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Relevant mechanical parameters of asphalt composites, such as the dynamic modulus and phase angle, are obtained by means of four-point bending tests. It is a dynamic test based on the application of sinusoidal load pulses and sinusoidal displacement response. A sinusoidal response can be difficult to record due to different issues, such as noise during an experiment. In strain-controlled tests with the application of a low-load amplitude with asphalt mixtures at high temperatures composed with calcined clay, which is the case of the test carried out in this study, a relationship was observed between the apparent noise recorded and the frequencies of the beam’s natural vibration. This outcome led to the conclusion that these imperfections are not a result of failures in the procedure, but of the natural behavior of the beam. This conclusion can assist in the filtering of information to obtain better results.

The lack of stone material in the State of Amazonas and the possibility of using solid waste in the sublayers of pavements motivates the work in question, notably with the purpose of contributing as an alternative technical solution to the paving of the city of Iranduba / AM / BR. Compositions of soil mixed with waste from milled material (MM) and construction and demolition (CDW) were studied. The materials participating in the formulations were physically characterized, as well as the mechanical behavior of the natural soil (NS) and mixtures of soil-20% milled material (NS + 20MM) and soil-20% construction and demolition waste were determined. (NS + 20CDW). The results showed that the compositions with the participation of the milled material were the most efficient relative to the mixtures with the presence of the construction and demolition residue. It is noteworthy that both formulations, referring to natural soil, improved the expansion and presented an increase in the California Bearing Ratio, selection parameters for application in the base and subfloor layers.

The asphalt coating is the layer responsible for resisting the traffic stresses of a highway. However, the search for new materials to mitigate environmental impacts and improve pavement quality is increasing. Thus, the mechanical behavior of asphalt mixtures was analyzed through the four-point bending test after the molding process and aged, with the participation of residues in the form of charcoal. The frequencies of 1Hz, 3Hz, 5Hz, 10Hz, 20Hz and 1Hz are considered at temperatures of 25°C and 40°C. The aging process contributed to improve the mechanical characteristics of the charcoal mixture at a temperature of 25 ° C, considering that there was an increase in stiffness at frequencies from 1 to 20 Hz, as well as a reduction in phase angle at frequencies of 3 Hz. , 5 Hz, 10 Hz and 20 Hz.

In this work, a model for the dynamical four-point bending test is present, with particular emphasis on application to an asphalt concrete (AC) composite, a viscoelastic material, based on the Euler-Bernoulli theory, which approaches an equation where the Young modulus E can be substituted by the operator (E + γ∂/∂t), where γ is an internal damping parameter associated to the binder viscoelasticity and t is the time. As course aggregate in the composition of the AC mixture, the sintered aggregate of calcined clay was used, interesting to be employed as an alternative to the lack of natural course aggregate in some regions of the planet, where the presence of sedimentary rocks prevails. The results indicated that γ decreases with the temperature and loading frequency and the apparent noise in the stiffness versus strain curve is resulted from the natural vibration mode of the beam.

