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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.
161

Daugiabučių namų atnaujinimo programos įgyvendinimo Lietuvoje tyrimas / The Research of Renovation Program of Multistory Buildings Implemention in Lithuania

Ropaitė, Guoda 23 July 2012 (has links)
Baigiamajame magistro darbe nagrinėjama Daugiabučių namų atnaujinimo programa, atliekama jos įgyvendinimo Lietuvoje analizė, siekiant identifikuoti pagrindines problemas, bei pateikiami pasiūlymus dėl jų sprendimo. Taip pat apžvelgiamas Lietuvos būsto fondas, analizuojama užsienio šalių patirtis daugiabučių namų modernizavimo srityje bei atliekama 2010 m. modernizavimo programoje dalyvavusių atnaujintų daugiabučių namų analizę, apskaičiuojant panaudotų energiją taupančių modernizavimo priemonių investicinį efektyvumą energetiniu požiūriu. Darbą sudaro 4 dalys: įvadas, analitinė dalis, apimanti Lietuvos būsto sektoriaus apžvalgą, Daugiabučių namų modernizavimo programos analizę ir užsienio šalių patirtį daugiabučių namų atnaujinimo srityje, tiriamoji dalis – Lietuvos miestuose renovuotų daugiabučių analizę, išvados ir pasiūlymai, literatūros sąrašas bei priedai. Darbo apimtis – 97 p. teksto be priedų, 23 iliustr., 14 lent., 67 bibliografiniai šaltiniai. Atskirai pridedami darbo priedai. / The master thesis analizes the blocks of flats renovation programme, indentifies the main problems in implementing the programme and lists offers for its solution. Also are carried out the overview of the housing stock in Lithuania and analyzed foreing countries experience in modernization of the blocks of flats. The research of blocks of flats which 2010 participate in the modernization programme are carried out calculating the energy-saving modernization measures in terms of energy efficiency investment. This thesis consist of four parts: an introduction, the analytical part which includes the Lithuanian housing sector review, the blocks of flats modernization programme analysis and foreing countries experience in modernization of the blocks of flats, the research part – the analysis of foreing experience in modernization of the blocks of flats, a conclusion and recommendations, a reference and annexes. Thesis contains 97 pages of text (without annexes). There are 23 figures, 14 tables, 67 bibliographical sources. Appendixes included.
162

La finance comportementale à l'épreuve de la crise / Behavioral finance under the test of the crisis

