TRANSPORTES

Journal Information
EISSN : 22371346
Former Publisher: Programa de Pos Graduacao em Arquitetura e Urbanismo (10.4237)
Total articles ≅ 729
Current Coverage
DOAJ
Archived in
SHERPA/ROMEO
Filter:

Latest articles in this journal

Luis Miguel Gutierrez Klinsky, Vivian Silveira Dos Santos Bardini, Valeria Cristina De Faria
TRANSPORTES, Volume 28, pp 76-86; doi:10.14295/transportes.v28i2.2110

Abstract:
This study used the Multiple Stress Creep Recovery Test (MSCR) and the Flow number test to analyze the characteristics of asphalt rubber and its use in hot mix asphalt (HMA) regarding to their ability to withstand permanent deformation. MSCR tests were done in three commercial asphalt rubber and in the traditional asphalt binder 50/70. Flow number tests were performed in twenty four specimens of asphalt rubber mixtures and eight specimens of conventional asphalt mixtures. The results of these tests showed that all the asphalt rubber samples had lower compliance values (Jnr) in the MSCR test, which denotes that these modified binders improved the rutting resistance of HMA. This behavior was confirmed with flow number results, since the HMA produced with asphalt rubber had always higher flow number values, when compared to the conventional asphalt mixtures. The analysis of the data showed excellent correlation between Jnr values and FN values.
Pedro Bastos De Castro, Bruno Tiago Angelo Da Silva, Suelly Helena De Araújo Barroso
TRANSPORTES, Volume 28, pp 29-40; doi:10.14295/transportes.v28i2.1909

Abstract:
Micro surfacing (MS) is a type of bituminous coating frequently applied in the surface of pavement structures in order to prevent the occurrence of common distress and/or as a maintenance procedure. Micro surfacing has successfully been used in some states of Brazil as well as in many countries all over the world. Local aggregates used for micro surfacing composition are in some cases scarce and/or expensive. Therefore, the main objective of the present research is to verify the technical, financial and environmental viability of using steel slag aggregate (SSA) in micro surfacing applications. To reach the main objective, a procedure was developed in four steps. In the first step it was made the characterization of conventional (granitic) and alternative aggregates (steel slag) and polymer-modified emulsified asphalt. In the second step, mix design, surface abrasion resistance and setting time tests were performed. In the third step, the micro surfacing mechanical performance was analyzed using a laboratory traffic simulator to observe accumulated permanent deformation; surface wear; micro texture and macro texture. In the fourth step, a comparative study of costs concerning micro surfacing application using conventional mineral aggregate (MS-MA) and alternative aggregates (MS-SSA) were performed. The laboratory procedure results indicated that the steel slag studied has the potential to be used in micro surfacing applications with more rutting resistance and better durability. The cost analysis showed for medium transport distances bigger than 60 km, the MS-SSA will be cheaper than MS-MA solution.
Mayara Sarisariyama Siverio Lima, Liseane Padilha Thives
TRANSPORTES, Volume 28, pp 1-13; doi:10.14295/transportes.v28i2.1847

Abstract:
A lama vermelha é um resíduo sólido resultante do processamento do minério de bauxita para obtenção da alumina (óxido de alumínio – Al2O3), que é o principal composto químico para produzir alumínio. O Brasil possui uma grande reserva de bauxita no estado do Pará e o minério é processado em larga escala. No entanto, no país, a lama vermelha tem sido armazenada inadequadamente no meio ambiente. O Pará está situado no norte do Brasil e apresenta alta temperatura durante todo o ano. O elevado volume de tráfego e as altas temperaturas contribuíram para o surgimento precoce de defeitos nos revestimentos asfálticos dos pavimentos flexíveis. Este estudo laboratorial visa à introdução deste resíduo como fíler em misturas asfálticas densas. Para tanto, foram produzidas misturas de asfalto com 3%, 5% e 7% de lama vermelha (tamanho nominal entre 0,02 a 2.800 micrometros). Como referência, foi produzida uma mistura convencional com 7% de fíler de pó de pedra (tamanho nominal inferior a 0,075 mm). A resistência à deformação permanente das misturas foi avaliada através do simulador de tráfego francês. Como resultado, a mistura com 5% de lama vermelha apresentou o melhor desempenho à deformação permanente e obteve, aos 30.000 ciclos, a porcentagem de afundamento de 3,5%. As misturas asfálticas com lama vermelha apresentaram bom desempenho, com redução da deformação permanente de 12,63 a 42,62% em relação à mistura de referência. A lama vermelha como fíler em misturas asfálticas mostrou ser uma opção viável para reutilizar este resíduo, além de ser uma alternativa ecologicamente adequada.
Breno Barra, Leto Momm, Yader Guerrero, Yves Brosseaud, Gustavo Momm
TRANSPORTES, Volume 28, pp 41-53; doi:10.14295/transportes.v28i2.1927

