This masters thesis deals with influence of cement bypass kiln dust on physico-mechanical properties of alkali activated slag and influence of chosen compounds of cement bypass kiln dust on alkali activated slag. Using alkali activated slag is limited by its shrinkage. The setting time with different amount of cement bypass kiln dust and its chosen compounds (CaO, KCl and K2SO4) were measured by isotermal and isoperibolic calorimetry too. The strength and length changes of the mixtures with different amount of cement bypass kiln dust were measured. Samples were analysed by X-Ray diffraction analysis and scanning electron microscopy. It has been found that the increasing addition of dust reduce setting time, flexural and compresive strength and shrinkage. Presence of free CaO was found being one of the reasons for accelerated setting. KCl and K2SO4 have retarding effect but influece of free CaO prevails even for its lower contents. Long-term properties evolution is strongly dependent on curing regime due to potential volume expansion.

An investigation was conducted related to the dimensional stability of geosynthetic clay liners (GCLs) in landfill applications. Multiple occurrences of panel separation of overlap seams in GCLs have been documented; however, explanation for the relative contribution of various mechanisms causing shrinkage has been limited. A systematic test program was conducted to determine the effects of a variety of conditions on GCL dimensional stability. Effects of initial moisture content, permeant type, and overburden pressure were tested by subjecting various GCL products to wet-dry cycles and measuring the dimensional change with each cycle. Different GCL types were each tested under various combinations of initial moisture content (as-received, 50, 75, 100, and 125%), permeant types (tap water, distilled water, and 0.1 M CaCl2), and overburden pressures (0, 6, and 20 kPa). Thermal expansion tests were conducted by heating or cooling GCL test specimens to temperatures of 0, 10, 40, 60, and 80°C at constant moisture content. Subgrade tests were conducted by placing GCL test specimens on compacted clay and sand subgrades in different orientations and hydration conditions in sealed containers and measuring dimensional change over time. Mechanical necking tests were conducted by subjecting GCL specimens to varying levels of tension and measuring the longitudinal and transverse strains at each load increment. Field simulation tests were conducted by placing specimens on a compacted sand subgrade beneath an exposed geomembrane liner outdoors in late summer. Initial moisture content tests resulted in shrinkage strains as high as 20% after 20 wet-dry cycles. GCLs ranged from slightly anisotropic [approximately 1.1:1 ratio of machine (MD) to cross-machine (XMD) shrinkage] to highly anisotropic (approximately 3:1 ratio of MD to XMD shrinkage). Most combinations of GCL type and initial moisture content resulted in GCL MD shrinkage strains greater than a value that would cause panel separation (termed panel separation threshold, PST) at roll ends during the first wet-dry cycle. All test specimens contracted beyond the PST in the MD within 3 wet-dry cycles. GCL specimens without attached geomembranes contracted beyond the PST in the XMD within 5 cycles. Permeant type tests demonstrated that hydration with 0.1 M CaCl2 reduced shrinkage by 50-80% compared to permeation with tap water. Overburden tests demonstrated that applying 6 kPa and 20 kPa reduced specimen shrinkage by at least 60% and 80%, respectively. Thermal expansion tests indicated that temperature changes at constant moisture content had little effect on GCL dimensional stability. Subgrade tests demonstrated that subgrade type and moisture as well as GCL type and orientation had effects on dimensional stability. Tensile necking tests demonstrated that transverse shrinkage occurred due to tensile forces in GCLs, but shrinkage was nearly always less than PST. Field simulation tests demonstrated that wet-dry cycles in the field were less intense and/or less frequent than in the laboratory. Results of this testing provide a basis for GCL overlap specifications necessary to maintain full coverage and future research to confirm a suggested method of preconditioning bentonite to prevent shrinkage.

Master’s thesis deals with the design and assessment of the bearing structure of sewage treatment plant and development of the drawnings. The thesis solves the main part of the structure: base slabs, walls and ceiling slabs. Thesis solves the ultimate limit state and ultimate limit serviceability.

