Made available in DSpace on 2014-12-17T15:01:34Z (GMT). No. of bitstreams: 1 JuliaCLT_DISSERT.pdf: 2162032 bytes, checksum: 7f341c00df066e306597bec708b72f71 (MD5) Previous issue date: 2013-08-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The increasing demand for asphalt leads to the development of techniques that can improve the quality of products and increase the useful working life of pavements. Consequently, there is a growing application of asphalt emulsions, which are produced from a mixture of petroleum asphalt cement (CAP) with an aqueous phase. The main advantage of asphalt emulsions is its cold application, reducing energy costs. Conventional emulsions are obtained using asphalt, water, solvent, and additives. The modified asphalt emulsion is developed by adding a modifying agent to conventional emulsions. These modifiers can be natural fibers, waste polymers, nanomaterials. In this work modified asphalt emulsion were obtained using organoclays. First, it was prepared a conventional asphalt emulsion with the following mass proportion: 50% of 50/70 penetration grade CAP, 0.6% of additives and 3% of emulsifier, 20% of solvent and 26.4% of water. It was used bentonite and vermiculite (1% and 4%) to obtain the modified asphalt emulsion. Bentonite and vermiculite were added in its raw state and as an organoclay form and as an organoclay-acid form, resulting in 26 experimental runs. The methodology described by Qian et al. (2011), with modifications, was used to obtain the organoclay and the organoclay-acid form. infrared spectroscopy (IR)) were used to characterize the clays and nanoclays. The emulsions were prepared in a colloidal mill, using 30 minutes and 1 hour as mixing time. After, the emulsions were characterized. The following tests were performed, in accordance with the Brazilian specifications (DNER- 369/97): sieve analysis, Saybolt Furol viscosity, pH determination, density, settlement and storage stability, residue by evaporation, and penetration of residue. Finally, it can be concluded that the use of nanoclays as asphalt modifiers represent a viable alternative to the road paving industry / Com o aumento da demanda por asfaltos, faz-se necess?rio o desenvolvimento de t?cnicas que melhorem a qualidade e aumentem o tempo de vida ?til dos pavimentos. Com isso, cresce a aplica??o das emuls?es asf?lticas, que s?o produzidas a partir de uma mistura de Cimento Asf?ltico de Petr?leo (CAP) e uma fase aquosa, tendo como principal vantagem a redu??o de custos energ?ticos devido a sua aplica??o ser a frio. Neste trabalho foram obtidas emuls?es asf?lticas convencionais e modificadas. Para a obten??o de emuls?es asf?lticas convencionais foram utilizados os seguintes constituintes: asfalto, ?gua, solvente e aditivos. As emuls?es asf?lticas modificadas foram desenvolvidas a partir da adi??o de um agente modificante ?s emuls?es asf?lticas convencionais. Os agentes modificantes utilizados foram a bentonita e a vermiculita natural e modificadas com tensoativos. Primeiramente, preparou-se uma emuls?o asf?ltica convencional nas seguintes propor??es: 50% de CAP 50/70, 0,6% de aditivos e 3% de emulsificante em rela??o ? quantidade de asfalto, 20% de solvente e 26,4% de ?gua. Para a obten??o da emuls?o asf?ltica modificada, foi utilizada a bentonita e vermiculita como agente modificador em propor??es de 1% e 4 %. Os constituintes foram adicionados ao moinho coloidal por per?odos de 30 e 60 minutos. Foram realizados 26 ensaios, onde a bentonita e vermiculita foram adicionadas na sua forma natural, na forma organof?lica e na forma organof?lica em meio ?cido. Para a obten??o da argila organof?lica e organof?lica em meio ?cido utilizou-se o m?todo de Qian et al. (2011), com adapta??es. Para caracteriza??o das argilas e nanoargilas utilizou-se a t?cnica de espectroscopia no infravermelho (IV). Ap?s o per?odo de emulsifica??o, foram realizados os ensaios para caracteriza??o da emuls?o obtida. Os seguintes ensaios foram realizados, de acordo com as especifica??es t?cnicas (DNER-EM 369/97): peneiramento, viscosidade Saybolt Furol, pH, densidade, sedimenta??o, res?duo por evapora??o e penetra??o. Por fim, pode-se concluir que as emuls?es asf?lticas modificadas com nanoargilas apresentam-se como uma alternativa para o setor de pavimenta??o