The SMA mixtures are characterized by a high void ratio, which favors binder draindown. In order to avoid this effect, fibers are added to the mixture, which in this case came from Curauá da Amazônia (Ananas erectifolius). The final composition studied resulted in 75% coarse aggregate, 15% fine aggregate, 10% filler, 0.3% of the Curauá fiber residue, and CAP contents equal to 6.50% and 6.88% for the formulations with SMA-Crushed Stone (reference) and SMA-construction and demolition waste (alternative), respectively. The results showed for the Tensile Strength that the composites with CDW reached higher results. The Resilient Modulus values presented small variations for the set of compositions in all loading levels at a temperature of 25°C. However, at a temperature of 40°C, the aforementioned parameter presented decreases in both researched formulations. In general, at all levels examined, higher results were observed for the alternative mixture (SMA-CDW). It is noteworthy the highest results of this parameter when comparing the compositions with the Curauá fiber residue and the formulations mentioned in the literature, with the presence of other types of fibers. Regarding the increase in temperature, there was a decrease in results for both mechanical parameters (TS, DM), but with lower losses for the SMA-RCD composition. Las mezclas SMA se distinguen por el alto contenido de vacíos, favoreciendo la escorrentía del ligante asfáltico. Para evitar este efecto, se añaden fibras que, en este caso, procedían de la Curauá da Amazánia (Ananas erectifolius). La composición final estudiada dio como resultado un 75% de áridos gruesos, el 15% del árido fino, el 10% del filler mineral, el 0,3% del residuo de fibra curauá y el contenido de la Cemento Asfaltico de Petróleo (CAP) igual al 6,50% y al 6,88% para las formulaciones SMA-Grava (referencia) y SMA-RCD (alternativa), respectivamente. Los resultados mostraron que la resistencia a la tracción (RT) de los compuestos con RCD obtuvo valores más altos. Específica del Módulo de Resiliencia (MR), a una temperatura de 25°C, se verificó para todas las composiciones y, en todos los niveles de carga, valores con pequeñas variaciones. Sin embargo, a 40°C, el parámetro antes mencionado mostró disminuciones en las dos formulaciones estudiadas. En general, en todos los niveles examinados, se observaron valores más altos para la MR de la mezcla alternativa (SMA-RCD). Los resultados más altos de este parámetro destacan al comparar las composiciones con el residuo de fibra curauá y las formulaciones citadas en la literatura, con la presencia de otros tipos de fibras. En cuanto al aumento de temperatura, se verificaron disminuciones en los resultados para ambos parámetros mecánicos (RT y MR), pero con pérdidas más bajas para la composición SMA-RCD. As misturas SMA se distinguem pelo alto teor de vazios, favorecendo o escorrimento do ligante asfáltico. Para evitar tal efeito, adicionam-se fibras que, nesse caso, foram procedentes do Curauá da Amazônia (Ananas erectifolius). A composição final estudada resultou em 75% de agregado graúdo, 15% de agregado miúdo, 10% de fíler, 0,3% do resíduo da fibra do Curauá, e os teores de CAP iguais a 6.50% e 6.88% para as formulações SMA-Brita (referência) e SMA-RCD (alternativas), respectivamente. Os resultados mostraram que a Resistência à Tração para os compósitos com RCD obtiveram maiores valores. Específico ao MR, na temperatura de 25°C, verificou-se para o conjunto das composições e, em todos os níveis de carregamentos, valores com ínfimas variações. Todavia, na temperatura de 40°C, o citado parâmetro mostrou decréscimos nas duas formulações pesquisadas. No geral, em todos os níveis examinados, observou-se maiores valores para o MR da mistura alternativa (SMA-RCD). Destacam-se os resultados mais elevados desse parâmetro quando comparam-se as composições com o resíduo da fibra de Curauá e as formulações citadas na literatura, tendo a presença de outros tipos de fibras. A respeito do aumento da temperatura, comprovou-se decréscimos dos resultados para ambos os parâmetros mecânicos (RT e MR), mas com menores perdas para a composição SMA-RCD.