Combination of fine ground granulated slag with proper alkaline activator gives alkali-activated slag – a material with remarkable properties. Theoretical part of the thesis deals with summarizing basic informations about alkali-activated slag, its properties, production and utilization. It also follows research devoted to effects of curing of alkali activated slag and shrinkage-reducing admixtures on its properties. Objective of the experimental part is to determine the influence of curing conditions on the mechanical properties and microstructure of alkali-activated slag. These properties are also monitored in alkali-activated slag with carbon nanotubes and hydroxypropylmethylcellulose as an shrinkage-reducing admixtures.

This master thesis will cover the possibility of using directed gassing of Al-Si alloys in a high pressure die casting foundry. As a control gas, rotary degasser with gaseous 20 % H2 in N2 as a medium was used. Castings were casted via high pressure die casting machine. The aim of this research is to compare internal defect such as porosity or shrinkage of a casts made from degassed and control gassed melt.

The subject of dissertation is a study of physic-mechanical properties and development of self-leveling polymer-cement composite of the ternary binder system PC-CAC-CS modified with chemical additives and polymeric substances. The dissertation systematically describes a four-step optimalization of the composite considering its key properties. Experimental part has been focused on monitoring the impact of composite components on selected final properties. Basic physico-mechanical, structural properties and its relations (compressive strength, porosity, flow abilities, setting times) have been analyzed for deeper understanding of the effects of individual composite components. Methods which quantify the existence of the newly formed hydration product – ettringite (XRD, SEM with EDS, calorimetry, dilatometry) has been chosen as additional study methods on selected combinations. A working prototype of self-leveling polymer-cement composite was successfully developed based on systematic process and using of testing procedures and measuring methods.

The diploma thesis deals with the issue of waterproof concrete and testing its properties. The theoretical part is conceived through research on existing knowledge relating to waterproof concrete. Emphasis is placed on the possibility of using a waterproof concrete for structures, such is e.g. tunnel lining. The experimental part is focused on the laboratory testing of waterproof concrete. Particulary examined was the effect of various admixtures as a partial replacement of cement. Monitored was the development of compressive strength and flexural strength, development of temperature during hydration in the early stages of maturation of concrete, water resistance of concrete, concrete surface resistance to water and chemical de-icing agents, as well as development of shrinkage during concrete maturation.

Riga has suffered a population loss of more than 29% between 1990 and 2014 which has led to increasing number of abandoned and degraded buildings in the city and optimization of the network of educational and cultural institutions. These trends are characteristics of urban shrinkage – a complex process affecting Riga for more than two decades and resulting in a pattern of growing, shrinking, and stable districts. A similar pattern has also been identified in other shrinking cities in Europe, but it has not been researched in more detail. In the given context, this research aims to narrow the knowledge gap on processes occurring in shrinking cities and to provide some understanding of the determinants of these processes on the city and local level through analysis of single embedded case study of Riga. To achieve this aim, resilience is used as an analytical concept. It allows to conceptualize urban shrinkage as a slow-burn (slowly occurring disturbance) and propose three possible responses - adaptation, transformation, and decline. These responses emerge from actions of actors on various spatial scales and lead to different outcomes. It also provides the basis for analyzing the determinants of these responses by conceptualizing them as sources of resilience and suggesting seven different aspects found in literature: leadership, networks, resources, learning, people-place connection, common cause, and system of institutions and governance. Finally, these theoretical assumptions are used to define two main research questions: (1) what are responses to urban shrinkage in Riga? (2) what are sources of resilience to urban shrinkage in Riga? The need for in-depth research of urban processes led to choosing mixed method strategy for both selecting the embedded units of analysis (districts) in Riga and finding answers to the proposed research questions. Based on combined results of secondary data analysis, controlled expert group discussion, and structured site visits, five districts in Riga were selected – Avoti, Maskavas forštate, Bolderāja, Sarkandaugava, and Ķīpsala. Further data collection and analysis included semi-structured interviews with different actors at the city and district level and document analysis. The study finds that there are four different responses to urban shrinkage in Riga: mitigation, adaptation, transformation, and possible decline. Mitigation can be identified on city (also national) level and is closely linked with the strategic actions proposed by the local and national government in response to population decline. Adaptation can be observed on the city and local level. It is the dominant response type in Riga emerging from strategic actions and different activities by various actors in response to all of the identified processes associated with urban shrinkage in Riga. Transformation, however, can be found only on local level – district (in one specific case) or unit level. It emerges from activities of mostly non-government actors that are making use of the opportunities provided by urban shrinkage in Riga. Finally, further decline is a potential response in several Riga districts resulting from strategic actions of local municipality and inability of some of the actors to deal with the existing situation. The analysis of sources of resilience reveals that there are four main determinants of adaptation and transformation – leadership, networks, resources, and learning. Other sources of resilience (people-place connection, common cause, and engaged governance) function as additional drivers or catalysts. All of these sources of resilience can be identified in Riga, but not consistently across all spatial scales and units or actor groups. The main deficiencies are linked with availability of resources (human and financial) among different actor groups, the existing system of governance (involvement of actors in the decision-making process) and leadership (on city level). The study also shows differences related to responses to urban shrinkage and different sources of resilience, especially leadership, learning, and resources. Overall, the findings support the main theoretical assumptions of the study and allow refining the understanding of responses to urban shrinkage and sources of resilience. The results can be used as the basis for developing an approach for assessment of the level of resilience to urban shrinkage or other slow burns in the urban context.