Hajji, Ali 11 December 2015 (has links)
La crise qui a démarré en 2007 a remis en cause les fondations de la théorie et du système financier. Cette théorie s’articule autour des postulats de la finance classique dont la « main invisible » et l’hypothèse de rationalité des investisseurs dont découle celle d’efficience des marchés.Cette crise a mis en lumière l’aspect psychologique des marchés financiers, aspect abordé par J.M Keynes lorsqu’il développait la notion d’ « esprits animaux » pour rendre compte de l’incertitude de l’économie. Jusqu’au début des années 1980, la compréhension de la psychologie a été le fruit d’une approche informelle.Depuis lors, la psychologie des marchés financiers est formalisée par la finance comportementale. Tout au long de son développement, ses tenants ont remis en cause l’hypothèse de rationalité des investisseurs sur des bases empiriques. Néanmoins, aucun évènement de l’ampleur de cette crise n’a autant invalidé les postulats du mainstream dominant.La théorie financière est à la croisée des chemins. L’hypothèse de rationalité des investisseurs est-elle valide ? Si oui, quelles sont les conditions de sa validité ? Si non, doit-on sortir du cadre de la finance classique et adopter celui de la finance comportementale? Ce sont autant de questions qui appellent à une refondation de la théorie financière.Le jury du Prix d’économie en la mémoire d’Alfred Nobel ne s’est d’ailleurs pas trompé en décernant le prix 2013 aux deux écoles. Cependant, les académiciens ne semblent pas trancher entre elles, reconnaissant ainsi leurs apports respectifs pour la théorie et la pratique financière. Cette récompense suggère néanmoins la question centrale suivante : les deux écoles sont-elles parallèles, complémentaires ou antinomiques?Le premier chapitre traite de la remise en cause des hypothèses centrales de la finance, à la base des modèles de gestion les plus courus. Le cadre de la finance classique n’a pas permis de donner une explication à la formation de la bulle immobilière pas plus qu’il n’a permis de fournir une solution unifiée à la crise. L’inadéquation des hypothèses du cadre classique avec la réalité apparaît notamment dans un contexte de forte volatilité et d’incertitude exacerbée. Cette remise en cause ouvre la voie à l’introduction de paramètres psychologiques dans la compréhension des phénomènes du marché.La finance comportementale développe la psychologie des marchés financiers. Le second chapitre aborde les concepts centraux de ce courant. L’analyse de ces concepts et du développement historique, épistémologique et paradigmatique du courant montre qu’il s’inscrit à l’opposé et, parfois, en complément du classique. Il n’en demeure pas moins que le cadre théorique de ce courant n’est pas encore achevé pas plus que la formation d’un paradigme dominant.Parmi les principaux résultats de la finance comportementale, les outils psychologiques apportent des clefs de lecture pertinentes des marchés financiers. Le troisième chapitre aborde les biais et heuristiques à la lumière de la crise. L’analyse de la crise montre que les heuristiques et les biais émotionnels ont pu conduire les investisseurs à des erreurs de jugements. L’attention et l’analyse se sont focalisées sur des croyances dans un contexte d’opacité de l’information et de l’environnement.La finance comportementale cherche à établir un cadre conceptuel plus élaboré. La théorie des « esprits animaux » a repris de la vigueur notamment chez les comportementalistes à orientation néo-keynésienne. Le retour à cette notion s’explique par l’importance prise de concepts liés comme la confiance, la corruption ou le rôle des histoires. D’ailleurs, les collusions corruptives et le fonctionnement du système ont failli saper durablement la confiance dans l’économie financière. Ce quatrième chapitre montre que la confiance et la corruption procèdent de la psychologie humaine et montrent le poids de celle-ci en situation d’incertitude et le rapport des hommes aux gains. / The crisis that started in 2007 have challenged the foundations of the financial system and the financial theory. This theory is based on assumptions of conventional finance including the "invisible hand" and the rationality assumption of investors which builds that of market efficiency.This crisis has highlighted the psychology of financial markets, aspects already addressed by J.M Keynes when he developed the concept of "animal spirits" to reflect the uncertainty of the economy. Until the early 1980s, the understanding of psychology has always been the result of an informal approach.Since, the psychology of financial markets has been formalized by behavioral finance. Throughout its development, its theoricians have questioned the rationality assumption of investors on empirical bases. However, no paramount event such this crisis has struck much the postulates of the dominant mainstream.Consequently, the financial theory is at the crossroads. Is the assumption of rationality of investors valid? If so, what are the conditions of its validity? If not, are we departing from the scope of conventional finance and adopt that of behavioral finance? These are all issues that are calling for an overhaul of the financial theory.The Jury of the prize in economics in memory of Alfred Nobel did not err in fact by awarding the 2013 prize to these two schools. However, academics do not seem to decide between them, recognizing their contributions to financial theory and practice. This award suggests the following central question: are the two schools parallel, complementary or contradictory?The first chapter deals with the questioning of the central assumptions of finance, at the base of the most popular business models. The framework of conventional finance has failed to give an explanation to the formation of the housing bubble nor has it helped to provide a unified solution to the crisis. The inadequacy of the assumptions of the classical framework with reality appears especially in a context of high volatility and heightened uncertainty. This challenge opens the way for the introduction of psychological parameters in understanding the phenomena of the market.Behavioral finance develops the psychology of financial markets. The second chapter covers the central concepts of this trend, in order to answer the central question of this thesis. The analysis of this trend and its historical epistemological and paradigmatic development shows it is opposite and sometimes in addition to the classic one. The fact remains that the theoretical framework of this trend is not yet completed nor the formation of a new dominant paradigm achieved.Among the key findings of behavioral finance, psychological tools provide relevant insights to developments in financial markets. The third chapter addresses the biases and heuristics in light of the crisis. The analysis of the crisis shows that heuristics and emotional biases may have led investors to judgment errors. The attention and analysis has focused on beliefs in an abstruse information and environmental context, allowing the development of heuristics. Consequently, the tools of behavioral finance can develop a mental map to this crisis.Behavioral finance seeks to establish a more sophisticated conceptual framework. The theory of "animal spirits" has regained momentum especially among behaviorists of neo-Keynesian orientation. The return to this concept is explained by the growing importance of certain concepts such as confidence, corruption and the role of stories in the context of this crisis. Moreover, collusion and corrupt system operation almost permanently undermine confidence in the financial economy. This fourth chapter shows that trust and corruption stem from human psychology and show the weight of the latter in situations of uncertainty and the relationship between men and earnings.
163

