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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.
61

Miljöpåverkansanalys av bärande träbyggnadssystem / Environmental impact analysis of load bearing wooden building systems

Askemar, Hanna January 2019 (has links)
Klimatpåverkan från bygg- och fastighetssektorn står för ungefär en femtedel av det totala utsläppet av växthusgaser i Sverige. I och med att utsläppen från energianvändningen i användningsskedet av en byggnad minskar behöver fokus flyttas till bland annat byggskedet. I byggskedet står den bärande stommen för en betydande del av en byggnads klimat- och miljöpåverkan. Inom Lokalförvaltningen i Göteborgs innovationsprojekt Hoppet syftar examensarbetet till att utreda olika träkonstruktioners klimatpåverkan och miljöprestanda. De stomkonstruktioner som kommer att jämföras är bärande ytterväggar med bärande element i LVL, konstruktionsvirke, lättviktsregel och KL-trä. För bjälklag kommer konstruktioner med bärande element av LVL och lättviktsbalk att analyseras. Metoden som används för att utreda träkonstruktionernas miljöprestanda är livscykelanalys. Livscykelanalysen genomförs på tvärsnitt av de olika träkonstruktionerna som är framtagna i dialog med leverantörer av träteknikerna, för att uppfylla den funktionella enheten i analysen. Resultatet av livscykelanalysen indikerar att för bärande ytterväggar har tvärsnittet med KL-trä lägst miljöpåverkan i flest kategorier. Tvärsnittet med KL-trä har även lägst klimatpåverkan. För bjälklag har tvärsnittet med lättviktsbalk lägst påverkan i flest miljöpåverkanskategorier. Resultatet tyder även på att det framförallt är isolering och gips som står för majoriteten av tvärsnittens miljöpåverkan i samtliga miljöpåverkanskategorier. Efter en känslighetsanalys av tvärsnitten blir det även tydligt att om miljöpåverkan från isolering minskas, förändras fördelningen av resultatet i de olika miljöpåverkanskategorierna. Det vill säga andra träbyggnadstekniker får lägst respektive högst påverkan än vid tidigare jämförelse. Slutsatsen i arbetet blev i enlighet med resultatet att tvärsnittet med KL-trä har lägst klimatpåverkan och även lägst påverkan i flest miljöpåverkanskategorier för bärande ytterväggar. För bjälklag är klimatpåverkan från LVL och lättviktsbalk mycket lika, lättviktsbalken har däremot lägst påverkan i flest miljöpåverkanskategorier. För att minska miljöpåverkan från ett tvärsnitt är det däremot framförallt isolering och gips som bör uppmärksammas. De livscykelstadie som bidrar till störst miljöpåverkan är produktionen av material, därefter bidrar användningsskedet i form av utbyte av material till stor miljöpåverkan. / In Sweden, the building sector is responsible for approximately one-fifth of the emissions contributing to climate change. Emissions from the use-stage have decreased the last 30 years and therefore the importance of reducing the emissions from the product and construction stage increases. The structural elements in a building contribute with a significant part of the emissions from the product and construction stage.   Within the local administration of the City of Gothenburg’s innovation project “Hoppet” this thesis aims to investigate different wooden constructions impact on climate change and six other environmental impact categories. The wooden constructions that are included in the thesis are load-bearing walls with laminated veneer lumber (LVL), building timber, lightweight beam and cross-laminated wood (CLT). The investigated wooden constructions that are included for the floor construction are LVL and lightweight beam.   The method that is used to calculate climate- and environmental impacts is life cycle assessment(LCA). The LCA is performed on cross-sections of the different wooden constructions. The cross-sections have complied with the suppliers of each wood construction supplier to fit the functional unit.   The result of the LCA indicates that, for the load-bearing wall, the cross-section with CLT has the lowest environmental impact in most impact categories. The cross-section with CLT also has the lowest impact on climate change. For the floor construction, the cross-section with a lightweight beam has the lowest impact in most impact categories. Although the impact on climate change is very similar between the two cross-sections.   The result also indicates that it is mainly the insulation and gypsum that contributes with the majority of the environmental impact in all categories. After a sensitivity analysis, it is clear that the environmental impacts from the cross-sections vary depending on the environmental impact from insulation.
62

Caractérisation microstructurale et électrique de couches céramiques obtenues par le dépôt électrophorétique (EPD) : Application à la zircone cubique