Abstract:
The main aim of this paper is to present the development and validation procedures of the first brazilian french-based asphalt mix complex modulus and fatigue test apparatus, so-called FADECOM, in order to demonstrate the effective application of the results obtained in pavement design procedures. Magnetic sensitive Hall Effect non-contact captors determine amplitude displacement, while loading cells capture force amplitude by a diaphragm system. Independent cooling and heating chambers assure a precise temperature control comprising a range from -30ºC to above 100ºC with an accuracy of 0.1ºC. A frequency inverter controls the emission of pulses usually set from 1Hz to 30Hz. For validating the apparatus, a scientific cooperation agreement was dealt with French Institute of Transportation Sciences and Technologies, Development and Road Network (IFSTTAR), in which specimen samples were tested in both UFSC and IFSTTAR laboratories. The crossed-results obtained indicate an excellent performance and accuracy of FADECOM apparatus, presenting variations around just 3 microstrains in determining fatigue strains at 106 cycles (e6) and less than 10% related to the complex stiffness modulus, demonstrating huge accuracy of the FADECOM apparatus and its practical feasibility to be applied in pavement design procedures, based on the technical principles of French methodology.
Camila Kern, André Luiz Bock, Washington Peres Núñez, Jorge Augusto Pereira Ceratti
TRANSPORTES, Volume 28, pp 63-75; doi:10.14295/transportes.v28i2.2082

Abstract:
Highways are the mode of transport used for the transportation of the majority of loads and passengers in Brazil; however, the lack of conservation of pavements has caused several economical losses to the country. Only through suitable pavement management the rehabilitation measures taken might ensure a satisfactory level of service. The present research aimed at evaluating the performance of two pavement sections of the federal highway BR-448/RS, in southern Brazil. For three years, the evolution of the pavement structural capacity and functional condition were followed in order to propose performance trends. Deflections, permanent deformations, and surface defects surveys scarcely varied and were quite low due to the thick asphalt layers used (19 cm). On the other hand, segregation of the asphalt mixture was observed when the final layer was laid. That segregation affected pavement texture, reduced tire-road friction, and caused the formation of surface water films; thus, reducing the road safety. In general, the proposed trend lines predicted quite accurately the pavement performance throughout the period evaluated and will be used in the MeDiNa software database for the creation of a new Brazilian pavement design method.
Matheus S. Gaspar, Kamilla L. Vasconcelos, Manuela M. Lopes, Liedi L. B. Bernucci
TRANSPORTES, Volume 28, pp 87-99; doi:10.14295/transportes.v28i2.2133

Abstract:
A produção de misturas asfálticas com teores elevados de material fresado (RAP) sem prejuízo ao desempenho em campo ainda é um desafio. Nas reciclagens a quente e morna, o ligante presente no RAP é ativado, mas não se sabe quanto dele efetivamente interage com o ligante novo. Neste trabalho, é aplicado um procedimento laboratorial de extração por etapas que busca avaliar a homogeneidade do ligante asfáltico em duas misturas mornas produzidas em usina, uma delas com 25% RAP e a outra sem RAP (mistura de controle). As “camadas” de ligante obtidas foram testadas no Reômetro de Cisalhamento Dinâmico. Os resultados mostraram que, para a mistura com 25% RAP, os parâmetros analisados variaram de forma progressiva, diferente da mistura de controle. O procedimento se mostrou útil para avaliar a homogeneidade do ligante, o que está relacionado ao grau de interação entre ligantes e pode ser usado para assegurar um bom desempenho.
Francisco José Pereira De Almeida, Suyanne Costa Silva, Jorge Barbosa Soares, Evandro Parente Junior
TRANSPORTES, Volume 28, pp 100-110; doi:10.14295/transportes.v28i2.2163

