National Repository of Grey Literature 12 records found  1 - 10next  jump to record: Search took 0.01 seconds. 
Use of fluxing additives to modify the properties of asphalt binders
Šefránková, Radka ; Koudelka, Tomáš (referee) ; Dašek, Ondřej (advisor)
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.
Influence of
Dostál, Filip ; Dašek, Ondřej (referee) ; Hýzl, Petr (advisor)
The diploma thesis is focused on polymer modified binders with different polymer doses. The theoretical part describes the history of the use of bitumen, the extraction of bitumen from oil and behavious of the polymer type SBS/SB, which is used in the diploma thesis on modified binders. Further, the theoretical part describes the empirical and functional tests of bitumen binders. In the practical part the results of indidual tests are presented and compared with the standard ČSN 65 7222-1. At the end of the diploma thesis are summarized results of work and evaluation of binders with the best achieved properties.
Dosage of rejuvenating agents to asphalt mixture with high content of RAP
Čumíčková, Markéta ; Coufalíková, Iva (referee) ; Dašek, Ondřej (advisor)
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.
Properties of polymer modified bitumen for warm mix asphalt
Zábranský, Ivo ; Koudelka, Tomáš (referee) ; Dašek, Ondřej (advisor)
The Diploma thesis is focus on polymer modified bitumen for warm mix asphalt. The theoretical part of the thesis describes additives which influence the properties of bitumen for their use and reduction of production and service temperatures. Further, the theoretical part describes the conclusions from the researches. This part also describes empirical and functional tests of bituminous binders. The practical part presents the results of individual tests. Tests were performed on samples of non-aged, aged by RTFOT and RTFOT + PAV methods. The results of the work and the assessment of the suitability of bituminous binders are summarized at the end of the thesis.
Nutritional problems in patients with chronic graft-versus-host disease after allogeneic transplantation of hematopoietic cells
Michková, Petra ; Šťastná-Marková, Markéta (advisor) ; Novák, František (referee)
Introduction: Graft versus host disease (GVHD) is a serious medical complication following allogeneic hematopoietic cell transplantation (allo HSCT). It causes immunodeficiency and several organ damage and decreases survival time at two years after a transplantation. A nutritional intervention should be applied just before the transplantation, because a nutritional status significantly influences the post-transplant complications. A risk of malnutrition or metabolic syndrome can be assessed by several markers. A combination of laboratory, anthropometric, biometric and physical data is suitable for this purpose. In addition, a subjective questionnaire regarding eating habits and physical activity of the patients can be used. Objectives: This thesis deals with the patients with chronic GVHD (cGVHD) following the allo HSCT. The objective was to describe a nutritional status of the patients, to find out in which way a long-term immunosuppressive treatment affects a body composition and to describe the eating habits and the physical activity of these patients. Methods: 31 patients with GVHD and 24 patients after allo HSCT without GVHD participated in the research. A body composition (using bioelectrical impedance) and selected laboratory parameters in patients were assessed. A subjective health...
Interaction between asphalt binder and filler
Indráková, Kristýna ; Hýzl, Petr (referee) ; Dašek, Ondřej (advisor)
The thesis is mainly focused on comparison of properties of mastics, that were mixed in lab. The samples of mastics were mixed of paving bitumen in combination with 9 samples of backhouse filler, 1 inappropriate sample containing mica and 1 sample of additive filler. The folowing tests were used for assessment of samples: The particle density of filler-pyknometer method, The delta ring and ball test, The complex shear modulus and phase angle, The multiple stress creep and recovery test. The tests results were evaluated and compared. The results of the thesis are listed in the conclusion.
Stone mastic asphalts with recycled materials - bituminous binders properties
Dzurková, Veronika ; Coufalíková, Iva (referee) ; Hýzl, Petr (advisor)
The bachelor thesis is focused on the issue of adding R-material to stone mastic asphalt mixtures (SMA). The material was obtained from a plant that put the mixture in the test section on the road II/227. The theoretical part describes the problems of recycling of asphalt roads, bituminal binder theory and problems associated with the addition of R-material to hot asphalt mixtures. Bituminal binders from mixtures with different percentages of R-material were extracted in the practical part. Empirical and functional tests were performed on these binders. The aim of the thesis is to determine the influence of the presence of R-material on SMA asphalt mixture in terms of properties of asphalt binder.
Rheological properties of asphalt binders
Coufalík, Pavel ; Bačová,, Katarína (referee) ; Komačka,, Jozef (referee) ; Hýzl, Petr (advisor)
Dissertation thesis is focused on rheological properties of asphalt binders and on changes of their performance during the lifetime in road structures. Aging processes of asphalt binders and methods of laboratory aging are described in the theoretical part of the thesis. Furthermore, basic rheological models and related test methods for the evaluation of asphalt binders are described. In the practical part, properties of asphalt binders are investigated after aging process and their performance is evaluated by empirical and functional test methods. The various methods of aging are compared with each other and a relationship between real conditions and laboratory aging is researched. In the next section, vacuum flashed cracked residue (VFCR) is added to the selected asphalt binders and their influence on rheological properties during description of aging of asphalt binders is investigated. The results were used in publication of two certified methodology under the title „The methodology for the evaluation of paving bitumen in terms of susceptibility to thermal oxidative aging“ and „The methodology describes laboratory aging of asphalt mixtures“. The results of the thesis are listed in the conclusion.
Ageing of asphalt binders
Střasáková, Monika ; Hegr, Zdeněk (referee) ; Dašek, Ondřej (advisor)
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.
Rheological properties of asphalt binders
Pěnčík, Michal ; Mondschein,, Petr (referee) ; Hýzl, Petr (advisor)
The Diploma thesis is focused on rheological properties of bituminous binders and mixtures. Above all, it describes the changes of these properties of samples of bituminous binders and mixtures. Those were brought by the process of laboratory aging, since it simulates the changes occurring in the in the real-life conditions. The theoretical part depicts the field of rheology and methods utilized for simulating the ageing of binders and mixtures. The practical part describes the process of preparation of samples and its testing. Firstly, the ageing of bituminous mixture by the means of BSA method (Braunschweiger Alterung) took place, which was followed by preparing the solids for testing the modulus of stiffness and main testing. The rest of the mixture was used for extracting the binder. Tests with the binder were focused on the usage of dynamic shear rheometer (complex shear modulus, dynamic viscosity). The last part of the work is dedicated to the comparison of the outcomes of testing.

National Repository of Grey Literature : 12 records found   1 - 10next  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.