Simone, Antonia 23 January 2004 (has links) (PDF)
Le dépôt par électrophorèse, technique éclectique et prometteuse, est bien connue pour permettre la production de films déposés de haute qualité et d'épaisseur contrôlée. Au vu de ces possibilités, la technique EPD a été appliquée avec succès lors de ce présent travail de thèse de doctorat pour produire des couches à base de zircone yttriée orientées vers des applications comme électrolyte solide dans les piles à combustibles. Nous avons testé deux techniques simples, facilement transférables à la production industrielle : La sérigraphie et le dépôt par électrophorèse. Les caractéristiques microstructurales de ces couches se reflètent sur leur comportement électrique. Notamment, les couches électrophorétiques possèdent des valeurs de conductivité plus élevées et proches des valeurs théoriques. Ces valeurs couplées au fait de pouvoir développer des couches d'épaisseur faible contrôlée (de l'ordre de la dizaine de µm), démontrent combien le dépôt par électrophorèse est une réponse valide aux demandes d'amélioration des caractéristiques des couches d'électrolytique.
63

Europos paveldo dienų istorija ir raida Lietuvoje / History and development of the european heritage days in lithuania

Okaitė, Indra 24 November 2010 (has links)
Idėja pradėti rengti Europos paveldo dienas gimė Prancūzijoje 1984 metais. Jos iniciatorius – Prancūzijos kultūros ministras Jack Lang. Per keletą metų šis renginys išplito po daugelį Europos šalių ir pasidarė toks populiarus, jog nuo 1991 metų Europos Tarybai inicijavus ir parėmus Europos Sąjungai visoje Europoje imta rengti Europos paveldo dienos. EPD renginiai skirti visuomenei, siekiant ją supažindinti su kultūros paveldu, parodyti tai, kas visuomenei neprieinama arba aktualizuoti vienokią ar kitokią kultūros paveldo sritį. Labiausiai, tikimąsi šia programa sudominti moksleivius ir paskatintii juos domėtis savo šalies kultūra, istorija. Ta proga Europos Taryba bendradarbiaudama su Katalonijos (Ispanija) kultūros paveldo specialistais nuo 1995 – ųjų rengia vaikų tarptautinį fotografijos konkursą “Kultūros paveldas fotografijoje”. Konkurse dalyvauti taip pat gali visos jaunimo grupės pateikusios europinį projektą, atitinkantį keliamus reikalavimus. Lietuva šiame tarptautiniame fotografijos konkurse dalyvauja nuo 1999 – ųjų metų jau aštuonerius metus. Išrinkti geriausieji darbai siunčiami į tarptautinį turą Ispanijoje, Barselonoje. Visos nugalėjusios fotografijos publikuojamos Europos Tarybos leidžiamame kataloge, kuris yra platinamas 50 valstybių. EPD atidarymo ceremonija sukviečia daug radijo ir televizijos kompanijų iš įvairių Europos šalių – geresnės reklamos turizmui negalima tikėtis. Tai yra įspūdingas lankytojų ir dalyvių skaičiumi renginys. Besidomintys kultūros... [toliau žr. visą tekstą] / The French Minister of Culture suggested extending to a European level the “Monuments’ Open Doors” initiative launched in France in 1984. Several European countries, such as The Netherlands, Luxemburg, Malta, Belgium, the United Kingdom (Scotland) and Sweden soon set up similar events. In 1991, the Council of Europe officially launched the European Heritage Days (EHDs) with the support of the European Commission. In 1999, this initiative became a joint action of the Council of Europe and the European Commission. Throughout Europe, during the weekends of September, the European Heritage Days open the doors of numerous monuments and sites, many of them usually closed to the public, allowing Europe’s citizens to enjoy and learn about their shared cultural heritage and encouraging them to become actively involved in the safeguard and enhancement of this heritage for present and future generations. Today, the European Heritage Days can be considered an essential instrument for fostering a tangible experience of European culture and history in addition to raising the awareness of the public about the multiple values of our common heritage and the continuous need for its protection. All 49 States parties to the European Cultural Convention actively take part in the initiative and the number of annual visitors is now estimated to be around 20 million at more than 30,000 participating monuments and sites. The EHDs have succeeded in stimulating civil society’s participation, the... [to full text]
64

