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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.
1

Identifiering av lakbara potentiellt farliga ämnen i gummiasfalt / Identification of leachable potential harmful substances in rubber asphalt

Gustavsson, Jakob January 2010 (has links)
<p>The main purpose of the project was to identify potential environmentally harmful substances which can be leached from rubber asphalt. A method for analysing asphalt was developed and three rubber asphalt materials were analysed after being cryogrinded. One of the materials was also tested in a road machine made for testing of asphalt paving. The particles created in the machine were analysed in the same manner as the cryogrinded asphalt materials.</p><p>The asphalt materials were leached by water during 24 hours. The leachates were extracted with dichloromethane, dried with sodium sulphate and concentrated to a small volume. The extracts were analysed with gas chromatography-mass spectrometry (GC-MS). Due to low concentrations of substances the GC-MS was operated in SIM-mode (Selected Ion Monitoring). Thirteen substances were chosen for the analysis. The substances were aniline, benzothiazole, butyl benzyl phthalate, bisphenol-A, decanoic acid, dibutyl phthalate, diethylhexyl phthalat, phenanthrene, chrysene, naphthalene, 4-n-nonyl phenol and 4-tert-octyl phenol. Benzothiazole and 4-tert-octyl phenol were detected and quantified in the leachates.</p><p>In addition to the analysis of organic substances, pH was measured too. The leachates produced in this project were also sent to an analysis company for several analyses, for example analysis of metals and sulphur. Toxicity tests were performed on the same leachates within an exam work made by Gro Runeman at Lund University. The results of the metal analysis, sulphur analysis, and toxicity tests are not covered within the scope of this report. For the results of these tests and analyses, see Gro Runeman’s report: <em>Evaluating toxicity of asphalt leachates</em>.</p> / <p>Detta examensarbete är utfört vid Statens Geotekniska Institut (SGI). Huvudsyftet med arbetet är att identifiera potentiellt miljöfarliga ämnen som kan laka ut från gummiasfalt. En metod för analys av asfalt har tagits fram och tre olika gummiasfalter har analyserats efter att ha kryomalts. En av dessa asfalter har också använts i en provvägmaskin där det damm som bildades har samlats upp och analyserats. Inom ramen för examensarbetet har också en litteraturstudie gjorts för att bland annat ta reda på vad som är gjort inom området sedan tidigare.</p><p>För att ta reda på vad asfalten innehåller för föreningar gjordes först en fastfasextraktion av krossad (ej kryomald) asfalt där diklormetan användes som lösningsmedel. Från början var tanken att en GC/MS-screening skulle göras för att på så sätt få en överblick av samtliga organiska ämnen som finns i asfalten men på grund av de väldigt låga halterna av i gaskromatografen analyserbara föreningar var det nödvändigt att begränsa analysen till några få föreningar. De föreningar som analysen inriktade sig mot var anilin, bensotiazol, bensylbutylftalat, bisfenol-A, dekansyra, dibutylftalat, di(etylhexyl)ftalat, fenantren, krysen, naftalen, 4-n-nonylfenol, pentaklortiofenol och 4-tert-oktylfenol.</p><p>Laktester utfördes genom att de kryomalda asfaltmaterialen lakades med vatten under 24 timmar. Efter extraktion, torkning och koncentrering analyserades lakextrakten med avseende på de föreningar som hittats vid fastfasextraktionen. I lakvattnen hittades bensotiazol samt 4-tert-oktylfenol. Dessa föreningar kvantifierades genom att en enpunktskalibrering gjordes.</p><p>Utöver analyserna ovan mättes även pH på lakvattnen. Lakvattnen skickades också på metall- och svavelanalys samt turbiditets- och fenolindexmätning till ett större analysföretag. Toxicitetstester har utförts på samma lakvatten av Gro Runeman inom ramen för ett examensarbete vid Lunds Universitet. För resultaten från toxicitetstester, metallanalyser samt turbiditets- och fenolindexmätningar hänvisas till Gro Runemans rapport: <em>Evaluating toxicity of asphalt leachates</em>. Delar av denna rapport är skrivna i samarbete med Gro Runeman.</p>
2

