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Avaliou-se a influencia da variacao de temperatura no comportamento mecânico de misturas asfalticas com o agregado sinterizado de argila calcinada (ASAC), o qual foi utilizado como substituto ao seixo, em razao da carencia regional de material petreo. Participaram tambem da composicao betuminosa, o ligante asfaltico CAP 50/70, comercializado no territorio amazonense; o cimento Portland CP II-Z-32, na condicao de filer; e tres tipos de areia, os quais representaram o agregado miudo, um deles oriundo da producao do ASAC e dois naturais, provenientes dos municipios de Manaus e Coari (AM). A granulometria da mistura seguiu o metodo de Bailey, com o fito de propiciar um melhor intertravamento das particulas. Examinou-se o comportamento mecânico em diferentes temperaturas, por meio dos ensaios de Resistencia a Tracao (RT), Modulo de Resili-encia (MR) e Vida de fadiga. Os resultados mostraram, em geral, desempenho superior das composicoes as-falticas com os agregados de argila, em comparacao as formulacoes com o agregado natural, dentro do inter-valo de temperatura de 25 a 60oC. Palavras-chave: agregado sinterizado de argila calcinada, misturas asfalticas, resistencia a tracao, modulo de resiliencia, vida de fadiga.

The aim of this study is to search for a substitute for the natural coarse aggregate in various regions of the world, such as Amazon-Brazil, where this type of material is lacking. The asphalt binder AC 50/70 is mixed with an aggregate obtained from the sinterization of a calcined clay (SACC) as a possible alternative to coarse aggregate material for the construction of asphalt pavements in tropical zones. The dynamic modulus |E*| of this mixture was measured under strain control mode and in tension control mode. The results are compared with those obtained from AC 50/70 mixed with pebbles, which is currently used as the coarse aggregate in this region. For pavements that work at high temperatures, such as 40℃, and low frequencies, the mixture with SACC appears to be a viable alternative to coarse aggregate material for the construction of asphalt pavements in tropical zones.

The handmade manufacture of sintered calcinated clay aggregates (ASAC, in Portuguese) is a slow process that it results in small output of material whit discontinuous gradation, fact that indeed hindered the framing of the asphalt mixtures within the granulometric limits used. This work introduces the productive process of said material made in the facilities of a ceramic manufacturer. The raw material is a typical clayey soil of the Urucu-AM oil fields. The natural material, as well as the manufactured sintered aggregates, was validated through the use of DNIT and ABNT - recommended tests. The results proved to be satisfactory having shown that said material is apt to being used in the composition of the asphalt mixture and solving the shortage of stony material in the region, besides minimizing the extraction of natural resources usually employed in the paving services in the region. Key words: sintered calcinated clay aggregates, industrial production, ceramic.

Expressivo número de municípios amazonenses se encontra localizado em áreas carentes em agregados pétreos, o que leva os construtores de pavimentos a adotarem alternativas que, em retrospecto histórico, propiciam pavimentos de deficiente resistência mecânica. Conquanto mais eficaz e apropriado do ponto de vista técnico, o concreto betuminoso usinado à quente é normalmente evitado por conta da indicada carência estadual em agregados pétreos. Em face do peculiar contexto amazonense, revela-se recomendável à circunstância em testilha a adoção de agregados sintéticos de argila calcinada (ASAC), com matéria-prima abundante (argila) no Amazonas. Trabalhos anteriores, realizados pelo Grupo de Geotecnia da Universidade Federal do Amazonas, demonstram que solos argilosos, costumeiramente empregados para produção de material cerâmico, podem produzir agregados sintéticos com adequadas propriedades mecânicas. Nesta pesquisa, amostras com características similares às desses solos foram encontradas na rodovia BR-319, que liga Manaus (AM) a Porto Velho (RO). Trata-se de estrutura, em geral, a ostentar péssimas condições de tráfego, incluída, de maneira justificável, como um dos alvos da política pública de recuperação de rodovias, conduzida pelo Ministério dos Transportes. Neste estudo, dosaram-se misturas asfálticas com agregado sintético e com seixo rolado oriundo do leito dos rios amazonenses, a fim de se comparar o desempenho mecânico de tais misturas por meio da determinação do módulo resiliente (MR). Os resultados, em regra, denotam que as misturas asfálticas confeccionadas com agregado sintético de argila calcinada, quando confrontadas com aquelas confeccionadas com o material natural (seixo), apresentaram: (a) maiores resistências à tração e aos módulos resiliente; (b) baixa tendência à deformação, assim como uma recuperação elástica considerável e (c) menor susceptibilidade às deformações permanentes. A substantial number of municipal districts in the State of Amazonas are located in areas which are poor in stony materials. And this has led pavement builders into adopting alternatives which have historically produced pavements with low mechanical strength. Whist more effective and appropriate from a technical standpoint, the asphalt concrete has been usually left aside due to the referred lack of stony materials. Because of the specific situation in the State of Amazonas the adoption of synthetic calcinated clay aggregates (SCCA), with an abundant raw material (clay) in the State of Amazonas is recommended in lieu of the traditional practice. Previous works carried out by the Federal University of Amazonas Geotechny Group have demonstrated that the clay soil commonly used in the production of ceramic materials can yield synthetic aggregates with adequate mechanical properties. In this research work, samples featuring similar characteristics as those of the soils in question have been found along the BR-319 highway connecting the Manaus (AM) city to Porto Velho (RO) city. The transportation structure in general is in deplorable conditions. Justifiably so, the recovery of this highway has been earmarked as one of the targets for the Ministry of Transportation. In this study, asphalt mixtures were blended with synthetic aggregates and pebbles taken from the river bed in order to compare the mechanical performance of such mixtures by means of the determination of the resilient modulus (RM). The results, as a rule, have shown that the asphalt mixtures comprising synthetic calcinated clay aggregates when compared with those comprising the naturally-found material (river bed pebbles) have shown: (a) greater tensile and resilient modulus strengths; (b) low deformation tendency, as well as a considerable elastic recovery and (c) less susceptibility to permanent deformation.