Polimorfismos dos genes MUC1 e Osteopontina em novilhas da raça Nelore (Bos taurus indicus) / Polymorphisms in MUC1 and osteopontin genes in Nelore heifers

Fabio Ricardo Pablos de Souza 03 May 2007 (has links)
A MUC1 (MUC1) e a osteopontina (SPP1) são glicoproteínas expressas na superfície luminal uterina com funções na proteção e adesão celular. A MUC1 possui função antiadesiva, enquanto a osteopontina desempenha função adesiva. A expressão de ambas é regulada pelo hormônio esteróide progesterona. Durante a fase receptiva do útero, a MUC1 é inibida por este hormônio, enquanto a osteopontina é estimulada. O objetivo deste trabalho é caracterizar o polimorfismo genético destas moléculas e analisar a associação entre o polimorfismo, o diagnóstico de gestação e as diferenças esperadas na progênie (DEP) de várias características em novilhas da raça Nelore (Bos taurus indicus). A amostra foi constituída por 309 novilhas procedentes de duas fazendas participantes do Programa de Melhoramento Genético da Raça Nelore (PMGRN). A amostra da primeira fazenda incluiu 56 novilhas prenhas e foi utilizada para caracterização do polimorfismo e da estrutura do número variável de repetições em tandem (VNTR) MUC1 na raça Nelore. A segunda amostra foi constituída por 76 novilhas com resultado positivo de gestação e 156 com resultado negativo de gestação e foi utilizada para caracterização do polimorfismo dos genes MUC1 e SPP1 na raça Nelore, assim como para análise da associação entre os polimorfismos e os fenótipos. O gene MUC1 apresentou 5 alelos constituídos por um VNTR formado por uma seqüência de 60 nucleotídeos. A seqüência da repetição consensus foi idêntica às seqüências descritas em caprinos e em Bos taurus taurus. Descrevemos a seqüência de uma terceira repetição consensu na raça Nelore. O alelo 1 apresentou 10 repetições, o alelo 2 apresentou 12 repetições, o alelo 3 apresentou 15 repetições, o alelo 4 foi formado por 18 repetições, e o alelo 5 apresentou 24 repetições. O alelo com menor número de repetições apresentou a maior freqüência, sendo 0,70 na amostra do 1º grupo e 0,80 na amostra do 2º grupo. Os alelos 2, e 3 tiveram a segunda e terceira maior freqüência, sendo seguidos pelos alelos 4 e 5. A análise estatística não evidenciou associação entre o polimorfismo do gene MUC1 e o diagnóstico de gestação e entre o polimorfismo e os valores das diferenças esperadas na progênie das características consideradas economicamente importantes. Na amostra referente às novilhas da segunda fazenda, não identificamos o polimorfismo de nucleotídeo simples no íntron 4 (T/C) do gene SPP1 da osteopontina, como descrito na raça Holandesa. Sugerimos que a ausência deste polimorfismo possa constituir uma característica específica em Bos taurus indicus. Porém, dada a associação já descrita entre polimorfismo do gene SPP1 e características de crescimento, não descartamos a hipótese de que, assim como o MUC1, tenha ocorrido uma seleção indireta devido aos critérios aplicados pelo Programa de Melhoramento Genético da Raça Nelore. / MUC1 (MUC1) and osteopontin (SPP1) are glycoproteins expressed in the uterine luminal surface with predict functions in protection and cell adhesion. MUC1 has anti-adhesive role and osteopontin has adhesive role. The expression of both molecules is regulated by the steroid hormone, progesterone. During the receptive period for embryo implantation in the uterus, MUC1 is inhibited by progesterone and the osteopontin is stimulated. The objective of this work is to characterize the genetic polymorphism of these molecules, and to characterize associations between the polymorphisms, gestation rate and the expected progeny difference (EPD) in the Nelore breed (Bos taurus indicus). The study group comprised 309 heifers derived from two participating farms of the Nelore Cattle Breeding Program (PMGRN). The first farm provided 56 fertile female for the study for the characterization of the MUC1 polymorphism and the variable number of tandem repeats (VNTR) genomic structure in the Nelore breed. The second farm contributed 76 heifers with confirmed gestation and 156 no-pregnant female that were used to characterize both gene polymorphisms and to analyze the association between the MUC1 and SPP1 polymorphisms and the phenotypes. The MUC1 gene presented five alleles caused by length differences generated by a VNTR of 60 nucleotides. The consensus repeat sequence was identical to the caprine and Bos taurus taurus sequence. In this study we described the sequence of the third consensus repeat in the Nelore breed. Allele 1 presented with 10 repeats, allele 2 presented with 12 repeats, allele 3 presented with 15 repeats, allele 4 had 18 repeats and allele 5 had 24 repeats. Allele 1 had the smallest size and was the most frequent (0.70) in the group 1 and 0.80 in the group 2. Alleles 2 and 3 were the next most frequent followed by alleles 4 and 5. The ?2 test showed that the polymorphism was not significantly associated with the diagnostic of gestation and the EPD values. In this Nelore study group it was not possible to identify the single nucleotide polymorphism (T/C) of the SPP1 gene previously described in Holstein breed. The absence of this polymorphism could be specific to the Nelore cattle. However, considering the correlation between the SPP1 polymorphism and growth parameters, an indirect selection could happen due to the established criteria within the Nelore Cattle Breeding Program.
65