Identifiering av lakbara potentiellt farliga ämnen i gummiasfalt / Identification of leachable potential harmful substances in rubber asphalt

Gustavsson, Jakob January 2010 (has links)
The main purpose of the project was to identify potential environmentally harmful substances which can be leached from rubber asphalt. A method for analysing asphalt was developed and three rubber asphalt materials were analysed after being cryogrinded. One of the materials was also tested in a road machine made for testing of asphalt paving. The particles created in the machine were analysed in the same manner as the cryogrinded asphalt materials. The asphalt materials were leached by water during 24 hours. The leachates were extracted with dichloromethane, dried with sodium sulphate and concentrated to a small volume. The extracts were analysed with gas chromatography-mass spectrometry (GC-MS). Due to low concentrations of substances the GC-MS was operated in SIM-mode (Selected Ion Monitoring). Thirteen substances were chosen for the analysis. The substances were aniline, benzothiazole, butyl benzyl phthalate, bisphenol-A, decanoic acid, dibutyl phthalate, diethylhexyl phthalat, phenanthrene, chrysene, naphthalene, 4-n-nonyl phenol and 4-tert-octyl phenol. Benzothiazole and 4-tert-octyl phenol were detected and quantified in the leachates. In addition to the analysis of organic substances, pH was measured too. The leachates produced in this project were also sent to an analysis company for several analyses, for example analysis of metals and sulphur. Toxicity tests were performed on the same leachates within an exam work made by Gro Runeman at Lund University. The results of the metal analysis, sulphur analysis, and toxicity tests are not covered within the scope of this report. For the results of these tests and analyses, see Gro Runeman’s report: Evaluating toxicity of asphalt leachates. / Detta examensarbete är utfört vid Statens Geotekniska Institut (SGI). Huvudsyftet med arbetet är att identifiera potentiellt miljöfarliga ämnen som kan laka ut från gummiasfalt. En metod för analys av asfalt har tagits fram och tre olika gummiasfalter har analyserats efter att ha kryomalts. En av dessa asfalter har också använts i en provvägmaskin där det damm som bildades har samlats upp och analyserats. Inom ramen för examensarbetet har också en litteraturstudie gjorts för att bland annat ta reda på vad som är gjort inom området sedan tidigare. För att ta reda på vad asfalten innehåller för föreningar gjordes först en fastfasextraktion av krossad (ej kryomald) asfalt där diklormetan användes som lösningsmedel. Från början var tanken att en GC/MS-screening skulle göras för att på så sätt få en överblick av samtliga organiska ämnen som finns i asfalten men på grund av de väldigt låga halterna av i gaskromatografen analyserbara föreningar var det nödvändigt att begränsa analysen till några få föreningar. De föreningar som analysen inriktade sig mot var anilin, bensotiazol, bensylbutylftalat, bisfenol-A, dekansyra, dibutylftalat, di(etylhexyl)ftalat, fenantren, krysen, naftalen, 4-n-nonylfenol, pentaklortiofenol och 4-tert-oktylfenol. Laktester utfördes genom att de kryomalda asfaltmaterialen lakades med vatten under 24 timmar. Efter extraktion, torkning och koncentrering analyserades lakextrakten med avseende på de föreningar som hittats vid fastfasextraktionen. I lakvattnen hittades bensotiazol samt 4-tert-oktylfenol. Dessa föreningar kvantifierades genom att en enpunktskalibrering gjordes. Utöver analyserna ovan mättes även pH på lakvattnen. Lakvattnen skickades också på metall- och svavelanalys samt turbiditets- och fenolindexmätning till ett större analysföretag. Toxicitetstester har utförts på samma lakvatten av Gro Runeman inom ramen för ett examensarbete vid Lunds Universitet. För resultaten från toxicitetstester, metallanalyser samt turbiditets- och fenolindexmätningar hänvisas till Gro Runemans rapport: Evaluating toxicity of asphalt leachates. Delar av denna rapport är skrivna i samarbete med Gro Runeman.
3

Posouzení nízkohlučného asfaltového koberce mastixového s CRmB / Evaluation of Low Noise Stone Mastix Asphallt with CRmB

Zavřel, Tomáš January 2012 (has links)
The aim of diploma thesis is to design mixture SMA LA 8 with crumb rubber modified bitumen (9,9 %) and a modifier additive TecRoad (22 %) and the test of water sensitivity, the resistance to permanent deformation and to frost cracking, the determination of the stiffness and fatigue characteristics. Test methods are described and evaluated.
4

Field and laboratory performance evaluation of a field-blended rubber asphalt. / Avaliação de desempenho em campo e laboratório de um asfalto borracha field blend.

