abstract: This research focused on the structure-property relationships of a rejuvenator to understand the comprehensive rejuvenation mechanism of aged asphalt binder. Aged asphalt such as recycled asphalt shingles (RAS) and reclaimed asphalt pavement (RAP) contain various amounts of asphalt binder. However, the asphalt binder in RAS and RAP is severely aged and inferior in properties compared to a virgin binder. To address this issue, liquid additives have been used under the general title of rejuvenators. That poses an additional challenge associated with the lack of clear metrics to differentiate between softeners and rejuvenators. Therefore, there is a need for a thorough study of rejuvenators. In this study, diverse-sourced rejuvenators have been used in RAS and RAP-modified binders as well as laboratory-prepared aged binders. The properties of the rejuvenated aged binder were characterized at a macro-level and molecular level. The study showed that the performance of the RAS-modified binder was significantly improved after bio-modification by a bio-rejuvenator. This study further evaluated laboratory-prepared aged asphalt rejuvenated with different rejuvenators. The results found that oxidized bitumen became soft after adding rejuvenators, regardless of their source. Molecular dynamics simulation showed that the effective rejuvenator restored the molecular conformation and reduced the size of asphaltene nanoaggregates. The study results showed that due to the specific chemical composition of certain rejuvenators, they may negatively impact the durability of the mixture, especially about its resistance to moisture damage and aging. Computational analysis showed that while the restoration capacity of rejuvenators is related to their penetration into and peptizing of asphaltene nanoaggregates, the durability of the restored aged asphalt is mainly related to the polarizability values of the rejuvenator. Rejuvenators with lower polarizability showed better resistance to aging and moisture damage. In summary, this study develops the rheology-based indicators which relate to the molecular level phenomenon in the rejuvenation mechanism. The rheology-based indicators, for instance, crossover modulus and crossover frequency differentiated the rejuvenators from recycling agents. Moreover, the study found that rejuvenation efficiency and durability are depended on the chemistry of rejuvenators. Finally, based on the learning of chemistry, a chemically balanced rejuvenator is synthesized with superior rejuvenation properties. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2020

京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13328号 / 論医博第2196号 / 新制||医||1044(附属図書館) / (主査)教授 柳田 素子, 教授 佐藤 俊哉, 教授 長船 健二 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

Background – Design for longevity stand in strong contrast to the dominant model of fast fashion, where mass-production, low prices and poor quality is the characteristics. The fast-paced model is linked to environmental degradation and there is a need for a systemic change in the system. Design for longevity has been identified as one of the most effective means to reduce environmental impacts, however there are significant gaps in knowledge in relation to garment longevity and its integration within fashion brands. As the active lifetimes of garments are decreasing, resulting in a truck full of textiles and clothing reaching landfill evert second (EllenMacArthurFoundation 2017). This shows that consumers have fleeting relationships with their garment and product attachment has decreased, which shows that there is a need for strategies that facilitate product attachment to help facilitate more circularity within textiles and clothing. Emotional durability has been highlighted as an approach to design for longevity, it’s a new research area that tries to understand the complex interchange between consumption, the meaning of products and relationships between people and products. Emotional durability focuses on ways to prolong the use of products to extend the lifetimes and thereby decreasing the need for early garment replacement.  Purpose – This study focuses on understanding the phenomenon of emotional durability and its integration possibilities in textiles and clothing companies. The purpose for this thesis is to expand on current knowledge on emotional durability from a brand perspective, through highlighting the challenges and enablers for emotional durability. Using design thinking to understand it’s integration potential, through collaboration and iterative feedback loops to push innovation and build resilience into product-user relationships.  Methodology – The research was conducted using a single case study with an abductive approach. The research builds on the theoretical perspective of IDEO (nd) design thinking theory. Semi-structured interviews with a Swedish fashion and lifestyle company, including employees within the design, sustainability, quality and communications departments provided the basis for collecting primary data. The primary data was supplemented with secondary data which included website articles, sustainability reports and internal documents. The data was analysed qualitatively through thematic content analysis which was triangulated.  Findings – The results of the study, shows that emotional durability can be enabled through a range of strategies including personalisation, transparency, graceful ageing, functionality. These strategies can be supported by services provided by brands, where communicative education plays a supporting role in helping build relationship which can ensure better product retention. The results further highlighted that using design thinking theory can help overcome some of the challenges that was found within emotional durability. Through continuous collaboration both across departments, but also with stakeholders and competitors a knowledge sharing platform can be built, which can ensure better opportunities within emotional durability and thereby designing for longevity.  Practical implications and research limitations - This research contributes to creating new insight into a relatively unexplored area, emotional durability from a brand perspective and the integration through the use of strategies and services. Thus, aiding brands to gain more understanding in the integration and thereby providing solutions that can facilitate longevity. The study is limited by the choice of case-company, which is a Swedish Fashion and lifestyle company.

