82 resultados para Pavimentação


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This research presents a study investigating the correlation between the environmental-physycal charcateristics of cities and the formation of its micro-climates. The study was conducted in the central area of Fortaleza characterized as a stable and consolidated area, where the city originated and currently faces serious problems in its urban dynamics. The points of measurements were determined by the elaboration and analysis of topography maps, height of buildings, land use, type of surface coating and vegetation, following the methodology of Katzschner (1997). A zoning map was then determined, according to common morphological characteristics of the 12 measurement points, which were based on a set of Romero s (2001) bioclimatic criteria. Air measurements, temperature, humidity, intensity and direction of winds were made in transect form in two different circuits in the study area, with six points of data collection in each area, in three different times: 6:00 am, 1:00pm and 7:00pm, during two periods of the year: August 2008 and March 2009. The results verified the influence of different environmental-physical types in the behavior of the climatic variables that were collected. A verticalização tão condenada em algumas situações se bem equilibrada e controlada pode reduzir as temperaturas do ar através do sombreamento dos espaços urbanos e possibilidade de maior permeabilidade a ventilação natural. The highest average air temperature and lower humidity were recorded at the point I at all times. This situation may have been in result of the high density, poor vegetation and extended paving of the ground. According to the results, it s clear the positive influence vegetation has on easing air temperature. Another indicator observed that areas with a greater variation in building heights tend to present decreased average air temperature. High rise structure, planned in accordance to urban air quality parameters, can reduce air temperatures by the shading of urban spaces and the possibility of greater penetration of natural ventilation

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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

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The municipal district of Equador-RN is located in an area of great amounts of ores, being your main economical activity the extraction and the kaolin improvement. The main originating from environmental problem that activity is the amount of generated residue, about 70% of the extracted kaolin. The residues are simply piled up in lands of the improvement companies, occupying like this a large area and causing impact in the existent flora. When dry, the residues transform powdered and for the action of the wind, they disperse, polluting the air. Being like this, the present work has as objective evaluates the incorporation of the great residue, originating from of the kaolin improvement, in partial substitution of all the employed aggregates in a conventional mixture of asphalt concrete, which was used in the paving of BR101/RN061 - passage between Ponta Negra and Ares. That evaluation was accomplished in three stages. The first refers to the evaluation of the physical, thermal and mineralogical characteristics of the residue with the intention of to classify it and to define your application as aggregate (small and great). The second refers to the physical characterization of the aggregates and of the asphalt material used in the conventional mixture. And the third, to the evaluation of the mixtures containing residue, which were elaborated starting from the conventional mixture with the gradual incorporation of the residue, from 5 to 40%, in substitution to the part of the conventional aggregates, in way to obtain similar particle size curves the one of the conventional mixture. That evaluation was accomplished through the comparison between the volumetric composition, the mechanical behavior and the susceptibility to the humidity of the mixtures containing residue with the one of the conventional mixture, and with the one of the DNIT specifications. The results show that the great residue originating from of the kaolin improvement has grains of the most varied size, being like this, it can substitute part of all the conventional aggregates and of the filler in an asphalt mixture. Besides, your mineralogical composition presented the same present minerals in the composition of conventional aggregates used in paving. The results evaluation of the volumetric composition of the mixtures containing residue indicates that it can use up to 30% of residue in substitution to the conventional aggregates. The evaluation of the mechanical behavior of those mixtures indicates that the residue increment in the studied mixtures caused an increase of the stability and a reduction of the resistance to the traction. The values obtained in the resistance to the traction meet below the minimum value specified by DNIT, but close to the value obtained in the conventional mixture. When taking in consideration the susceptibility of the same ones to the humidity, the results indicate that she can use up to 25% of residue

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Educação Matemática - IGCE

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Geociências e Meio Ambiente - IGCE

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The paper discusses the application of High Strength Concrete (HSC) technology for concrete production with the incorporation of Rice Husk Ash (RHA) residues by replacing a bulk of the material caking and rubber tires with partial aggregate volume, assessing their influence on the mechanical properties and durability. For concrete with RHA and rubber, it was possible to reduce the brittleness by increasing the energy absorbing capacity. With respect to abrasion, the RHA and rubber concretes showed lower mass loss than the concrete without residues, indicating that this material is attractive to be used in paving. It is thus hoped that these residues may represent a technological and ecological alternative for the production of concrete in construction works.

