+PPA and AC+Elvaloy+PPA were prepared with a 50/70 base asphalt binder graded as PG 64-xx in the Superpave specification. Based on the characterization made in this study, the main conclusions are the following: (a) the material that showed better fatigue life was the AC+EVA; (b) the material that is less sensitive to deformation was the neat AC; (c) the less sensitive one to temperature was the AC+PPA; (d) the effect of PPA in asphalt binders prepared with other additives caused a reduction in the fatigue life for many formulations, an increase in the sensitivity levels of deformation for all formulations, a reduction in the sensitivity to temperature and an increase in the sensitivity to aging for several formulations; (e) on the final ranking of the characteristics of asphalt binders according to the parameters analyzed in this research study, the AC+Rubber showed the best overall performance
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Posouzení nízkohlučného asfaltového koberce mastixového s CRmB / Evaluation of Low Noise Stone Mastix Asphallt with CRmBZavřel, Tomáš January 2012 (has links)
The aim of diploma thesis is to design mixture SMA LA 8 with crumb rubber modified bitumen (9,9 %) and a modifier additive TecRoad (22 %) and the test of water sensitivity, the resistance to permanent deformation and to frost cracking, the determination of the stiffness and fatigue characteristics. Test methods are described and evaluated.
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Odolnost asfaltových pojiv proti stárnutí / Resistance of bituminous binder to ageingRous, Vojtěch January 2013 (has links)
Asphalt binder ageing and experiences with various ageing methods from abroad are described in this thesis. The practical part deals with the RTFOT aging and with the influence of the duration of this test. The comparison of test results is conducted before and after the aging by values of needle penetration, elastic recovery, softening point and resilience tests are evaluated and compared.
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Caracterização do comportamento fluência-recuperação de ligantes asfálticos modificados virgens e envelhecidos / Characterization of the creep-recovery behavior of unaged and short-term aged modified asphalt bindersDomingos, Matheus David Inocente 13 December 2011 (has links)
O ensaio de fluência e recuperação sob tensão múltipla (MSCR) é resultado do aperfeiçoamento do ensaio de fluência repetida e recuperação (RCRT) pela Administração Rodoviária Federal dos Estados Unidos (FHWA) e tem por objetivo avaliar o percentual de recuperação, a compliância não-recuperável e a dependência dos ligantes asfálticos, especialmente os modificados, quanto ao nível de tensão. O MSCR foi utilizado neste estudo para caracterizar o comportamento fluência-recuperação de diversos ligantes asfálticos modificados virgens e envelhecidos a curto prazo. Foi empregado o procedimento da norma ASTM D7405, que prescreve os tempos de fluência e recuperação de 1 e 9 s, e avaliada a influência do aumento dos tempos de fluência e recuperação de 1 e 9 s para 2 e 18 s nas propriedades dos ligantes asfálticos envelhecidos a curto prazo. Além dos resultados destes ensaios, foram utilizados os valores de penetração, ponto de amolecimento, viscosidade rotacional, penetração retida, incremento do ponto de amolecimento, incremento de viscosidade e perda de massa para verificar quais ligantes asfálticos apresentam melhor comportamento à luz das propriedades e parâmetros considerados. Foram preparados doze materiais modificados e de classificação PG 76-XX tendo como base um CAP 50/70 de classificação PG 64-XX: CAP+PPA, CAP+Elvaloy+PPA, CAP+borracha, CAP+borracha+PPA, CAP+SBS, CAP+SBS+PPA, CAP+EVA, CAP+EVA+PPA, CAP+PE, CAP+PE+PPA, CAP+SBR e CAP+SBR+PPA. O CAP+Elvaloy+PPA apresenta, em um contexto geral, o melhor desempenho nas propriedades e parâmetros analisados em virtude dos bons resultados do percentual de recuperação e da compliância não-recuperável e das menores sensibilidades à tensão. O CAP+PE apresenta o pior desempenho geral dentre os materiais estudados, na medida em que os resultados do percentual de recuperação e da compliância não-recuperável deste ligante asfáltico são ruins e as sensibilidades ao aumento nos tempos de fluência e recuperação de 1 e 9 s para 2 e 18 s são elevadas. Ao ordenar os ligantes asfálticos do melhor para o pior à luz das propriedades e parâmetros considerados, o resultado é: CAP+Elvaloy+PPA, CAP+EVA, CAP+EVA+PPA, CAP+PPA, CAP+borracha+PPA, CAP+SBR+PPA, CAP+SBS+PPA, CAP+SBS, CAP+PE+PPA, CAP+borracha, CAP+SBR, CAP 50/70 e CAP+PE. / The multiple stress creep and recovery (MSCR) test is the result of a refinement of the repeated creep and recovery test (RCRT). This refinement was performed by the United States