L'efficacité énergétique dans les bâtiments existants : déficit d'investissement, incitations et accompagnement. / Energy efficiency in existing buildings : investment gap, incentives and supporting measures

Varenio, Céline 20 December 2012 (has links)
Cette thèse a pour objectif d'évaluer l'efficacité des dispositifs publics qui visent à inciter les agents à rénover leur logement afin d'en réduire la consommation énergétique. Il s'agit de combiner les deux dimensions clés de l'évaluation ex-post de l'intervention : la dimension récapitulative qui revient à déterminer l'efficacité des mesures mises en œuvre et la dimension formative qui vise à comprendre les résultats obtenus et à identifier les voies d'amélioration. Cela nécessite dans un premier temps de réaliser une analyse détaillée des facteurs qui sont à l'origine du faible niveau d'investissements, qualifié de déficit d'efficacité énergétique (« energy efficiency gap »). Ce déficit est dû à la présence de défaillances de marchés, aux conséquences de la rationalité limitée des ménages, ainsi qu'aux difficultés de coordination entre agents en particulier dans le cadre de la copropriété. Dans un deuxième temps il convient d'analyser le déficit d'efficacité énergétique en comparant les prescriptions qui peuvent être issues des calculs utilisés en économie publique concernant les investissements à réaliser, avec les données issues des études de terrain sur les investissements effectifs. Cette analyse permet de bien identifier les critères de décisions des ménages et ainsi de comprendre comment les barrières à l'efficacité énergétique se manifestent. L'identification des différentes barrières permet alors, dans un troisième temps, de voir si les dispositifs d'incitations aujourd'hui en application en France permettent de lever tous les obstacles aux investissements d'amélioration énergétique. Il apparaît que la multitude de dispositifs mis en œuvre ne peut suffire à réduire fortement le déficit d'efficacité énergétique. D'une part, certaines barrières ne sont pas levées car aucun outil approprié n'existe. D'autre part, certains facteurs de blocages, ne sont que partiellement traités car l'utilisation pratique des outils diffèrent de leur conception théorique. Finalement, l'analyse des programmes de réhabilitation thermique des logements qui ont été engagés sur le territoire grenoblois permet de déterminer l'efficacité des dispositifs additionnels c'est à dire d'évaluer dans quelle mesure ces interventions «renforcées» permettent de lever les barrières qui n'ont pu l'être avec les dispositifs nationaux. La mise en perspective de ces quatre analyses successives – des causes du déficit ; de sa manifestation ; des instruments nationaux ; des programmes mis en œuvre à l'échelle locale – aboutit à la conclusion d'un nécessaire renforcement des mesures non financières pour l'accompagnement des agents afin d'amorcer la dynamique d'investissement et ainsi créer les conditions de l'efficacité des instruments économiques plus généraux. / This PhD dissertation focuses on energy efficiency policies in housing. It aims at evaluating the effectiveness of public incentives designed to increase household's investment in energy efficiency of their dwelling. To reach this objective this research combines the two key dimensions of ex-post evaluation, i.e. summary and formative dimensions. The first one aims at knowing the effectiveness of public policies whereas the other one targets to understand what the public policies' consequences are and to identify ways for improvement. To reach this purpose, the research follows four steps. Firstly, it requires a detailed analysis to understand the origins of the energy efficiency gap. This gap can be explained by markets failures, consequences of bounded rationality and coordination problem between stakeholders, especially in multi-family dwellings. Secondly, the argument progresses by drawing a parallel between results from normative analysis and from observations of actual level of investments in thermal retrofit actions. It aims at identifying investment households' criteria and then at understanding how barriers to energy efficiency raise. Thirdly, thanks to the inventory of these various energy efficiency barriers it becomes possible to examine if the incentives currently implemented in France can remove them all. It appears that the national policy does not significantly reduce the energy efficiency gap. On the one hand, some barriers remain because no tool has been proposed to overcome them. On the other hand, some barriers are only partially eliminated because the practical use of tools differs from their theoretical design. Finally, using the analysis of retrofitting programs implemented on the Grenoble area this research assesses the effectiveness of additional incentives. The objective is to know to what extent these “reinforced” policies remove barriers still existing after national tools implementation. From these four successive analyses – causes, appearance of the energy efficiency gap, national tools, programs implemented at the local level – we conclude to a necessary strengthening of non-financial measures which support agents to initiate an investment dynamic and in the meanwhile to an increase of the reliability of economic tools, such as taxes or subventions
164