This diploma thesis deals with concrete abrasion resistance against abrasion. The constructions of transport and water management structures are most stressed by the action of abrasion by means of travel of vehicles and flowing water. Abrasion reduces the durability of the structures. The prerequisites for achieving the best possible abrasion resistance are examined. Furthermore, test methods that are currently used worldwide. The experimental part deals with the influence of individual types of aggregates amphibolite (Želešice), fecal gravel sand (Žabčice) and basalt (Bílčice) on abrasion resistance. Furthermore, the dependence between the strength of the concrete and the hardness of the surface for abrasion resistance. Abrasion resistance testing was determined by concrete abrasion, abrasion resistance by the Böhm method and by water jet.

Alkali activated binders have the potential to become an alternative construction material to ordinary portland cement binders. This thesis concentrates on durability testing of alkali activated blast furnace slag and fly ash based concrete. The chosen aspects of durability included sulfate resistance, acid resistance, carbonation, freeze-thaw resistance, frost-salt resistance and porosity. Microstructural changes and formation of new crystalline phases were observed using XRD and SEM-EDX analysis. Potential application of the tested material from the durability point of view was evaluated by comparison with a reference ordinary portland cement based concrete.

This master´s thesis studies qualities of aerated concretes, is monitoring influenece concrete composition, quantity of aerating admixture and plasticized admixture on the durability of concrete. It is monitored especially air flow and his influence on durability on concrete. In theoretical part are explained mechanisms of damage concrete, phenomena, which influence compressive strength of concrete and then there are the results of resistance against the influence of chemical defrosting substances. In experimental work were designed, mixed and tested recipe of concerete. We investigated different atribute, especially resistance of the chemical defrosting and air flow in hardened concrete. The result of master´s thesis is effect of flow air in concrete on the durability.

Refractory mastics are used for making compact brickworks or for sealing up the joints. This thesis deals with lenghthening of best before date of Regnaterm mastic, modification of recipe and suggestion of suitable method for evaluating reologic characteristics.

Fly ash is now much used as an admixture to concrete. This master´s thesis focuses on the use of fly ash as an active admixture in concrete environment for XF. The thesis has two parts. The first part collected theoretical information about the origin and behavior of fly ash in fresh and hardened concrete. In the second part was experimental verification of these characteristics. The purpouse of this thesis is to demonstrate that the fly ash attribute to meet all environmental XF.

The master`s thesis deal with analysis of machining technology of the bolt from the superalloy Ni80TiAl for the company Sanborn a.s. The aim of the thesis is the project of new technology by usage of new tool, indexable inserts and cutting conditions. The results are speedup of the roughing operation, reduction of the manufacturing cost and the product price.

Diploma work describes speed drill steels and its qualities before and after coating by methods PVD (Physical Vapour Deposition). The theoretic part is concerned with thermic processing of speed drill steels and their qualities with regard to individual alloying elements contained and its mechanical features. Second part of the theoretic part is concerned with particular methods of coating by the help of PVD technologies, kinds of coating with regard to additional elements and their qualities and surface treatments of coated material before and after its coating. The goal of the experimental part was the confrontation of cutting power features of cylindrical four-fluted face mills with straight shank, from speed drill steels non-coated and coated in two basic modes of milling – down-feed method and upfeed method. The results of measurements were interpreted by the help of four basic pictures (source values, power analysis, specific values). The result of all the experiment is that the application of PVD coatings enabled the increasing of cutting speed (with preservation of other cutting requirements) and led to decreasing of cutting force and cutting enforcements and extended durability of cutters.