Synergistic use of promoter prediction algorithms: A choice for small training dataset?

Oppon, Ekow CruickShank January 2000 (has links)
Philosophiae Doctor - PhD / This chapter outlines basic gene structure and how gene structure is related to promoter structure in both prokaryotes and eukaryotes and their transcription machinery. An in-depth discussion is given on variations types of the promoters among both prokaryotes and eukaryotes and as well as among three prokaryotic organisms namely, E.coli, B.subtilis and Mycobacteria with emphasis on Mituberculosis. The simplest definition that can be given for a promoter is: It is a segment of Deoxyribonucleic Acid (DNA) sequence located upstream of the 5' end of the gene where the RNA Polymerase enzyme binds prior to transcription (synthesis of RNA chain representative of one strand of the duplex DNA). However, promoters are more complex than defined above. For example, not all sequences upstream of genes can function as promoters even though they may have features similar to some known promoters (from section 1.2). Promoters are therefore specific sections of DNA sequences that are also recognized by specific proteins and therefore differ from other sections of DNA sequences that are transcribed or translated. The information for directing RNA polymerase to the promoter has to be in section of DNA sequence defining the promoter region. Transcription in prokaryotes is initiated when the enzyme RNA polymerase forms a complex with sigma factors at the promoter site. Before transcription, RNA polymerase must form a tight complex with the sigma/transcription factor(s) (figure 1.1). The 'tight complex' is then converted into an 'open complex' by melting of a short region of DNA within the sequence involved in the complex formation. The final step in transcription initiation involves joining of first two nucleotides in a phosphodiester linkage (nascent RNA) followed by the release of sigma/transcription factors. RNA polymerase then continues with the transcription by making a transition from initiation to elongation of the nascent transcript.
66

Concrete Guidance? : An empirical study examining attitudes in regard to The Act of Climate declarations and its influence on the construction industry.

Hildebrandsson, Sammy, Anna, Olsson January 2022 (has links)
The construction industry is one of Sweden's largest industry emitters, an industry operating in the centre of cities worldwide, day and night. In order to achieve a more sustainable future and reduce greenhouse gas emissions, the construction industry must be less pollutive. On 1 of January 2022, the Swedish government implemented new regulation, The Act of Climate Declarations, within the construction industry, to enhance the knowledge of the climate impact of new buildings. The purpose of this study is to examine the implementation process of said regulation, its implications on concerned industry actors, and to investigate whether current restrictions would benefit from more strict policies or not. In this study, Institutional theory has been applied to analyse conducted empirical data to examine how the regulation has influenced different actors behaviours and practises. The result shows that the regulation has been widely accepted within the industry. Furthermore, this study shows that barriers are mainly found regarding the narrow scope the regulations require. Opportunities in regards are that actors are hopeful that the regulations could be a first step toward a more sustainable industry at large. These findings have added evidence that adds to current literature on future sustainability investments, such as limit-values and new proposals communicated by the Swedish Government while this thesis was written.
67

Hur återbruk kan främjas inom Skolfastigheter AB / Reuse of construction materials within Skolfastigheter AB