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The intensive development in the urbanization process implied a series of economic, social, and gradually, environmental transformations, essentially, since its intensification, which took place from the Industrial Revolution in Europe and North America. In Latin American countries, including Brazil, there was such acceleration in urban sprawl, only in the middle of the twentieth century, fomented by a peculiar industrialization, coming from the scientific-technical revolution, which occurred in developing countries. In this context, and with a lack of planning and an effective organization, cities of the dependent countries face an inordinate population growth and an unprecedented industrial swelling. Brazil, following this trend, presents several issues regarding the gaps in the provision of necessary infrastructure to meet the most basic needs of its population and the intense activity and anthropogenic effects on the environment. In this sense, environmental problems, related to air and water pollution, degradation and contamination of soil, paving roads, reduction of green areas, urban heat island, among others, reaching ever deeper into the Brazilian urban areas. It is important the analysis in this final project, the weather events related to episodes of strong winds and the events and the impacts to the population of Rio Claro (SP) in the period 2005 to 2010, basing themselves in Geographical Climatology and Urban climate studies. In this scenario, we found the prevalence of occurrences linked to falling trees in the study area, connected, at the same time, to the occurrence and to the absence of episodes of extreme events, with measurements of strong winds, showing a connection between the events and external facts to episodes of winds

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The large volume of waste generated by construction and demolition has become increasingly a matter of concern to society. The handling and disposal of RCD's to gain prominence as over the years intensified the requirements for a sustainable world. This paper presents the positive and negative factors that the management of construction and demolition waste can bring in the municipality of Guaratinguetá-SP. This study examines the methods used in waste management since he was not done any treatment to the present day. Presents comparative tables on the feasibility of installing a central crushing of inert waste and implementation of an inert waste landfill in the municipality of Guaratinguetá and Cachoeira Paulista. And yet the work being done by the city of Guaratinguetá reuse the material in class A in paving roads

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Com o intuito de promover uma ação internacional para a gestão sustentável, conservação e desenvolvimento das florestas e chamar a atenção da população para o papel destas na geração de benefícios econômicos, sociais e ambientais, principalmente para os povos que dependem delas para sobreviver, a Assembléia Geral da Organização das Nações Unidas (ONU), declarou 2011 como o Ano Internacional das Florestas. Paradoxal a esta ação, o ano de 2011 é também marcado pela inauguração da Rodovia Interoceânica Sul (IOS) no Peru, que ao conectar-se a malha rodoviária brasileira cria um elo de ligação direta entre o Oceano Atlântico e o Oceano Pacífico. Segundo seus idealizadores, o projeto aumentará as possibilidades de comércio internacional. Além de incrementar o comércio bilateral e integrar a Macro-Região Sul do Peru ao restante do país, a IOS proporciona ao Brasil uma alternativa de acesso ao Oceano Pacífico e aos mercados da Ásia e, ao Peru, um acesso mais eficiente ao Atlântico e aos mercados da costa leste dos EUA e da Europa. Por outro lado, a IOS passa por uma das mais preservadas regiões da Amazônia e, é considerada de importância única em termos de risco para os esforços mundiais de conservação da biodiversidade e de respeito aos direitos das últimas populações humanas que ali vivem sem ou com muito pouco contato com a sociedade moderna. Os impactos socioambientais ligados à construção e/ou reabilitação de estradas em territórios tropicais úmidos adquiriram fama mundial precisamente com a BR- 364, trecho principal desse corredor no território brasileiro. A pavimentação desta estrada nos anos 1980 provocou desastres ambiental e social gravíssimos no norte de Mato Grosso, em Rondônia e no Acre. Desta forma, a presente pesquisa tem por objetivo fazer um estudo... (Resumo completo, clicar acesso eletrônico abaixo)

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CONAMA Resolution 307 / 02, in Article 4, states that the primary goal of those involved in the reuse process of construction and demolition waste is not the generation of such wastes, secondarily is the reduce, reuse, recycling and proper disposal of such material. The disposal problem of large volumes of waste generated coupled with the scarcity of natural resources and environmental degradation involved in the extraction process of such materials resulted in several studies, that after many analyzes proposed various forms of reuse and recycling . The NBR 15.116/04 provides requirements for the use of recycled aggregates in paving and concrete without structural function. This work aims to show the usage potential of recycled aggregates from waste generated in construction and demolition sampled Group AB Areias, Pindamonhangaba (SP) in order to meet the standards in Brazil, as well as the environmental contribution by reducing the use of raw materials extracted from nature. After stabilization and particle size analysis of the California Bearing Ratio and Proctor, obtained mixtures of recycled aggregates showed higher values submitted by the minimum standards related, with excellent potential for use in paving

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)