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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Estudo da aplicação do resíduo de areia de sílica base como fíler em misturas asfálticas

Costa, Karine Jussara Sá da 30 April 2010 (has links)
Made available in DSpace on 2015-04-22T22:08:55Z (GMT). No. of bitstreams: 1 Dissertacao Karine Jussara da Costa.pdf: 6916532 bytes, checksum: 872f531f6e30b510bea0beb9ae62b8a9 (MD5) Previous issue date: 2010-04-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This teses research analyses, m ky trough an experimental project, the mechanical behavior of hot-mix asphalt, with dust of sand. The dust of sand residue was utilized as a filler in hot-mix asphalt, replacing in the Manaus city used material the Portland cement CP II. The general purpose of this work is to test hypothesis that the residue can be use as a filler in hot-mix asphalt. The reuse of these industrial residues leads to environmental gains; it not only helps to avoid the open-air deposition of this by-product but it also reduces. All the mixtures were characterized mechanically through the testing of Resilient Modulus, Static Tensile Strength, fatigue of diametrical compression under controlled stress and static creep. The results of this research show that the addition of industrial residue in hot-mix asphalt increases the binder consumptio / Esta pesquisa analisa por meio de um estudo experimental, o comportamento mecânico de misturas asfálticas, utilizando o resíduo pó de areia. O objetivo geral desta pesquisa é testar a hipótese que o resíduo pode ser utilizado como fíler em misturas asfálticas. O resíduo pó de areia foi utilizado como fíler em mistura asfáltica tipo CBUQ, em substituição ao cimento Portland CP II usado na cidade de Manaus. A reutilização destes resíduos industriais traz benefícios ambientais, pois auxilia a questão de deposição destes rejeitos. Todas as misturas foram caracterizadas mecanicamente através dos ensaios de Módulo de Resiliência, Resistência à Tração estática por compressão diametral, fadiga por compressão diametral à tensão controlada e compressão axial estática (creep estático). Os resultados obtidos demonstraram que a adição do resíduo industrial estudado em mistura asfáltica aumenta o consumo de ligante da mistura. Os resultados dos ensaios mostram desempenho adequado da mistura confeccionada com o pó de areia.
12

Análise das propriedades de misturas asfálticas com pelete e agregados de resíduos de concreto