Sadjak, Oliver, Johansson, Pontus January 2023 (has links)
The United Nations aims to achieve net-zero carbon emissions by 2050, while Sweden has seta target to reach net-zero emissions in the construction industry by 2045. In 2020, constructionaccounted for approximately 21% of Sweden's domestic CO2 emissions. To meet these goals, a roadmap has been developed, targeting net-zero emissions by 2045. Skolfastigheter AB, among others, are compelled to take action to reduce greenhouse gas emissions and one wayto align with the climate objectives is to promote reuse. However, the company currently lacksan established approach for reuse. This report focuses on reducing the environmental impact of renovation projects within Skolfastigheter AB through reuse. The objective is to identify reuse prerequisites and developstrategies for promoting reuse in renovation projects. The theoretical background covers the circular economy, waste hierarchy, material reusepotential, requirements, specifications, sales, and BIM in relation to reuse. Two schools under Skolfastigheter AB:s management are observed, and interviews are conducted with nine actors in the construction industry. The results reveal a similar material structure in the observed schools. Furthermore, it reveals challenges such a lack of documentation of materials, reoccurring vandalism and that reuse has been absent withing the management. The interviews provide nine categories to promote reuse in renovation projects: a systematic working model, inventory, quality, BIM tools, competence, design choices, hazardous substances, collaboration, and EPDs. Conclusions highlight the prioritization of installations and porcelain for reuse, emphasizing the importance of the working model, inventory, and quality as key factors for promoting reuse.
68

En jämförelse av väggstommar:limträbaserat pelar-balksystemoch korslaminerad träskiva : Med avseende på stabilitet, miljömässiga ochbrandtekniska aspekter

Said, Haydar, Al Smady, Omran January 2023 (has links)
Wood is a sustainable material that reduces the climate impact that comes from the construction sector. In addition, Wood is economical and offers many advantages such as the low weight, that it is a renewable material and the flexibility. However, in order for Wood to be durable and have a smaller climate impact, the right construction method should be used for each type of building, otherwise it can lead to collapse.In this thesis, the most durable and stable construction method was investigated between column-beam systems in glulam and CLT board, for a machine hall building made of wood, based on factors such as environmental impact, fire resistance and stability. The investigation used FEM-Design software to analyze the course of the fire, which facilitated a more comprehensive analysis and reduced the risk of human error. FEM Design simplified the use of more complex methods that required greater knowledge and longer time to implement. In contrast, hand calculations were used for the stability comparison and data were collected for the environmental impact from EPDS. The study showed that glulam structures have higher stability capabilities with a superiority of 2.1% in compressive strength, 9,1% in flexural strength, 3,5 % shorter in breaking length and 86% lower in slenderness ratio indicating the probability of deformation under load compared to crosslaminated timber (CLT) making it a preferred material for larger constructions. Glulam also generates around 5% less CO2 emissions per cubic meter compared to CLT. In terms of fire safety, CLT performed better under a 60-minute fire exposure and required less Class F gypsum board as fire protection. Choosing a construction method is a multidimensional assessment that weighs factors such as construction site, the nature of the construction project and personal preferences, despite specific research findings.
69

En studie om konstruktörer kan minska klimatpåverkan av koldioxid från betong via kravspecifikation / A study about if construction designers can reduce the climate impact of carbon dioxide from concrete through specifications