Camargo, Felipe Filizzola 29 April 2016 (has links)
Rubber asphalt has been used in Brazil as early as 2001. Among the fabrication processes of rubber asphalt, the most widely used in Brazil is the terminal blend. However, the use of field-blended rubber asphalt has been around in the United States for decades, especially in the state of Arizona. This process results in a highly viscous material with enhanced engineering properties, but requires specific equipment that is typically installed at the job site, or close to the supplying asphalt plant. Thus, keeping in mind the possible technological advantages of using a field blended rubber asphalt mixture and the lack of information regarding this technique in Brazil, there is a necessity to develop studies to assess the performance of this type of material in our environmental conditions and axle loading configurations. Therefore, a laboratory study was conducted to determine the rheological properties of a field-blended rubber asphalt and compare them to those of typical binders used in Brazil (an AC 30/45 penetration grade and a binder modified with SBS, an elastomeric polymer). Binder permanent deformation was determined using the Multiple Stress Creep and Recovery (MSCR) test, whereas binder fatigue behavior was determined using the Time Sweep and Linear Amplitude Sweep (LAS) tests. Subsequently, the permanent deformation and fatigue behavior of a gap-graded mixture using the field-blended rubber asphalt were assessed in the laboratory and in the field. The permanent deformation of the mixture was determined in the laboratory using the LCPC wheel track test, whereas the fatigue behavior was determined using the four point bending flexural test. A test section was built after the rehabilitation job of highway RJ-122, where a field-blended rubber asphalt mixture was first used in the country. The mixture performance was studied in situ through accelerated pavement tests using a full scale, large mobile traffic simulator. The results were used to model the performance of the structure with the rubber asphalt mixture by means of the Highway Development and Management Model (HDM-4) cracking and permanent deformation models, calibrated to local conditions. Accelerated pavement tests were validated through periodic pavement monitoring campaigns conducted for four years in a test section in Highway RJ-122. The field-blended rubber asphalt showed a good performance in terms of permanent deformation and fatigue determined in the laboratory at the binder and mixture levels, which confirms what was verified in the field. / No Brasil, o asfalto-borracha vem sendo utilizado desde meados de 2001. Dentre os processos de fabricação do asfalto-borracha, o mais utilizado no Brasil é o asfalto-borracha estocável ou terminal blend. Contudo, o asfalto-borracha do tipo não estocável (field blend) vem sendo bastante difundido nos Estados Unidos há décadas, principalmente no estado do Arizona. Este processo resulta em um asfalto-borracha de alta viscosidade, com alto desempenho, porém requer um equipamento de fabricação de asfalto-borracha específico, instalado no canteiro de obras, ou muito próximo à usina de asfaltos fornecedora da obra. Tendo em vista as possíveis vantagens tecnológicas do asfalto-borracha field blend e o conhecimento ainda pequeno sobre esta técnica no Brasil, há a necessidade de desenvolver estudos para a avaliação deste tipo de material frente às condições climáticas e de solicitação pelas cargas viárias em nosso país. Para tanto, foi realizado um estudo em laboratório para verificar as propriedades reológicas de um asfalto-borracha field blend e compará-las com as características de ligantes típicos empregados no Brasil (um CAP 30-45 e um ligante modificado por polímero elastomérico do tipo SBS). Elegeu-se o Multiple Stress Creep and Recovery (MSCR) para verificar a deformação permanente e o Time Sweep e Linear Amplitude Sweep (LAS) para verificar o comportamento na fadiga dos ligantes. Na sequência, determinou-se a deformação permanente e o comportamento à fadiga de uma mistura asfáltica descontínua (gap-graded) empregando o asfalto-borracha field blend em laboratório e no campo. A deformação permanente da mistura foi verificada por meio do simulador de tráfego LCPC, enquanto a vida de fadiga foi determinada utilizando o ensaio de flexão em viga (4 pontos). Por fim, foi construída uma seção teste após a conclusão da obra de restauração dos pavimentos da rodovia RJ-122, local onde se elegeu a utilização desta tecnologia pela primeira vez no país. O desempenho da mistura foi estudado in loco com o emprego de ensaios acelerados do pavimento utilizando-se o simulador de tráfego linear móvel em tamanho real. Os resultados obtidos foram utilizados para modelar o desempenho da estrutura com o revestimento asfáltico constituído pela mistura com o asfalto-borracha por meio dos modelos de trincamento e de deformação permanente do Highway Development and Management Model (HDM-4), podendo-se verificar o desempenho desta mistura calibrado para as condições locais. Os ensaios acelerados foram validados em campo por meio de campanhas de monitoramento periódicas realizadas ao longo de quatro anos na rodovia RJ-122. Pelos ensaios de laboratório no ligante e na mistura foi possível concluir que o asfalto-borracha field blend apresenta um bom desempenho quanto à deformação permanente e à fadiga, corroborando o que foi verificado no campo.
5