Devido ao alto custo da pedra britada em Manaus, as obras de pavimentacao sao executadas, em geral, com misturas asfalticas do tipo areia asfalto e com material argiloso na camada de base, o que tem resultado no aparecimento de diferentes patologias nas vias urbanas da cidade. Este estudo aponta alternativas para a pavimentacao manauara por meio da utilizacao de residuos industriais. Utilizou-se um revestimento com areia de Residuo de Construcao e Demolicao (RCD) e Cimento Asfaltico de Petroleo (CAP), modificado pelo polimero estireno e butadieno (SBS). Particularmente, comparou-se o comportamento mecânico das misturas frente ao composito usual (areia residual e CAP 50/70 puro), por meio dos ensaios de Resistencia a Tracao (RT) e Modulo de Resiliencia (MR). Adicionalmente, para contribuir com a solucao de problemas relacionados as subcamadas, acrescentou-se, ao solo argiloso, a cal de carbureto (subproduto da fabricacao do gas acetileno) e analisou-se seu desempenho pela Resistencia a Compressao Simples (RCS). Os resultados mostraram que, para a mistura asfaltica, a inclusao do polimero SBS aumentou a RT, enquanto a areia de RCD proporcionou valores mais elevados, tanto de RT quanto de MR. Em complemento, a adicao da cal de carbureto ao solo reduziu o Indice de Plasticidade e aumentou a RCS. Palavras-chave: Passivo ambiental, RCD, cal de carbureto, polimero SBS, estabilizacao quimica. USE OF ENVIRONMENTAL WAST FOR PAVING URBAN ROADS IN MANAUS, AM ABSTRACT Due to the high cost of crushed stone in Manaus, the construction of pavements is executed usually with asphalt sand mixtures and clay material in the base course, which has resulted in the appearance of different pathologies in the urban streets of the city. This study aims to identify alternatives for the pavements of the Manaus city by the use of industrial waste. A binder course with sand from construction residue (WCD) and asphalt cement (AC) modified by styrene and butadiene polymers (SBS) was used. Particularly, it was compared the mechanical behavior of the mixtures with the usual composite (residual sand and pure AC 50/70), through the Tensile Strength (TS) and the Resilience Module (RM). Additionally, in order to contribute to the solution of problems related to the sub layers, carbide lime (by-product from the manufacture of acetylene gas) was added to the clay soil and its performance was analyzed by Unconfined Compression Test (UCT). The results have shown that for the asphalt mixture, the inclusion of SBS polymer increases the TS, while WCD sand gave higher values both for TS and RM. Furthermore, the addition of carbide lime to soil decreases the plasticity index and enhances the UCT. Keywords: Industrial waste, WCD, carbide, SBS polymer, chemical stabilization.

The purpose of this study is to determine the geotechnical behavior of a clayey surface soil typical to the Manaus region (Amazonas, Brazil), when mixed with ceramic powder from brick residue produced by potteries located in the county of Iranduba, Amazonas, Brazil, and with residual sand (the reference mixture), commonly used in pavements in the region. The density of soil solids was determined, as well as particle size, consistency limits, compaction parameters and mineralogical identification using of X-ray diffraction. The following blends were made: 90% natural soil + 10% additive, 70% natural soil + 30% additive and 50% natural soil + 50% additive. The blends were evaluated according to their physical properties (Atterberg limits, grain size, and compaction) and mechanical behavior (direct shear test). The results for the compositions indicated that the larger the proportion of ceramic residue and sand, the higher the values of the apparent dry density and the lower the optimum moisture; and, in particular, the addition of ceramic residue had a positive effect on the mechanical results, clearly demonstrated by the increase in the cohesion of the 10% blend. These results validate the potential of the residue for use in road work, in addition to the environmental benefits, either as a disposal alternative of an environmental liability or as a form of minimizing natural resource extraction. Keywords: ceramic residue, clayey soil, shear strength

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.

Tendo em vista a necessidade do mercado brasileiro por ligantes que minimizem a prematura falência estrutural dos revestimentos nas vias urbanas, a modificação do cimento asfáltico de petróleo (CAP 50/70) constitui uma excelente opção tecnológica. Nesta pesquisa utilizou-se 2% p/p do copolímero de estireno-butadieno-estireno (SBS) e 2% p/p de fibra natural da casca dos frutos de Couepia edulis (Prance), conhecida como castanha de cutia, material vegetal com característica de reforço e biodisponibilidade na região Amazônica. Os efeitos oxidativos e térmicos, bem como as características físicas dos materiais asfálticos modificados, foram estudados e comparados ao ligante convencional, utilizando-se ensaios estabelecidos pela Agência Nacional de Petróleo, Gás Natural e Biocombustíveis (ANP) e análise térmica - termogravimetria (TG), a fim de determinar as propriedades de degradação e estabilização térmica. Os resultados para os ligantes modificados, confrontados ao ligante tradicional, apresentaram: maior resistência ao envelhecimento, melhorias evidenciadas pelo aumento da consistência, ponto de amolecimento, além da excelente estabilidade térmica em toda faixa de temperatura de utilização (10 ºC a 80 ºC) e aplicação (130 ºC a 170 ºC) dos cimentos asfálticos de petróleo, fornecendo uma opção ao pavimento regional.