Strategické řízení a možnosti jeho uplatnění ve vybraném zemědělském podniku / The strategic management and the possibilities of its enforcement in a particular agronomical company

TROUBIL, Martin January 2008 (has links)
The theoretical part focuses on the description of the development and the importance of the strategic management. The pracitcal part focuses on the analyses of the particular agricultural company called AGRO Vodňany a.s., using the methods of the strategic management. Consequently I suppose the evaluation of the possible strategies for this particular company. The last part of my dissertation focuses on the possibilities of the imrovement of the economical state of the company and as a solution I suppose the reconstruction and renovation of the pig breeding barn.
165

Os (des)encontros da fe : analise interdiscursiva de dois movimentos da Igreja Catolica / The disagreements of the faith : analysis interdiscursive of two religious movements of the Roman Catholic Church

Silva, Edvania Gomes de 18 December 2006 (has links)
Orientador: Sirio Possenti / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem / Made available in DSpace on 2018-08-08T06:23:18Z (GMT). No. of bitstreams: 1 Silva_EdvaniaGomesde_D.pdf: 3386013 bytes, checksum: d0f7b946a79f58b15f845eb23f442032 (MD5) Previous issue date: 2006 / Resumo: Este trabalho tem como principal objetivo analisar a relação interdiscursiva que constitui e atravessa dois movimentos religiosos da Igreja Católica: Teologia da Libertação e Renovação Carismática Católica. Para tanto, apresenta-se um estudo da semântica global desses dois posicionamentos. Com base na relação entre os diferentes planos do discurso (práticas, ethos, cenografia, dêixis, intertextualidade e polêmica), procura-se verificar como se constitui o espaço de trocas (interdiscurso) que antecede a gênese dos discursos da TL e da RCC. Dessa forma, o estudo da semântica global, feito com base na análise de diferentes pistas textuais, é visto como um indício que ajuda a compreender o funcionamento do interdiscurso. O eixo central das discussões desta pesquisa se situa na noção de semântica global, proposta por Maingueneau (1984), segundo a qual todos os planos do discurso estão integrados e contribuem para a constituição de um corpo discursivo. O corpus da pesquisa é formado por diferentes gêneros (artigos de jornais e revistas, livros, documentos, panfletos publicitários, letras de música, etc.) que constituem a prática interdiscursiva dos dois posicionamentos estudados. A metodologia de pesquisa utilizada está centrada no dispositivo teórico-analítico da Análise de Discurso. Os resultados das análises revelam que os dois posicionamentos discursivos analisados (Teologia da Libertação e Renovação Carismática Católica), apesar de partilharem de um mesmo espaço discursivo (ou exatamente por isso), apresentam semânticas globais que se recusam mutuamente / Abstract: The main objective of this work is to analyze the interdiscursive relation that constitutes and traverses two religious movements of the Roman Catholic Church: Theology of Liberation (TL) and Catholic Charismatic Renovation (CCR). Thus, it presents a study of the global semantics of these two positions. Based on the relation between different planes of discourse (practices, ethos, scenography, deixis, intertextuality and polemic), it tries to verify how the space of exchanges (interdiscourse) that precedes the genesis of the discourses of TL and CCR is constituted. In this way, the global semantic study based on the analysis of different textual traces is considered as an index that helps you to understand the operation of the discourse. The central axis of the discussions in this research is situated in the notion of global semantics, proposed by Maingueneau (1984), and according to it all discourse planes are integrated and they contribute for the constitution of a discursive body. The corpus is constituted by different genders (newspaper and magazine articles, books, documents, pamphlets, lyrics, etc.) that integrate the interdiscursive practice of the two studied positions. The research methodology is founded on the theoreticalanalytical framework of Discourse Analysis. The results reveal that, despite sharing the same discursive space (or exactly for this reason), the two discursive positions analyzed (Theology of Liberation and Catholic Charismatic Renovation), have global semantics which refuse one another / Doutorado / Doutor em Linguística
166