Field and laboratory performance evaluation of a field-blended rubber asphalt. / Avaliação de desempenho em campo e laboratório de um asfalto borracha field blend.

Felipe Filizzola Camargo 29 April 2016 (has links)
Rubber asphalt has been used in Brazil as early as 2001. Among the fabrication processes of rubber asphalt, the most widely used in Brazil is the terminal blend. However, the use of field-blended rubber asphalt has been around in the United States for decades, especially in the state of Arizona. This process results in a highly viscous material with enhanced engineering properties, but requires specific equipment that is typically installed at the job site, or close to the supplying asphalt plant. Thus, keeping in mind the possible technological advantages of using a field blended rubber asphalt mixture and the lack of information regarding this technique in Brazil, there is a necessity to develop studies to assess the performance of this type of material in our environmental conditions and axle loading configurations. Therefore, a laboratory study was conducted to determine the rheological properties of a field-blended rubber asphalt and compare them to those of typical binders used in Brazil (an AC 30/45 penetration grade and a binder modified with SBS, an elastomeric polymer). Binder permanent deformation was determined using the Multiple Stress Creep and Recovery (MSCR) test, whereas binder fatigue behavior was determined using the Time Sweep and Linear Amplitude Sweep (LAS) tests. Subsequently, the permanent deformation and fatigue behavior of a gap-graded mixture using the field-blended rubber asphalt were assessed in the laboratory and in the field. The permanent deformation of the mixture was determined in the laboratory using the LCPC wheel track test, whereas the fatigue behavior was determined using the four point bending flexural test. A test section was built after the rehabilitation job of highway RJ-122, where a field-blended rubber asphalt mixture was first used in the country. The mixture performance was studied in situ through accelerated pavement tests using a full scale, large mobile traffic simulator. The results were used to model the performance of the structure with the rubber asphalt mixture by means of the Highway Development and Management Model (HDM-4) cracking and permanent deformation models, calibrated to local conditions. Accelerated pavement tests were validated through periodic pavement monitoring campaigns conducted for four years in a test section in Highway RJ-122. The field-blended rubber asphalt showed a good performance in terms of permanent deformation and fatigue determined in the laboratory at the binder and mixture levels, which confirms what was verified in the field. / No Brasil, o asfalto-borracha vem sendo utilizado desde meados de 2001. Dentre os processos de fabricação do asfalto-borracha, o mais utilizado no Brasil é o asfalto-borracha estocável ou terminal blend. Contudo, o asfalto-borracha do tipo não estocável (field blend) vem sendo bastante difundido nos Estados Unidos há décadas, principalmente no estado do Arizona. Este processo resulta em um asfalto-borracha de alta viscosidade, com alto desempenho, porém requer um equipamento de fabricação de asfalto-borracha específico, instalado no canteiro de obras, ou muito próximo à usina de asfaltos fornecedora da obra. Tendo em vista as possíveis vantagens tecnológicas do asfalto-borracha field blend e o conhecimento ainda pequeno sobre esta técnica no Brasil, há a necessidade de desenvolver estudos para a avaliação deste tipo de material frente às condições climáticas e de solicitação pelas cargas viárias em nosso país. Para tanto, foi realizado um estudo em laboratório para verificar as propriedades reológicas de um asfalto-borracha field blend e compará-las com as características de ligantes típicos empregados no Brasil (um CAP 30-45 e um ligante modificado por polímero elastomérico do tipo SBS). Elegeu-se o Multiple Stress Creep and Recovery (MSCR) para verificar a deformação permanente e o Time Sweep e Linear Amplitude Sweep (LAS) para verificar o comportamento na fadiga dos ligantes. Na sequência, determinou-se a deformação permanente e o comportamento à fadiga de uma mistura asfáltica descontínua (gap-graded) empregando o asfalto-borracha field blend em laboratório e no campo. A deformação permanente da mistura foi verificada por meio do simulador de tráfego LCPC, enquanto a vida de fadiga foi determinada utilizando o ensaio de flexão em viga (4 pontos). Por fim, foi construída uma seção teste após a conclusão da obra de restauração dos pavimentos da rodovia RJ-122, local onde se elegeu a utilização desta tecnologia pela primeira vez no país. O desempenho da mistura foi estudado in loco com o emprego de ensaios acelerados do pavimento utilizando-se o simulador de tráfego linear móvel em tamanho real. Os resultados obtidos foram utilizados para modelar o desempenho da estrutura com o revestimento asfáltico constituído pela mistura com o asfalto-borracha por meio dos modelos de trincamento e de deformação permanente do Highway Development and Management Model (HDM-4), podendo-se verificar o desempenho desta mistura calibrado para as condições locais. Os ensaios acelerados foram validados em campo por meio de campanhas de monitoramento periódicas realizadas ao longo de quatro anos na rodovia RJ-122. Pelos ensaios de laboratório no ligante e na mistura foi possível concluir que o asfalto-borracha field blend apresenta um bom desempenho quanto à deformação permanente e à fadiga, corroborando o que foi verificado no campo.
6