Staffansson, Frida January 2019 (has links)
Syfte: Byggindustrin kommer framförallt att påverkas av hållbarhetsutvecklingens framfart. FN har satt hållbarhetsmål presenterade i Agenda 2030 och för att möta dessa mål måste hållbarhet stå i fokus för både yrkesverksamma och intressenter. Betong är ett material som består av ballast, vatten och cement som hårdnar över tiden och används världen över inom byggindustrin. År 2014 uppskattades betongproduktionen stå för hela fem procent av alla antropogena koldioxidutsläpp. Syftet med studien är att undersöka miljöpåverkan från olika betongkvaliteter mätt i koldioxidekvivalenter och använda resultatet för att påvisa om konstruktörer kan göra någon skillnad via sina kravspecifikationer på betong. Metod: En litteraturstudie genomfördes inledningsvis för att säkerställa studiens relevans samt skapa kunskap kring området. LCA och dokumentanalys av EPD möjliggjorde jämförelse av klimatpåverkan och data kunde sammanställas. Resultat: Sammanställd och jämförd data från LCA och dokumentanalys tyder på att konstruktörer kan minska klimatpåverkan genom att föreskriva högre vct och lägre exponeringsklass. Detta möjliggör att en större andel cement kan bytas ut mot tillsatsmaterial. Litteraturstudie tyder på att konstruktörens arbete för att minska klimatpåverkan från betong kan direkt kopplas till mål 13 i Agenda 2030. Mål 13 verkar bland annat för att Sverige inte skall ha några nettoutsläpp av växthusgaser 2045. Konsekvenser: Om konstruktörer i den mån det är möjligt föreskriver högre vct och lägre exponeringsklasser tyder studien på att de kan minska klimatpåverkan från betong. Att föreskriva högre vct och lägre exponeringsklasser är dock inte alltid möjligt med hänsyn till hållfasthet och omgivning. Studien bidrar till att skapa förståelse för hur stora skillnader gällande klimatpåverkan som kan uppstå beroende på betongkvalitet. Begränsningar: Betong erhåller många egenskaper och en uppsjö av parametrar som påverkar dessa egenskaper. Genom att avgränsa studien och bortse från en del parametrar finns risk för orättvisa resultat. Data som används är publicerad data samt data som betongleverantören vill tillge vilket ger ett bristande verklighetsperspektiv. Majoriteten av betongkvaliteterna som analyserades är av en klimatförbättrad betong och har därmed en lägre klimatpåverkan än vad som vanligen används på plats om inte krav finns. På grund av omgivning och andra förhållanden är det inte alltid möjligt för konstruktören att föreskriva högre vct och lägre exponeringsklass. Studiens fokus ligger på klimatpåverkan vilket begränsar möjligheten att koppla resultatet till flera miljömål. / Purpose: The construction industry will be fundamentally impacted by sustainable development progression. The United Nations have set goals outlined in the 2030 Agenda for sustainable development. To meet this desired progression, these goals must stand in focus for construction professionals and industry stakeholders. Concrete is a composite material made from aggregates, fluids and cement which hardens over time and is widely used in the construction industry. In 2014 it was estimated to account for more than five percent of all anthropogenic carbon dioxide emissions. The purpose of this study is to investigate the climate impact of various concrete mixtures measured as carbon dioxide equivalents and use this to inform whether construction designers can make a difference through the specifications of concrete mixtures. Method: A literature review was conducted to ensure relevance of the study and establish a knowledge base regarding the subject. LCA and a document analysis of EPDs made it possible to compare climate impacts and data could be compiled. Findings: Data from LCA and document analysis indicates that construction designers can reduce the climate impact through their specifications by subscribing higher w/c ratios and lower exposure classes. This enable a bigger amount of the cement to be traded by additives. A literature study indicates that reducing the climate impact of concrete can directly be related to goal 13 in Agenda 2030. In Sweden, goal 13 is to reach no net emissions of greenhouse gases by 2045. Implications: If construction designers specify higher w/c ratio and lower exposure classes, they can reduce the climate impact from concrete. To specify higher w/c ratio and lower exposure class is not always possible depending on the structural requirements. The study adds to an understanding of the climate impact depending on concrete mixtures. Limitations: Concrete obtains many characteristics which is affected by multiple parameters. Limiting the study data and ignoring some parameters increases the risk of deceptive results. Publicly available concrete certifications and data from concrete professionals is combined in this study. Most of the concrete mixtures selected for analysis are climate friendly types and therefore the results would differ if regular concrete was used. Because of structural requirements and other conditions, it is not always possible for the construction designer to specify higher w/c ratio and lower exposure class. This study focuses on climate impacts which limits the possibility to make connections to multiple sustainable development goals.
70

Hållbart byggande för konstruktörer : Beslutunderlag för minskad miljöpåverkan i tidiga skeden / Sustainable construction for structural engineers : Decisions basis for reduced environmental impact in early stages