The diploma thesis is a case study of the outflow of young people from the town of Šumperk. The aim of this work is to explain the main causes of the problem, to determine the extent to which suburbanization is involved in the process, to evaluate the town's existing policies to solve the problem and to suggest possible solutions. The research is based on the theoretical concepts of the public policy cycle, which helps to determine the stage at which the problem is at the town level, works with the theory of city shrinkage, the theory of suburbanization, and push-pull migration theory. The original research is based on data from sociological research and interviews. Conclusions of the thesis include the finding that the main causes of the outflow of young people are inadequate job opportunities for college students and poor housing offers. Suburbanisation also contributes to the process of shrinking. The town's current policy lacks a strategic concept that would prevent the outflow. In conclusion, the author suggests possible partial solutions to the problem, such as creation of a coworking center or a change in the zone planning strategy.

Gamla Årstabron i Stockholm uppvisade efter 80 år i drift omfattande skador på de bärande betongkonstruktionerna enligt en utredning som genomfördes 2006 av dåvarande Carl Bro AB på uppdrag av dåvarande Banverket Region Öst. Det konstaterades att omfattande reparationer och förstärkningar av brons betongvalv var nödvändiga för framtida rationell drift av bron. Det beslutades efter vidare utredning att de första tre valven på Södermalm i Stockholm skulle renoveras med injekteringsbetong. Renoveringen av de tre valven på fastlandet på Södermalm var ett prov i full skala för att hitta den optimala metodiken för den fortsatta renoveringen av resterande 17 betongvalv. Det här examensarbetet syftar till att utvärdera metoden med injekteringsbetong med hänsyn till injekteringsbetongens egenskaper, material och produktionsteknik.   Bakgrunden till detta examensarbete är att det finns ett stort behov av att följa upp renoveringsmetoden med injekteringsbetong eftersom den inte har använts i någon större utsträckning i Sverige sedan slutet av 1970-talet. Utvärderingen av injekteringsbetongens egenskaper har utförts genom att analysera resultaten av de provningar som utförts på betongen. Provningen har gått till så att utborrade kärnor och tillverkade provkuber har provats för bland annat tryck- och draghållfasthet (vidhäftning). Utvärderingen av material och produktionsteknik har gjorts genom observationer på arbetsplatsen där rapportförfattaren praktiserade hos NCC under juni och augusti 2008. Utöver praktiken har jag närvarat vid och dokumenterat många av de injekteringar som gjorts under projektets första år.   Huvudsyftet med att använda injekteringsbetong var att få fram en betong som uppvisar tillräckligt hög tryckhållfasthet, en viss draghållfasthet och en fri krympning av högst 0,2 ‰. Tyvärr var inte provtagningen tillräckligt omfattande för att dra statistiskt säkerställda slutsatser gällande betongens egenskaper. Det som dock kan sägas är att provtagningen samt information från nyckelpersoner från beställaren (numera Trafikverket) tenderar att bekräfta det som konstaterats i de förstudier som gjordes innan brorenoveringen startade, nämligen att injekteringsbetongen uppvisar en klart lägre krympning än konventionellt gjuten brobetong. Vad gäller tryck- och draghållfasthet så uppfyller den färdiga betongen de krav som ställdes.   Blandning av ingående material i form av ballast och cementbruk samt de enskilda materialens egenskaper visade sig vara en kritisk punkt, vilket bekräftar det som framgår av litteraturen på området. Att kravet på renhet hos ballasten, stenmaterialet, är uppfyllt är av yttersta vikt för slutresultatet. Dessutom är det mycket viktigt att cementbruket som blandas med vatten precis innan det injekteras i den stenfyllda formen håller mycket hög kvalité och är stabilt. I vissa aspekter ställer också metoden högre krav på yrkesarbetare, platsledning och övrig produktionspersonal som pumpförare jämfört med att gjuta med konventionell betong. Förutom de enskilda gruppernas kompetens är också samordningen och logistiken på arbetsplatsen en mycket viktig faktor. Att använda metoden innebär dessutom att beställare och specialister måste ha kunskap och förståelse för att metoden ur vissa synvinklar skiljer från konventionell betong, särskild med tanke på den begränsade användningen av metoden i Sverige i modern tid.   