Made available in DSpace on 2014-12-17T15:01:55Z (GMT). No. of bitstreams: 1 CristianKML_TESE.pdf: 2781872 bytes, checksum: b802df1c9b2c68b6ef21241e1bb5281e (MD5) Previous issue date: 2012-08-03 / The main objective of this research was the development and characterization of conventional and modified cationic asphalt emulsions. The asphalt emulsions were developed by using the Petroleum Asphalt Cement (CAP 50-70) from Fazenda Bel?m (Petrobras -Aracati-Ce). The first step in this research was the development of the oil phase (asphalt + solvent) and the aqueous phase (water + emulsifying agent + acid + additives), separately. During the experiments for the obtaining of the conventional asphalt emulsion, the concentration of each constituent was evaluated. For the obtaining of the oil phase, kerosene was used as solvent at 15 and 20 wt.%. For the development of the aqueous phase, the emulsifying agent was used at 0.3 and 3.0 wt.%, whereas the acid and the additive were set at 0.3 wt.%. The percentage of asphalt in the asphalt emulsion was varied in 50, 55, and 60 wt.% and the heating temperature was set at 120 ?C. The aqueous phase in the asphalt emulsion was varied from 16.4 to 34.1 wt.% and the heating temperature was set at 60 ?C. After the obtaining of the oil and the aqueous phases, they were added at a colloidal mill, remaining under constant stirring and heating during 15 minutes. Each asphalt emulsion was evaluated considering: sieve analysis, Saybolt Furol viscosity, pH determination, settlement and storage stability, residue by evaporation, and penetration of residue. After the characterization of conventional emulsions, it was chosen the one that presented all properties in accordance with Brazilian specifications (DNER-EM 369/97). This emulsion was used for the development of all modified asphalt emulsions. Three polymeric industrial residues were used as modifier agents: one from a clothing button industry (cutouts of clothing buttons) and two from a footwear industry (cutouts of sandals and tennis shoes soles), all industries located at Rio Grande do Norte State (Brazil).The polymeric residues were added into the asphalt emulsion (1 to 6 wt.%) and the same characterization rehearsals were accomplished. After characterization, it were developed the cold-mix asphalts. It was used the Marshall mix design. For cold-mix asphalt using the conventional emulsion, it was used 5, 6 and 7 wt.% asphalt emulsion. The conventional mixtures presented stability values according Brazilian specification (DNER-369/97). For mixtures containing asphalt modified emulsions, it was observed that the best results were obtained with emulsions modified by button residue / Neste trabalho desenvolveu-se e caracterizou-se emuls?es asf?lticas cati?nicas convencionais e modificadas. As emuls?es asf?lticas convencionais foram obtidas utilizandose como mat?ria-prima o Cimento Asf?ltico de Petr?leo (CAP 50-70), oriundo da Fazenda Bel?m (PETROBRAS-Aracati-CE), cedido pela LUBNOR-Lubrificantes e Derivados de Petr?leo do Nordeste (Fortaleza-CE). A pesquisa foi iniciada com o desenvolvimento da fase ?leo (asfalto + solvente) e da fase aquosa (?gua + emulsificante + ?cido + aditivo), separadamente. Para a obten??o da emuls?o asf?ltica convencional, a concentra??o de cada constituinte foi avaliada. Para a fase ?leo, o asfalto foi utilizado nas concentra??es de 50, 55 e 60 %, e o solvente (querosene) nas concentra??es de 15 e 20 %. A temperatura de aquecimento desta fase foi de 120 ?C. Para o desenvolvimento da fase aquosa, o emulsificante foi utilizado nas concentra??es de 0,3 e 3,0 %, enquanto que o ?cido e o aditivo foram utilizados apenas na concentra??o de 0,3 %. A concentra??o de ?gua variou de 16,4 a 34,1 % e a temperatura de aquecimento da fase aquosa foi de 60 ?C. Ap?s o preparo de ambas as fases, estas foram introduzidas no moinho coloidal, onde permaneceram em aquecimento e em sistema de refluxo, durante 15 minutos. Ap?s a obten??o de cada emuls?o asf?ltica, foram feitos os seguintes ensaios de caracteriza??o: peneiramento, viscosidade Saybolt Furol, pH, sedimenta??o, adesividade, res?duo por evapora??o e penetra??o. Ap?s a caracteriza??o das emuls?es asf?lticas convencionais, escolheu-se a emuls?o que apresentou resultados de acordo com a especifica??o (DNER-EM 369/97) para, em seguida, desenvolver as emuls?es asf?lticas modificadas. As emuls?es asf?lticas foram modificadas atrav?s da adi??o de res?duos polim?ricos provenientes da ind?stria de bot?es e de cal?ados (sand?lia e t?nis), localizadas no Rio Grande do Norte. Os res?duos polim?ricos foram adicionados na emuls?o asf?ltica de 1 a 6 %. Ap?s a obten??o das emuls?es asf?lticas modificadas foram feitos os ensaios de caracteriza??o. Conclu?da tais etapas, continuou-se a pesquisa com o desenvolvimento de misturas asf?lticas a frio. O m?todo Marshall foi utilizado como m?todo de dosagem destas misturas. De acordo com os resultados obtidos, conclui-se que foi poss?vel determinar uma composi??o de emuls?o asf?ltica convencional que atendesse a alguns requisitos presentes na especifica??o (DNER-EM 369/97). Quanto ?s misturas asf?lticas a frio, utilizando as emuls?es convencionais, conclui-se que, para os teores de emuls?o utilizados (5, 6 e 7 %), estas apresentaram valores de estabilidade acima do recomendado na especifica??o. Para as misturas asf?lticas a frio, que utilizaram as emuls?es modificadas, os melhores resultados de estabilidade foram obtidos com a emuls?o modificada com res?duo de bot?o