Barmicho, Romil, Flensburg, Olle January 2020 (has links)
Hållbarhet är något som påverkar alla. Det är en utmaning att minska överutnyttjandet av jordens resurser samtidigt som befolkningsmängden ökar. Byggsektorn har en stor påverkan på samhället och står inför flera utmaningar i sitt arbete med att minska klimat- och miljöpåverkan. Materialval är en viktig del då de största utsläppen oftast sker vid tillverkning av byggnadsmaterial.Detta arbete gjordes för att belysa hur viktig konstruktörernas del i hållbarhetsarbetet är och visa att de kan vara med och påverka beställarens beslut. Syftet med examensarbetet var att underlätta hållbarhetsarbetet i projekteringsskedet vid val av stomsystem. Konstruktörer ska kunna visa att grundläggande hänsyn tagits till minskad miljö- och klimatpåverkan. Syftet var också att utreda hur hållbarhetskonsulters analyser av konstruktörers arbete lättare kan utföras.I detta arbete utfördes semistrukturerade intervjuer tillsammans med en enkät för att utreda vilka delar som behövde utvecklas mellan projekteringsprogam och LCA-verktyg för att förenkla utförandet av en livscykelanalys (LCA). Utöver utredningen gjordes en fallstudie på ett referensobjekt i form av tre framtagna alternativ för stommar. Fallstudien utfördes genom en förenklad LCA i projekteringsprogrammet Revit. Den data som användes för de ingående materialen sammanställdes först i en lista med emissionsvärden för klimatpåverkan, ozonnedbrytning, försurning och övergödning. Dessa värden hämtades från olika miljövarudeklarationer (EPD:er) som fanns publicerade i publika databaser. Därefter formades ett ”Schedule” i Revit för att visa miljöpåverkan från de olika stomalternativen direkt i programmet. Listan utformades som en informationsguide och framtagningen av ett ”Schedule” i Revit förklaras grundligt för att konstruktörer ska kunna ta hjälp av detta vid framtida projekteringar för en minskad miljöpåverkan.Resultatet av utredningen visar att många av de utmaningar som tidigare studier har visat fortfarande är aktuella. Bland dessa är kravställandet på projekteringen en av de punkter som nämns mest. Flera förslag på hur kravställandet kan gå till nämns bl.a. genom en matris som vanligtvis används vid kravställande i projekt med BIM-samordning. Vidare ansåg intervjupersonerna att en kravställningsmall bör tas fram för att kunna användas i samtliga projekt, även om inte en LCA ska utföras.Det resultat som fallstudien visar var att stomalternativet i stål är det som påverkar miljön mest i alla kategorier som jämfördes. Träalternativet visade sig inte vara nämnvärt mycket lägre än betongalternativet ur klimatpåverkansperspektiv. Detta på grund av de avväxlingsbalkar i stål som användes för att avlasta det befintliga planet som stommen skulle byggas på. Det visas genom ett cirkeldiagram och analyseras vidare i diskussionen. / Sustainability is something that affect us all. It´s challenging to reduce the over-utilization of the earth’s resources at the same time as the population is increasing. The building sector has a big impact on the society and faces several challenges in the work to reduce climate and environmental impacts. Material choice is an important part because the largest emissions comes from the manufacturing phase.This study was made to highlight the importance of structural engineer’s part in the sustainability work and the impact on the purchaser’s decision. The purpose of this degree project was to support the sustainability work in the design stage when choosing a load bearing structure. The structural engineer could show that basic consideration was taken to reduce the environmental and climate impacts. The purpose was also to investigate how to facilitate sustainability consultants’ assessments of the work delivered by structural engineers.Semi-structured interviews were conducted together with a survey to investigate the parts in need of further development between design programs and LCA-applications in the process to execute and simplify sustainability analysis. Besides the investigation, a case study was made on a reference object. The object had three alternatives of load bearing structures. The case study was performed through a simplified LCA in Revit. The data that was used for the included materials was compiled to a schedule with emission values of climate influences, ozone decomposition, acidification and overfertilization. These emission values were retrieved from different EPD:s hat was published in open access databases. After the emissions were retrieved a schedule was made in Revit that showed the environmental impact for the different structural alternatives.The schedule was designed as a guide and the development of a schedule in Revit is explained thoroughly as guidance for structural engineers in future projects to reduce the environmental impact.The results of the investigation show that a lot of challenges that former studies have shown are still valid. Among these challenges, most of the respondents mentioned the prerequisites for projects to be one of the main points. One of the many proposals on how the setting requirements would take place was through a matrix that often is used in projects with BIM-coordination. Furthermore, the interviewers felt that the requirements for data should be developed for all projects, even though an LCA-analyze is not required.The results from the case study show that structures in steel affected the environment most in all the categories that was compared. The wood option showed that it was not that much lower from a climate impact perspective compared to the concrete option. This was because of the members in steel that was used to unload the existing floor which the structure would build on. This is shown with a pie chart and is further analyzed in the chapter of discussion.

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