Abstract:
This paper presents the algorithm for calculating the damage characteristic curve obtained in direct tension tests taking into account sinusoidal controlled strain loading. The Viscoelastic Continuum Damage formulation is presented in a summarized form for the algorithm, in which the pseudo strain, at the instants associated to the observed stress, is calculated using the expression of the linear viscoelasticity stress under controlled strain testing. This facilitates subsequent treatment of the data to obtain the vs. curve. The proposed algorithm is simple to understand and easy to implement computationally. The algorithm was validated with the results of fatigue test simulations in three mixtures, which have indicated its potential.
Ana Sofia Figueroa Infante, Fredy Reyes Lizcano, Néstor Cely Leal
TRANSPORTES, Volume 28, pp 54-62; doi:10.14295/transportes.v28i2.2071

Abstract:
One of the most common problems pavements have is the loss of adhesion and cohesion due to moisture damage. Tropical countries and rainy seasons are some of the causes for this type of distress on roads. Another factor that has high influence in this damage is the mineralogy of the aggregate. This research shows the results of adhesion and cohesion between the aggregates from a limestone quarry and two types of sandstones from different quarries, highly used for roads projects from Colombia, and the asphalt 60-70 (1/10) mm, same PG58-22. For determining the adhesion and cohesion, Bitumen Bond Strength tests were made for dry and wet conditions. In addition, the Surface Free Energy was measured for the aggregates and the asphalt. The results indicated that those type of aggregates are highly susceptible to moisture damage, due all values of humidity Index Damage (HDI) were less than 0,5. This indicates that it is necessary to use modifiers for controlling the stripping of the pavements due to Moisture Damage.
Gracieli Bordin Colpo, Lélio Antônio Teixeira Brito, Dionísio Doering, Douglas Martins Mocelin, Ana Paula Hilgert, Marlova Johnston, Jorge Augusto Pereira Ceratti
TRANSPORTES, Volume 28, pp 14-28; doi:10.14295/transportes.v28i2.1907

Abstract:
A fadiga é caracterizada pela deterioração estrutural de um material quando submetido a repetidos esforços de tensão-deformação. O ensaio laboratorial comumente empregado no Brasil para análise de fadiga em misturas asfálticas é o ensaio de tração indireta (IDT). Como alternativa ao ensaio IDT, o ensaio de flexão em quatro pontos (4PBBT) submete o material a um estado de tensões mais realístico em relação ao campo. Este trabalho avaliou o comportamento à fadiga de uma mistura asfáltica com ligante modificado por polímero (PG76-11) usando os ensaios IDT e 4PBBT. Um segmento da rodovia BR-116/RS, pavimentado com o mesmo material, foi instrumentado para monitorar as respostas mecânicas na camada asfáltica, permitindo a avaliação do material sob condições de tráfego real, e através do monitoramento ao longo do tempo, permitindo melhor entendimento do desgaste estrutural. Em relação aos ensaios laboratoriais, o ensaio 4PBBT apresentou uma melhor relação com o observado em campo.
Francisco Heber Lacerda De Oliveira, Renan Santos Maia, Gledson Silva Mesquita Júnior, Wilkens Martins Dos Santos
TRANSPORTES, Volume 28, pp 160-174; doi:10.14295/transportes.v28i1.1934

Abstract:
Inadequações relativas ao projeto geométrico podem ser consideradas comuns em aeroportos pelo mundo. No Brasil, alguns aeroportos apresentam inconformidades de separação entre eixos de pistas de pouso e decolagem e de taxiamento paralelas que são inferiores aos requisitos exigidos pela Agência Nacional de Aviação Civil. Este trabalho objetiva avaliar o impacto de tal situação no risco de colisões associado a operações simultâneas de aeronaves em condições de operação por instrumentos. Para tanto, foi utilizado um método de análise de risco proposto pelo Airport Cooperative Research Program do Transportation Research Board com aeronaves de três categorias distintas que operam no Aeroporto Internacional de Fortaleza. Percebeu-se que há probabilidades reduzidas de acidentes acontecerem nestas condições, sendo o método apresentado um meio relevante para a análise quantitativa dos riscos operacionais em tais situações de inconformidade, podendo esta abordagem ser aplicada em casos similares.
Back to Top Top