Reduce, reuse, recycle & rethink assessing the sustainable and creative development of park furnishings for the Mill Creek Greenway Trail, Cincinnati, Ohio /

Hicks, Molly Erin. January 2007 (has links)
A practicum report for the degree of Master of Environmental Science, Institute of Environmental Sciences, Miami University, 2007. / Title from first page of PDF document. Includes bibliographical references (p. 63-73).
7

REDUCE, REUSE, RECYCLE & RETHINK: ASSESSING THE SUSTAINABLE AND CREATIVE DEVELOPMENT OF PARK FURNISHINGS FOR THE MILL CREEK GREENWAY TRAIL, CINCINNATI, OHIO

Hicks, Molly Erin 06 December 2007 (has links)
No description available.
8

Uplatnění pryžového granulátu v asfaltových pojivech a hutněných asfaltových směsích / Application of crumb rubber in bituminous binders and in bituminous mixtures

Dašek, Ondřej Unknown Date (has links)
Presented dissertation thesis is focused on the possibility of using the crumb rubber from waste tires for modification of paving grade bitumen. The resulting asphalt rubber can be used as an alternative to polymer modified bitumen in compacted bituminous mixtures. The theoretical part describes the rheological properties of asphalt binders and the history and today state of the art in the world and in the Czech Republic. The practical part of the work contains a description of the properties of chosen crumb rubbers and produced asphalt rubbers focused on their rheological properties and on change of these properties caused by the aging at high temperature. Subsequently, the chosen empirical and functional properties of bituminous mixtures with asphalt rubber are described. Laboratory properties of these mixtures were verified under real service conditions on 32 test sections. Based on the dissertation thesis results the preliminary technical specification of the Ministry of Transport (TP 148) and their following revision were approved. The conclusion of the work summarizes and highlights the results of the dissertation.

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