Baserat på slutresultatet av renoveringen, de provningar som utförts samt omdömen från nyckelpersoner hos beställaren var injekteringsbetong rätt metod att använda för att renovera Gamla Årstabron. / According to an investigation conducted in 2006 by the former Carl Bro AB commissioned by the former Swedish railway authority (Banverket), the old Årsta bridge in Stockholm, Sweden, was  after 80 years in operation showing signs of extensive damage on the load-bearing concrete structures. It was pointed out that the concrete vaults of the bridge needed to be repaired and reinforced in order to keep the bridge in an operational state. After further investigation it was decided that the first three vaults on the north side of the bridge were to be renovated by using pre-placed aggregate concrete. The renovation of the three vaults on the north side served as a full-scale test to find the best possible methodology for the continued renovation of the concrete structures that consists of another seventeen concrete vaults. This thesis aims to evaluate the method of using pre-placed aggregate concrete regarding its properties and materials as well as the construction technology.   The reason for this thesis is that there is a great need to follow up the renovation method using pre-placed aggregate concrete since it hasn’t been used in any great extent in Sweden since late 1970’s.The evaluation of the concrete’s properties has been done by analyzing the results of the testing that has been performed on the concrete. Test specimens consisting of concrete cores and fabricated cubes have been tested for compressive and tensile (bond) strength. The evaluation of materials and construction technology has been done by practical observations on the work site where the author worked as an intern for the contractor NCC during June and August 2008. Apart from my internship I also attended and documented many of the grouting occasions during the first year of the project.   The main intention of using pre-placed aggregate concrete was to produce a concrete with high compressive strength, certain tensile strength and a free shrinkage of at most 0,2 ‰. The testing of the concrete was unfortunately not extensive enough to draw any unambiguous conclusions concerning the properties of the concrete. The results of the tests performed as well as information from key persons from the current Swedish traffic administration (Trafikverket) do however tend to confirm what was found during the pilot studies conducted before the renovation of the bridge started, namely that the pre-placed aggregate concrete has a much lower shrinkage than conventional concrete normally used in bridges. As for compressive and tensile strength, the pre-placed aggregate concrete meets the quality requirements.    The mix of included materials, aggregate and cement-based grout, as well as the properties of the materials themselves turned out to be critical for the result, which the literature in the field confirms. The purity of the aggregate is essential for the result. Moreover, it’s very important that the cement-based grout is of high quality and stable. When comparing with traditional concreting, the method imposes higher requirements on the workforce, management and subcontractors, in some aspects. Two other key factors, apart from the competence of each group, are the coordination and the logistics on the worksite. Using pre-placed aggregate concrete also implies that clients and specialists must have knowledge and understanding concerning the differences compared to traditional concreting, especially since the method hasn’t been used in any greater extent in Sweden the last 40 years.   Based on the result of renovation, tests conducted and reviews from key persons at the Swedish transport administration the decision to use pre-placed aggregate concrete was the right one.