Geografia política e geopolítica no Brasil (1982-2012) / Political Geography and Geopolitics in Brazil (1982-2012)

Eduardo Karol 31 January 2014 (has links)
Esta tese discute a Geografia Política e Geopolítica produzida por geógrafos no período de 1982-2012, procura identificar quais os temas mais tratados, os lugares da produção e a existência de especialistas com ligação na formulação de políticas territoriais do Estado brasileiro. Neste sentido, questiona a renovação da Geografia no Brasil, mostra que a negligencia dos geógrafos com a análise do Estado não passou ao largo das instituições de ensino e pesquisa. Dentre os resultados alcançados, expõe a concentração da produção em poucos geógrafos, fato marcante em todo o século XX, a localização em grandes universidades dos centros urbanos e a ligação dos geógrafos como formuladores de políticas estatais de organização territorial. Conclui-se que, no período analisado, a obra de Bertha K. Becker é preponderante na Geografia Política e Geopolítica e que a renovação que pretendia olvidar a ligação dos geógrafos com o Estado não se efetivou, ao contrário viu crescer o número de trabalhos sobre políticas territoriais para o Estado. / This thesis discusses Political Geography and Geopolitics produced by geographers between 1982 and 2012, looking to identify which topics were the most discussed, the places where they were produced and the existence of specialists linked to the formulation of territorial policies of the Brazilian State. Thus, this thesis debates a new moment in Brazilian Geography, showing that the negligence of the geographers towards an analysis of the State did not go off the education and research institutions. Among the results achieved, this thesis also exposes the concentration of production in the hands of few geographers, an observed situation throughout the whole 20th century, the location of the production based on large universities in the biggest urban centers of the country, and the bond of geographers with State policies of territorial organization. It concludes that, during the period observed, the works of Bertha K. Becker are widely spread in the Political Geography and Geopolitc, and that the renew, which intended to make geographers not to produce studies about the State has failed, an in fact, the number of studies about territorial policies of the State has grown.
167

Demolish or Refurbish an Existing Building? : A bachelor thesis on the climate impact of different methods of renewing a building

Lennermark, Desirée, Bjellerup, Victoria, Bäckström, Lisa, Wedman, Lisen January 2020 (has links)
The purpose of this bachelor thesis is to evaluate different alternatives of renewal regarding an already existing building. The case study building is located in the Ulleråker area in Uppsala, Sweden and is an old mental hospital building from the 1950’s which Uppsala Municipality wishes to restore as part of a bigger investment in the neighborhood. The different alternatives that will be investigated are refurbishment, with different insulation thickness, and a complete demolition and reconstruction of a new building with either wood or concrete. Carbon dioxide emissions connected to buildings will be calculated and analyzed as two elements, one being embodied carbon dioxide, and one being energy usage. Other aspects of interest, the economy and cultural values of the area, will be discussed. To estimate the amount of CO2 emissions, several life cycle assessments will be executed through the software One Click LCA (2015). Calculations will be done by hand in order to estimate the energy usage. Information and data are partly obtained from Uppsala Municipality, partly from literature and available resources. The results show that each option has a different advantage, the refurbishment resulting in considerably lower embodied carbon (114 kg CO2e/m2) but higher energy usage (95 kWh/m2 per year) as compared to the new concrete construction with larger amount of embodied carbon (279 kg CO2e/m2) but lower energy usage (44 kWh/m2 per year). This leads to a conclusion showing that a deep refurbishment is the best option regarding both embodied carbon and energy usage.
168