Marques, Vagner da Costa 21 February 2014 (has links)
Made available in DSpace on 2015-05-14T12:09:34Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2919741 bytes, checksum: e2646db8015a4181da35e3ee2b1a0e33 (MD5) Previous issue date: 2014-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This dissertation is included in area of reuse of solid wastes in paving, with objective to use recycled concrete aggregates and pellet in asphaltic surface course. The aim of the research was to analyze the technical feasibility of asphalt mixtures made with recycled concrete aggregates and pellet, in partial replacement of natural aggregates of the conventional asphalt mix, from tests of physical characterization of aggregates and mechanical performance of asphalt mixtures. The materials used were crushed stone 19 mm, crushed stone 12 mm, crusher dust, recycled concrete aggregate, pellet and 50/70 pen asphalt cement, these materials were obtained from companies in the state of Paraíba. For natural aggregates were performed grading, Los Angeles abrasion, absorption and density. For recycled concrete aggregates were made grading and specific density, and for pellet was carried out grading. One conventional asphaltic mixture were produced containing natural aggregates (crushed stone 19, crushed stone 12, crusher dust) and 50/70 pen asphalt cement, and five asphaltic mixtures were made with partial replacements of crusher dust for recycled concrete aggregates and pellet, in proportions: i) 25% of recycled concrete aggregates; ii) 2% of pellet; iii) 4% of pellet; iv) 23% of recycled concrete aggregates with 2% of pellet, and v) 21% of recycled concrete aggregates with 4% of pellet. The C grading envelope was used and chosen according to DNIT ES 031/2006. The mixtures were performed by the Marshall mix design. The mechanical tests performed were Marshall stability, tensile strength by diametric compression, resilient modulus and Lottman test. The hot asphalt mix containing 75% of natural aggregates, 23% of recycled concrete aggregates and 2% of pellet showed greatest number of parameters in accordance with the technical standards, as a result the best technical viability / Esta dissertação está inserida na problemática de reaproveitamento de resíduos sólidos na pavimentação, buscando o emprego de agregados de resíduos de concreto e pelete em revestimentos asfálticos. O objetivo da pesquisa foi analisar a viabilidade técnica de misturas asfálticas feitas com agregados de resíduos de concreto e pelete, em substituição parcial aos agregados naturais de mistura asfáltica convencional tipo CBUQ, a partir de ensaios de caracterização física dos agregados e de desempenho mecânico das misturas asfálticas. Os materiais empregados foram brita 19, brita 12, pó de pedra, agregados de resíduos de concreto, pelete e CAP 50/70, obtidos de empresas do Estado da Paraíba. Para os agregados naturais foram realizados a granulometria, abrasão Los Angeles, absorção e densidade. Para os agregados de resíduos de concreto foram realizados os ensaios de granulometria e massa específica, e para o pelete foi realizada a granulometria. Seis misturas asfálticas foram realizadas, sendo uma mistura de referência com os agregados naturais (brita 19, brita 12 e pó de pedra) e CAP 50/70; as demais misturas foram feitas com substituições parciais do pó de pedra pelos agregados de resíduos de concreto e pelete, nas proporções: i) 25% de agregados de resíduos de concreto; ii) 2% de pelete; iii) 4% de pelete; iv) 23% de agregados de resíduos de concreto com 2% de pelete, e v) 21% de agregados de resíduos de concreto com 4% de pelete. A faixa granulométrica utilizada foi a faixa C, que foi escolhida com base na norma DNIT 031/2006 ES. As dosagens realizadas foram por meio do método Marshall. Os ensaios mecânicos realizados foram estabilidade Marshall, resistência à tração por compressão diametral, módulo de resiliência e o ensaio Lottman. A mistura asfáltica tipo CBUQ com 75% de agregados naturais, 23% de agregados de resíduos de concreto e 2% de pelete se apresentou com maior número de parâmetros em conformidade com as normas técnicas, o que evidenciou sua maior viabilidade técnica em relação às demais misturas asfálticas modificadas
13

Propuesta de una carpeta de Warm Mix Asphalt con adición de caucho reciclado para mejorar la respuesta de las vías en intersecciones urbanas ante los efectos de congestión y sobrecarga vehicular. Caso: Jr. García Naranjo y Av. Mendoza Merino, en el Distrito de La Victoria, Lima / Proposal of a Warm Mix Asphalt pavement with the addition of recycled rubber to improve the response of urban intersection roads to the effects of congestion and vehicular overload. Case: Street García Naranjo and Mendoza Merino Avenue, in the District of La Victoria, Lima