Federal Highway Administration (FHWA) with the aim of evaluating the percent recovery, the non-recoverable compliance and the stress dependency of asphalt binders, especially the modified ones. The MSCR test was applied in this study in order to characterize the creep-recovery behavior of unaged and short-term aged modified asphalt binders. The test procedure prescribed in ASTM D7405 specification was adopted and, to evaluate the influence of a greater creep-recovery time in the behavior of asphalt binders, the creep and recovery times of 2 and 18 s were also adopted in additional tests. The results of these tests, as well as the penetration, softening point, rotational viscosity, retained penetration, softening point increase, viscosity increase and mass loss data and mixing and compaction temperatures, were used with the objectives of ranking the asphalt binders and checking the ones with the best results in the parameters and properties considered. By using a PG 64-XX base asphalt-binder of 50/70 penetration grade, the following PG 76-XX odified asphalt binders were prepared: AC+PPA, AC+Elvaloy+PPA, AC+crumb rubber, AC+crumb rubber+PPA, AC+SBS, AC+SBS+PPA, AC+EVA, AC+EVA+PPA, AC+PE, AC+PE+PPA, AC+SBR and AC+SBR+PPA. In general, AC+Elvaloy+PPA has the best results in the parameters and properties considered in this study, especially due to the good results in the percent recovery and non-recoverable compliance and the lower stress sensitivity. In general, AC+PE has the worst results among the asphalt binders considered in this work, due to the facts that the percent recovery and non-recoverable compliance results are not good and the sensitivities to the creep-recovery times are high. By taking the results of this study and ranking the asphalt binders from the best to the worst, the following sequence is obtained: AC+Elvaloy+PPA, AC+EVA, AC+EVA+PPA, AC+PPA, AC+crumb rubber+PPA, AC+SBR+PPA, AC+SBS+PPA, AC+SBS, AC+PE+PPA, AC+crumb rubber, AC+SBR, neat AC and AC+PE.
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Caracterização do comportamento fluência-recuperação de ligantes asfálticos modificados virgens e envelhecidos / Characterization of the creep-recovery behavior of unaged and short-term aged modified asphalt bindersMatheus David Inocente Domingos 13 December 2011 (has links)
O ensaio de fluência e recuperação sob tensão múltipla (MSCR) é resultado do aperfeiçoamento do ensaio de fluência repetida e recuperação (RCRT) pela Administração Rodoviária Federal dos Estados Unidos (FHWA) e tem por objetivo avaliar o percentual de recuperação, a compliância não-recuperável e a dependência dos ligantes asfálticos, especialmente os modificados, quanto ao nível de tensão. O MSCR foi utilizado neste estudo para caracterizar o comportamento fluência-recuperação de diversos ligantes asfálticos modificados virgens e envelhecidos a curto prazo. Foi empregado o procedimento da norma ASTM D7405, que prescreve os tempos de fluência e recuperação de 1 e 9 s, e avaliada a influência do aumento dos tempos de fluência e recuperação de 1 e 9 s para 2 e 18 s nas propriedades dos ligantes asfálticos envelhecidos a curto prazo. Além dos resultados destes ensaios, foram utilizados os valores de penetração, ponto de amolecimento, viscosidade rotacional, penetração retida, incremento do ponto de amolecimento, incremento de viscosidade e perda de massa para verificar quais ligantes asfálticos apresentam melhor comportamento à luz das propriedades e parâmetros considerados. Foram preparados doze materiais modificados e de classificação PG 76-XX tendo como base um CAP 50/70 de classificação PG 64-XX: CAP+PPA, CAP+Elvaloy+PPA, CAP+borracha, CAP+borracha+PPA, CAP+SBS, CAP+SBS+PPA, CAP+EVA, CAP+EVA+PPA, CAP+PE, CAP+PE+PPA, CAP+SBR e CAP+SBR+PPA. O CAP+Elvaloy+PPA apresenta, em um contexto geral, o melhor desempenho nas propriedades e parâmetros analisados em virtude dos bons resultados do percentual de recuperação e da compliância não-recuperável e das menores sensibilidades à tensão. O CAP+PE apresenta o pior desempenho geral dentre os materiais estudados, na medida em que os resultados do percentual de recuperação e da compliância não-recuperável deste ligante asfáltico são ruins e as sensibilidades ao aumento nos tempos de fluência e recuperação de 1 e 9 s para 2 e 18 s são elevadas. Ao ordenar os ligantes asfálticos do melhor para o pior à luz das propriedades e parâmetros considerados, o resultado é: CAP+Elvaloy+PPA, CAP+EVA, CAP+EVA+PPA, CAP+PPA, CAP+borracha+PPA, CAP+SBR+PPA, CAP+SBS+PPA, CAP+SBS, CAP+PE+PPA, CAP+borracha, CAP+SBR, CAP 50/70 e CAP+PE. / The multiple stress creep and recovery (MSCR) test is the result of a refinement of the repeated creep and recovery test (RCRT). This refinement was performed by the United States Federal Highway Administration (FHWA) with the aim of evaluating the percent recovery, the non-recoverable compliance and the stress dependency of asphalt binders, especially the modified ones. The MSCR test was applied in this study in order to characterize the creep-recovery behavior of unaged and short-term aged modified asphalt binders. The test procedure prescribed in ASTM D7405 specification was adopted and, to evaluate the influence of a greater creep-recovery time in the behavior of asphalt binders, the creep and recovery times of 2 and 18 s were also adopted in additional tests. The results of these tests, as well as the penetration, softening point, rotational viscosity, retained penetration, softening point increase, viscosity increase and mass loss data and mixing and compaction temperatures, were used with the objectives of ranking the asphalt binders and checking the ones with the best results in the parameters and properties considered. By using a PG 64-XX base asphalt-binder of 50/70 penetration grade, the following PG 76-XX odified asphalt binders were prepared: AC+PPA, AC+Elvaloy+PPA, AC+crumb rubber, AC+crumb rubber+PPA, AC+SBS, AC+SBS+PPA, AC+EVA, AC+EVA+PPA, AC+PE, AC+PE+PPA, AC+SBR and AC+SBR+PPA. In general, AC+Elvaloy+PPA has the best results in the parameters and properties considered in this study, especially due to the good results in the percent recovery and non-recoverable compliance and the lower stress sensitivity. In general, AC+PE has the worst results among the asphalt binders considered in this work, due to the facts that the percent recovery and non-recoverable compliance results are not good and the sensitivities to the creep-recovery times are high. By taking the results of this study and ranking the asphalt binders from the best to the worst, the following sequence is obtained: AC+Elvaloy+PPA, AC+EVA, AC+EVA+PPA, AC+PPA, AC+crumb rubber+PPA, AC+SBR+PPA, AC+SBS+PPA, AC+SBS, AC+PE+PPA, AC+crumb rubber, AC+SBR, neat AC and AC+PE.
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Uplatnění pryžového granulátu v asfaltových pojivech a hutněných asfaltových směsích / Application of crumb rubber in bituminous binders and in bituminous mixturesDašek, Ondřej Unknown Date (has links)
Presented dissertation thesis is focused on the possibility of using the crumb rubber from waste tires for modification of paving grade bitumen. The resulting asphalt rubber can be used as an alternative to polymer modified bitumen in compacted bituminous mixtures. The theoretical part describes the rheological properties of asphalt binders and the history and today state of the art in the world and in the Czech Republic. The practical part of the work contains a description of the properties of chosen crumb rubbers and produced asphalt rubbers focused on their rheological properties and on change of these properties caused by the aging at high temperature. Subsequently, the chosen empirical and functional properties of bituminous mixtures with asphalt rubber are described. Laboratory properties of these mixtures were verified under real service conditions on 32 test sections. Based on the dissertation thesis results the preliminary technical specification of the Ministry of Transport (TP 148) and their following revision were approved. The conclusion of the work summarizes and highlights the results of the dissertation.
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Rubber tyre and plastic waste use in asphalt concrete pavementOnyango, Felix Odhiambo 12 1900 (has links)
M. Tech. (Civil Engineering, Faculty of Engineering and Technology), Vaal University of Technology) / Modified asphalt concrete is one of the important construction materials for flexible pavements. The addition of polymers and natural hydrocarbon modifiers to enhance the properties of asphalt concrete over a wide temperature range in paving applications has been the common practice. Currently these modified asphalt mixtures are relatively expensive. However, recycled polymers and rubber added to asphalt have also shown similar results in improving the performance of road pavements.
In this study, an attempt has been made to use low density polyethylene (LDPE) obtained from plastic waste and crumb rubber obtained from worn out vehicle tyres. The aim was to optimise the proportions of LDPE in the bitumen binder using the ‘wet process’ and crumb rubber aggregates in the hot mix asphalt (HMA) using the ‘dry process’. The Marshall method of bituminous mix design was carried out for varying percentages of LDPE namely 2%, 4%, 6%, 8% and 10% by weight of bitumen binder and 1%, 2%, 3%, 4% and 5% crumb rubber by volume of the mineral aggregates. The characteristics of bitumen modified with LDPE were evaluated. The modified asphalt mix was also evaluated to determine the different mix characteristics.
