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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.
21

Problematika stárnutí asfaltových pojiv a směsí / Ageing of asphalt binders and mixtures

Štěpanovský, Vlastimil January 2015 (has links)
Diploma thesis is particularly focused on ageing of asphalt mixtures and asphalt binders. In the theoretical part an array of methods simulating short term and long term ageing consequently is introduced. The main objective of the practical part was to carry out the long-term ageing test method BSA (Braunschweiger Alterung). Thereafter, specimens testing for stiffness properties according to CSN EN 12697-26 were made. After conducting the measurement on those, asphalt binder was extracted and processed to follow-up testing. The testing consisted of a range of methods – Penetration CSN EN 1426, Ring and Ball test CSN EN 1427, Determination of the Frass breaking point CSN EN 12593, Determination of complex shear modulus CSN EN 14770 and Dynamic viscosity using a dynamic shear rheometer (DSR). The given results were assessed in the last part in order to evaluate the rate of the binder degradation caused by the method BSA.
22

Relaxace smykového napětí asfaltových pojiv v DSR / Shear stress relaxation of bituminous binders in DSR

Musil, Vladimír January 2015 (has links)
The thesis describes the relaxation properties of bituminous binders determined in dynamic shear rheometer (DSR). Paving bitumen, polymer modified bitumen (PMB) and crumb rubber modified bitumen (CRmB) were chosen for comparison. In order to describe the effects of ageing on asphalt binders relaxation properties, the laboratory simulation of ageing using RTFOT and 3xRTFOT method was performed. For each binder were simultaneously conducted tests of needle penetration, softening point and elastic recovery. Selected bitumens were used for the production of asphalt mixtures. The low-temperature properties tests (TSRST) were performed for these mixtures, when the results were compared to the relaxation properties of binders determined in the DSR.
23

Stárnutí asfaltových pojiv / Ageing of asphalt binders

Střasáková, Monika January 2016 (has links)
The theoretical part of this thesis describes the rheology of bituminous binders, aging of asphalt binders and laboratory methods simulating short and long term aging. The following describes an empirical tests (needle penetration, softening point ring ball method) and functional tests (complex shear modulus and phase angle, dynamic viscosity), which are performed in the dynamic shear rheometer. At the end of this section, laboratory aging of bituminous binders using method RTFOT and method RTFOT + PAV is described in more detail. In the practical part of this thesis, the results of all tests performed on the binders aged using RTFOT + PAV are introduced and compared with results of properties of non-aged binders and binders aged by 3xRTFOT.
24

Využití přísady vhodné pro dodatečnou modifikaci asfaltové směsi / Use of an additive suitable for additional modification of the asphalt mixture

Machová, Sára January 2022 (has links)
This thesis deals with the modification of asphalt binder 50/70 with fast reacting SBS. This is a relatively new additive that should be able to improve the binder properties during mixing of the asphalt mix at the plant. In the theoretical part, the issue of asphalt-mixing plant and polymer modification additives is presented. Furthermore, the test methods used such as needle penetration, softening point, determination of the elastic recovery, DSR and MSCR are described. Several modified binder samples were developed for the tests, in which mixing temperature, mixing time and SBS content were combined. The results of each test were compared and evaluated at the end of the thesis.
25

Možnosti mísení pojiv typu PMB RC s pojivem z R-materiálu / Possibility of mixing PMB RC type binders with reclaimed binder from RAP

Trnka, Lukáš Unknown Date (has links)
The diploma thesis deals with the possibility of mixing binders of the PMB RC type with a binder made of reclaimed ashalt. lists the types of asphalt binders, its production and modification are in the teoretical part. There is explained the principle of rejuvenators function, types of rejuvenators. The procedures for performing tests on asphalt binders: recovery of asphalt binder, needle penetration, softening point (ring and ball method), reversible ductility, breaking point (according to Fraass) and DSR. Individual tests are evaluated and asphalt mixtures are compared in the practical part of asphalt binder. The diploma thesis deals with the possibility of mixing binders of the PMB RC type with a binder made of reclaimed ashalt. lists the types of asphalt binders, its production and modification are in the teoretical part. There is explained the principle of rejuvenators function, types of rejuvenators. The procedures for performing tests on asphalt binders: recovery of asphalt binder, needle penetration, softening point (ring and ball method), reversible ductility, breaking point (according to Fraass) and DSR. Individual tests are evaluated and asphalt mixtures are compared in the practical part of asphalt binder.
26