Marceliano Alcantara, Luis Alberto, Sandoval Moreno, Lucero Francia 02 July 2021 (has links)
En muchas ciudades el crecimiento de la congestión vehicular es mayor al crecimiento poblacional. Las ciudades con mayor congestión en el mundo son Bombay, Bogotá y Lima. Esta última cuenta con un nivel de congestión vehicular aproximado del 66%, este se puede medir mediante la saturación de la vía realizando un estudio HCM. Estudios previos han analizado la influencia de la temperatura, velocidad, y carga sobre la carpeta asfáltica. Debido a esto, el impacto de la congestión debería considerarse en el diseño de pavimentos urbanos. La investigación, verificó que la congestión tiene una influencia en el incremento de la temperatura de la superficie del pavimento, la reducción de la velocidad y el aumento de carga vehicular. Se calculó que a mayor temperatura y menor velocidad se reduce el módulo de elasticidad de la carpeta asfáltica. Para esto, se consideró una diferencia de temperatura con y sin congestión, de 35°C y 25°C respectivamente. Se ha propuesto una carpeta asfáltica tibia con adición de caucho al 18% que pueda soportar los efectos de la congestión vehicular. Se buscó reducir las deformaciones máximas de la carpeta y aumentar el número de ciclos de repetición de carga que puede soportar el pavimento, para que estos sean adecuados a los efectos de la congestión. Esto se logra al incrementar el módulo de elasticidad. Finalmente, se obtuvo un aumento del 45% en el módulo de elasticidad, una reducción del 50% de deformaciones permanentes, y un aumento del 500% aproximadamente en el número de ciclos de carga. / In many cities, the increase in traffic congestion is greater than population growth. The most congested cities in the world are Bombay, Bogota and Lima. The latter has an approximate congestion level of 66%, which can be measured by road saturation using an HCM study. Previous studies have analyzed the influence of temperature, speed, and load on the asphalt surface. Because of this, the impact of congestion should be considered in urban pavement design. The research verified that congestion has an influence on the increase of pavement surface temperature, the reduction of speed and the increase of vehicular load. It was calculated that the higher the temperature and the lower the speed, the lower the modulus of elasticity of the asphalt layer. For this purpose, a temperature difference of 35°C and 25°C with and without congestion, respectively, was considered. A warm asphalt pavement with 18% rubber was proposed to withstand the effects of vehicular congestion. The aim was to reduce the maximum deformations of the binder and increase the number of load repetition cycles that the pavement can withstand, so that they are adequate to the effects of congestion. This is achieved by increasing the modulus of elasticity. Finally, a 45% increase in the modulus of elasticity, a 50% reduction in permanent deformations, and an increase of approximately 500% in the number of load cycles were obtained. / Tesis
14

Quantification of the Role of The Effective Binder in the Performance of RAP – WMA Mixtures

ALSALIHI, MOHAMMED, 0000-0003-1930-5392 January 2020 (has links)
Over the past decades, several new technologies/materials (such as WMA, RAP, rubber, polymers, bio-binders…etc.) were incorporated into asphalt mixtures. However, current mix-design specifications evaluate all mixtures containing these different additives/technologies based on volumetric. Further, RAP incorporation in asphalt mixtures is still limited, and the influence of lowered production temperatures on RAP contribution in RAP-WMA mixtures is understudied. To tackle these issues, this study presents a comprehensive evaluation of the effect of production factors ( RAP content and source, binder grade, and production temperatures) on the effective binder in WMA-RAP mixtures, and the role of the effective binder in controlling mixture performance.The experimental program included evaluation of the compaction, cracking, and rutting performance of WMA-RAP mixtures produced with a different combination of the production factors. The Semi-Circular Bend (SCB) test at intermediate temperatures was used for cracking evaluation, while the Indirect Tension Test at High Temperatures (IDT-HT) was used for rutting evaluation. Further, the study included rheological characterization of extracted binder from the mixtures to investigate the role of the effective binder on cracking performance. The results showed that the effective binder properties are changed significantly with changes in the production factors, as measured by the extracted binder rheological properties. Also, the properties of the effective binder showed a direct control of the mixture performance as measured by the IDT-HT strength and the flexibility index obtained from the SCB test. Binder selection limits were developed for lab-produced WMA-RAP mixtures based on the Glover-Rowe parameter. Finally, a validation study was conducted using data from four different projects, including a field project in Texas, FHWA’s accelerated loading facility, a laboratory mixture study in Wisconsin, and a New Hampshire DOT study to confirm the refine the findings of this study. / Civil Engineering
15

Propuesta Teórica de Diseño de Mezcla Asfáltica en Caliente producida a Temperatura Ambiente Menor a Seis Grados Centígrados en Perú / Theoretical proposal of design of hot asphalt mix produced at a room temperature below six degrees centigrade in peru