Obnova a rekonstrukce malé vodní nádrže / Renovation and reconstruction of small water reservoir

Pavlík, Tomáš January 2018 (has links)
This diploma thesis deals with analysis of small water reservoirs and their water management. The work is divided into two parts. The first part contains research and the second one is dedicated to the project of small water reservoir. The research describes the basic division of small water reservoir and their construction and technical equipage. The knowledge that has been found is applied in the project. The project describes the renovation of small water reservoir Kančí obora and pool, in k.ú Nové Bránice and Moravský Krumlov.
169

Renovación del pabellón de cuidados intensivos del hospital Luis N. Sáenz de la PNP – Jesús María / Renovation of the Intensive Care Pavilion of Luis N. Sáenz Hospital - Jesús María

Angulo Portocarrero, Kyara Celeste 13 March 2019 (has links)
Esta investigación tiene como propósito principal desarrollar un proyecto de diseño interior para la renovación del pabellón de la Unidad de Cuidados Intensivos (UCI) del Hospital de la Policía Nacional del Perú Luis Nicasio Sáenz (Jesús María), de manera que se mejore su funcionalidad y confort. Como objetivos específicos, se plantearon proponer replanteamientos de distribución según las zonas negra, gris y blanca; proponer un diseño de iluminación que permita a los usuarios cumplir con las funciones habituales del área; y plantear un diseño que otorgue identidad, de manera que este pueda ser replicado en cada área del hospital. En esa línea, se desarrolla la problemática actual del entorno hospitalario, se conceptualiza qué es una UCI, sus características y tipos; asimismo, se expone cómo la arquitectura se articula con la humanización. En cuanto a la estrategia de diseño, esta incluye el diagnóstico, la intervención y aspectos específicos, como en el uso de colores, materiales e iluminación. Esta información se presenta mediante diversas figuras, que detallan el programa arquitectónico, el organigrama y la zonificación de espacios. Los desperfectos encontrados en el nosocomio sirven de partida para realizar la nueva propuesta de diseño. Las ideas se plantean de acuerdo con guías normativas para la implementación de una unidad tan crítica, de manera que el resultado sea un espacio que resulte funcional para el equipo del personal médico, así como confortable para los pacientes. / The main purpose of this research is to develop a project of interior design for the renovation in the pavilion of intensive care unit (ICU) of the National Police Hospital of Perú Luis Nicasio Sáenz (Jesús María), to improve its functionality and comfort. As specifics objectives, it is proposed a new distribution according to black, gray and white areas; also it is proposed a lighting design that allows users to acomplish with the usual functions of the area; and it is propose a design that give an identity, so that could be replied in different areas of the hospital. Therefore, the current problems of the hospitals are developed, the concept of a intensive care unit (ICU) is conceptualized, also its characteristics and types; additionally, it is exposed how the architecture articulates with humanization. For the design strategy, diagnostics, interventions and specific aspects, such as the use of colors, materials and lighting, are included. This information is presented in figures, which detail the architectural program, the organization chart and the zoning of the spaces. The problems found in the hospital serves as a starting point to carry out the new design proposal. The ideas are presented in accordance with normative guidelines for the implementation of a critical unit, so that result while be a space that is functional for the team of medical personnel, as well as comfortable for patients. / Tesis
170

Renovering av Gamla Årstabron med injekteringsbetong / Renovation of the Old Årsta bridge using pre-placed aggregate concrete

Stolt, Jens January 2015 (has links)
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.

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