Dávkování oživovacích přísad do asfaltové směsi s vysokým obsahem R-materiálu / Dosage of rejuvenating agents to asphalt mixture with high content of RAP

Čumíčková, Markéta January 2019 (has links)
The diploma thesis is focused on the appropriate dosage of rejuvenating agents in asphalt mixtures with high content of RAP. The empirical and functional laboratory tests are described in the theoretical part. The practical part deals with the estimation of the optimal amount of rejuvenating agents by means of laboratory tests so that the rheological properties of the degraded asphalt binder can be restored by suitable dosing into the RAP. As part of the TAČR ZÉTA project, an experimental section of asphalt mixture containing 50 % of the RAP and an appropriate amount of the rejuvenating agents was created. The aim of the thesis is to find an optimal dosage of the rejuvenating agents in the samples of the RAP and laboratory aged asphalt binder of gradation 50/70, to determine the effectiveness of selected rejuvenating agents and to monitor changes in the parameters of the experimental section during the period of time.
27

Využití fluxačních přísad pro úpravu vlastností asfaltových pojiv / Use of fluxing additives to modify the properties of asphalt binders

Šefránková, Radka January 2020 (has links)
The subject of the thesis is to describe the effect of fluxing additives on the behaviour of asphalt binders. Emphasis will be placed on changes in rheological properties of asphalt binders at intermediate temperatures, stability during aging and influence of fluxing agents on their low-temperature properties. Theoretical part will deal with the principle of asphalt binders aging and it will summarize knowledge about fluxing additives. Further, empirical and functional tests will be described in order to evaluate asphalt binders. In the practical part, all laboratory tests will be evaluated and the effects of two different fluxing additives will be compared.
28

Návrh asfaltových směsí typu SAL určených pro opravu cementobetonových krytů / Design of SAL asphalt mixtures for rehabilitation of concrete pavements

Vlk, Radomír January 2015 (has links)
This master's thesis describes how to use the asphalt layer called Stress Absorbing Layer (SAL) and comparises it with other types of SAL with different types of asphalt binders. In the first theoretical part is SAL generally described. In the second part is SAL practically tested and described.
29

Optimalizace technologie výroby odlitků ze slitin Al metodou vytavitelného modelu / Optimized manufacturing of aluminium castings by using lost wax technology

Talanda, Ivan January 2012 (has links)
Aim of this diploma thesis is to choose new pattern wax for Fimes a.s. foundry. New wax should substitute old not fully satisfactory pattern wax which caused problems in technological process resulting in increased number of rejects. New pattern wax should eliminate current problems and help foundry with producing large, thin-walled, high-quality castings. Numbers of pattern waxes supplied by world’s leading wax manufacturers were subjected to laboratory tests and pilot study. This diploma thesis is part of project Alfa TA01010766: „Research and development of production technology large, thin and high quality castings of aluminium alloys “
30

Hodnocení vlastností pojiv typu PMB obsahujících pojivo z R-materiálu / Evaluation of properties of PMB containing binder from RAP

Měšťanová, Petra Unknown Date (has links)
Subject of this diploma thesis is to describe the effect of adding different amount of aged binder recovered from RAP on the change of properties of polymer modified bitumen. The RAP containing unmodified bitumen and the RAP where we can expect bitumen modification are used to recover binder. The binder obtained from RAP is dosed into the virgin binder in amount of 15 %, 30 % and 50 %. The methods of recycling of flexible pavements, extraction and regeneration of asphalt binders, rejuvenating of their properties and methods of empirical and functional laboratory tests are described in the theoretical part. The practical part deals with evaluating and comparison of the results mixed binders properties.

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