Chavez Cervantes, Holmer Pitter, Pezo Irazabal, Anders 23 August 2020 (has links)
La presente investigación hace mención al análisis en laboratorio con respecto a la colocación de asfalto a una temperatura menor a seis grados centígrados, teniendo en consideración que el Perú cuenta con diferentes tipos de climas a lo largo y ancho de su territorio, esto hace que la producción de asfalto y su colocación sea una dificultad para cualquier tipo de proyecto de carreteras, la cual nos dirige a una realidad en la producción de asfalto en caliente, ya que sabiendo las normas y manuales con las que actualmente contamos hace que la colocación sea imposible a una temperatura menor a seis grados centígrados. La investigación se focaliza en un análisis cualitativo – cuantitativo la cual debe cumplir con los parámetros de calidad (Ensayos), manual de carreteras (EG - 2013) y proceso constructivo (método Marshall) la realización de la propuesta de mezcla asfáltica va a variar en el porcentaje de diferentes tipos de filler que hemos considerado para la investigación (cal, cemento portland tipo I y sílice). Para los ensayos se realizaron probetas sin ningún tipo de aditivos, las probetas una vez preparadas a 140ºC se sometieron a congelamiento dando como resultado, de los tres tipos de filler, que la mezcla asfáltica en caliente con incorporación de cemento portland tipo I a un 5,90% de cemento asfáltico es el óptimo cumpliendo con los parámetros y especificaciones técnicas del manual de carreteras. / The present investigation mentions the laboratory analysis regarding the placement of asphalt at a temperature below six degrees centigrade, taking into account that Peru has different types of climates throughout its territory, this makes the asphalt production and its placement is a difficulty for any type of road project, which leads us to a reality in the production of hot asphalt, since knowing the standards we currently have, that makes placement impossible to a temperature below six degrees centigrade. The research is focused on a qualitative - quantitative analysis which must comply with the quality parameters (Tests), road manual (EG - 2013) and constructive process (Marshall method) the realization of the asphalt mix proposal will vary in the percentage of different types of filler that we have considered for the research (lime, portland cement type I and silica). For the tests, test tubes were carried out without any type of additives, once the test tubes were prepared at 140ºC, they were subjected to freezing, resulting, of the three types of filler, that the hot asphalt mix with incorporation of portland cement type I at a 5,90% asphalt cement is the optimal one complying with the parameters and technical specifications of the road manual. / Tesis
16

Využití tenkých obrusných vrstev s vysoce polymerem modifikovaným asfaltem / Usage of thin wearing courses with highly polymer modified bitumen

Renza, Jaroslav January 2019 (has links)
The diploma thesis deals with technology for the implementation and use of asphalt concrete for very thin layers (BBTM) with use of asphalt binder of high-polymer modification (HiMA). Further, there are described selected and performed functional tests. Thesis also contains design of a mixture for bituminous concrete type targeted for very thin layers with different types of binders. After a suitable design of the mixture, laboratory tests were carried out (stiffness modulus, resistance to permanent deformation, low temperature characteristics, water resistance and particle loss). The output of this work is a set of measured values and processed results with their interpretation.
17

Vlastnosti asfaltových směsí typu SMA s R-materiálem / Properties of asphalt mixtures of SMA-type with RAP

Acuna Subia, Luis Carlos January 2018 (has links)
The aim of the diploma thesis is to verify and compare the properties of bituminous stone mastic asphalt, namely SMA 11S with modified PMB 45 / 80-55 asphalt binder or 50/70 road bitumen binder with rubber granulate. Comparison of properties is performed using functional tests. The thesis is divided into the theoretical and practical part. The theoretical part deals with the familiarization with the use of the SMA mixture, the selected concepts concerning recycling of non-leveled roads are described and described. Attention is paid especially to the recycling of roads in the Czech Republic with an emphasis on hot recycling on the incinerator, which allows increased dosing of Reclaimed Asphalt into asphalt mixtures. In the practical part, the results of the functional tests of the SMA 11S mixture, which have been taken from the test section, are processed and evaluated.
18

Asfaltové směsi se zpěněným asfaltem / Foam asphalt mixtures

Brtníková, Tereza January 2020 (has links)
The diploma thesis is divided into theoretical and practical part. The theoretical part is mainly focused on methods for reducing the working temperature in the production of hot mix asphalt and the main reasons for this. Most attention is paid to the warm mix asphalt, mainly foam asphalt technology. In practical part are describes working procedures of individual tests on asphalt mixtures and recovered bitumen binders. The tests were performed on 3 types of ACO 11+, one was made with working temperature 160°C without foamed bitumen and the other two with foamed bitumen,one with working temperature 160°C and the second 140°C. Then were the results compared.

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