The results from laboratory studies in terms of the rheological properties of the LDPE modified bitumen binder showed an increase in viscosity, softening point and stiffness of the binder. The optimum Marshall stability values for HMA mixtures containing 2% crumb rubber tyre and 4% LDPE were found to be 30% higher than the conventional asphalt concrete mix. The wheel tracking test done at 50ºC was 9.81mm rut depth showing a good rutting resistance of the optimized mixture compared to the conventional asphalt mixes. The Modified Lottman test gave a Tensile Strength Ratio value of 0.979 which indicates a low degree of moisture susceptibility of the modified asphalt mix. The above results showed improved properties of the asphalt mixture. The economic assessment done using the present worth of costs indicated a reduction in maintenance cost due to the extended service life of the modified asphalt pavement.
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Análise dos efeitos da borracha moída de pneu e do resíduo de óleo de xisto sobre algumas propriedades mecânicas de misturas asfáticas densas / Analysis of the effects of crumb rubber and shale-oil residue on mechanical properties of asphalt mixturesPilati, Fernanda 27 March 2008 (has links)
No Brasil, desde o início da década de 1990, vêm sendo desenvolvidas pesquisas sobre aplicação do asfalto-borracha visando tanto a diminuição dos problemas ambientais gerados pelo descarte de pneus inservíveis, como a melhoria das características dos ligantes produzidos. Dentro desse contexto, esta pesquisa teve por objetivo avaliar o desempenho mecânico de oito misturas asfálticas do tipo concreto asfáltico usinado a quente, produzidas com asfaltos convencional e convencional modificado com borracha de pneu e resíduo de óleo de xisto. Quanto ao ligante, foram utilizados 8 tipos, a saber: CAP 30/45 (referência); dois ligantes empregando teores diferentes de borracha moída de pneu; outros dois com teores distintos de resíduo de óleo de xisto e, por fim, mais três com combinações de teores de borracha e de resíduo de óleo de xisto. Os corpos-de-prova empregados nos ensaios foram moldados em cinco teores diferentes de ligantes asfálticos (4,5; 5,0, 5,5; 6,0 e 6,5%). Conseqüentemente, foram realizados ensaios Marshall, resistência à tração, módulo de resiliência e umidade induzida. Com base nos resultados dos ensaios realizados observou-se que tanto a borracha quanto o óleo reduzem a resistência à tração e o módulo de resiliência das misturas, no entanto, na recuperação retardada, os efeitos da borracha e do óleo são antagônicos, diminuindo e aumentando, respectivamente. Ademais, quanto à suscetibilidade à ação da água, as misturas com adição de óleo apresentaram menor suscetibilidade que as misturas com adição de borracha. Além disso, foi observado que todas as misturas estudadas, exceto aquelas com altas concentrações de óleo e de borracha, atenderam os requisitos estabelecidos pelas especificações, para as propriedades analisadas. Todavia, em alguns casos, considerando os efeitos antagônicos do óleo e da borracha, algumas combinações entre ambos podem ser realizadas, com a finalidade de alcançar os níveis desejados para as propriedades do ligante asfalto-borracha e das misturas asfálticas. / In Brazil, since the beginning of the 90\'s, have been developed researches on the application of asphalt-rubber seeking the reduction of environmental problems created by the used tires, and the improvement of the characteristics of the produced binder. Taking this into account, the purpose of this research is to evaluate the mechanical performance of eight hot mix asphalt concretes, produced with conventional asphalt and modified asphalt with crumb rubber and shale-oil residue. Eight types of binders were used: CAP 30/45 (reference); two binders using different crumb rubber contents, two with different shale-oil residue contents, and finally three more with the combination of crumb rubber and shale-oil residue contents. The specimens used in the laboratorial tests were compacted in five different binders contents (4.5; 5.0, 5.5; 6.0 e 6.5%). Hence, the tests performed are: Marshall test, indirect tension, resilient modulus and moisture induced. The results showed that the rubber and the shale oil reduce the indirect tension and resilience module of the mixtures, however, on the delayed recover, the effects of the rubber and of the shale oil are opposed, decreasing and increasing it, respectively. Moreover, for the moisture susceptibility, the mixtures with shale-oil residue exhibited less susceptibility to water than those with crumb rubber. Furthermore, all the studied mixtures, except those with high shale-oil residue and rubber concentrations, they got to attend the established requirements for the specifications, for the analyzed properties. Although, in some cases, considering the opposed effects of the shale oil and of the crumb rubber, some combinations between both can be accomplished, with the purpose of reach the levels wanted for the properties of the asphaltrubber binder and the asphalt mixtures. Also regression models were elaborated as for the analyzed properties. The results obtained of modeling were satisfactory.
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