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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.
21

Digitala plattformar som främjar återbruk : En studie som undersöker möjligheter att förbättra dagens digitala plattformar för återbruk i rivning- och ombyggnadsprojekt / Digital platforms to promote recycling

Lifh, Nellie, Wahlman, Cornelia January 2022 (has links)
There is a global consensus that the countries of the world must work to ensure a sustainable future for the next generations and Sweden is no exception. The construction sector is responsible for about a third of the generated waste in Sweden. To be able to impact and reduce the current global footprint, the sector needs to aim for a change. One of the ways to promote a sustainable construction sector is to increase the reuse of building materials in current projects. The companies use digital platforms to facilitate the coordination of this process to increase the effectiveness of the project. The goal of this thesis is to explore the conditions that are needed for the building sector to be able to implement reused building materials by using digital platforms. The digital platforms are used as tools to expand and promote reuse of former building materials in projects by facilitate the selling and the purchase process. This study is primarily centered upon the digital platforms CCBuild, Palats, Loopfront and BuildID. The methodology of this study is based on a literature study, interviews and a case study in which the district of Hugin is used as a reference. In this study the company Vasakronan is also introduced because of their experice with digital platforms in their projects. Vasakronan is currently working with the renovation project of the Hugin district located in the center of Uppsala. Their partner in this project is Byggstyrning and they are both to their greatest extent working to reduce waste by using reused building materials from the former parts of the building. The results of this case study indicate that there are areas that need an improvement. It also points out the need for a software program that can register data from Excel files directly into the platforms. To increase the quantity of reused material in projects where digital platforms are used, there is a need to focus on the following points: tools for inventory, increase marketing, interoperability of the digital platforms, but also implementation of standards to make it possible to connect to BIM-models. The result shows the challenges with implementation of reused building materials in projects according to the following points: the customers are the key decision makers, building materials lose their original quality, but also the lack of knowledge.
22

Hantering av materialdokumentation under projekteringsskedet

Abou Absi, Nicole, Karakurt, Reyhan January 2019 (has links)
Denna studie riktar sig på att kartlägga hur materialdokumentation upprättas för att uppfyllaBoverkets krav gällande förslag till lag. Det undersöks även vilka brister företagen upplevermed materialdokumentation och informationshantering. Vidare undersöks om BIM kan vara enlösning till kommunikationsproblem och underlätta informationshantering. I arbetet har detfokuserats på materialdokumentationen endast under projekteringen.Utredningen i studien har verkställts med kvalitativa metoder, litteraturstudie och intervjuer.Data som samlas in med hjälp av intervjuer används som primära källor kring den aktuellastudien. Respondenterna till intervjustudien är aktörer av olika slag och som anses haerfarenheter med materialdokumentation.Resultatet av studien visa att materialdokumentationen upprättas mest under produktioneneftersom företagen köper det mesta materialet under det skedet. Det som görs underprojekteringen är att företagen mest överväger och planerar hur dokumentationen ska gå till.Det som eventuellt kan dokumenteras under projekteringen är sådana material som bestäms itidiga skeden. Det som brister när företagen ska dokumentera är att materialdatabaserna ochklassifikationssystemen upplevs komplexa och överarbetade, vilket leder till att det inte läggsmycket tid på det och även att det ibland undviks att upprättas. BIM visar sig vara en lösningtill kommunikationsproblem och underlätta informationshantering, men den utnyttjas inte tillsin fulla potential eftersom det är många som inte har datorvana och kunskaper inom BIM.Vilket leder till att även BIM oftast väljs bort. / This study aims to identify how materialdocumentation is prepared to meet the requirements of the Swedish National Board of Housing, Building and Planning. It also examines which flaws the companies experience with materialdocumentation and informationmanagement. Also, further investigations on BIM are done, to see if it can be a solution to the problems. This study focuses on the materialdocumentation, but only during the project planning.The study was conducted with qualitative methods, literature studies and interviews. Datacollected using interviews are used as primary sources. The respondents to the interviews are workers of various kinds and are considered to have enough experience of materialdocumentation.The result of the study has shown that the materialdocumentation is mostly used duringproduction, because the companies buy the most material during that stage.The companies lack knowledge when it comes to documenting and using the material databases. This is because the classification systems are experienced to be complex and overworked. BIM turns out to be a solution to the problems, but it isn’t used to its full potential. This is because there are many who don’t have computer experience and knowledge within BIM.
23

An Analysis of Alternative Building Materials in the Coastal Rural Areas of Bangladesh / En analys av alternativa byggnadsmaterial i de kustliga landsbygdsområdena i Bangladesh

Hossain, Nabil January 2020 (has links)
This study will provide background information about the region of Bangladesh,more specifically the coastal rural area of Bangladesh. This region has due to theglobal warming become a very disaster-prone region where disaster resilience workhas become increasingly relevant. Displacement of the rural coastal population dueto disasters is an ongoing issue in Bangladesh which inhibits the large urbanization the capital city, Dhaka faces. This has increased the need of housing which has stimulated the brick industry that has increased its contribution to BangladeshGDP the last years. Though the brick industry has traditionally been dominated by environmentally unfriendly methods that has caused deforestation and severe air pollution contributing to the cause of its demand creating a negative feedbackloop. This study will analyse four different building materials including the tradition alone by collecting data, creating analyse models and discussing them to find a more financial, environmental and technical suitable alternative to respondto the current situation to try turn the tide focusing on the rural coastal areas of Bangladesh.
24

Från slott till koja : En studie av det svenska murteglets historia / From Castle to Cottage : A Study of the History of Swedish Bricks

Johansson, Frida January 2017 (has links)
Det svenska murteglets historia har inte tidigare sammanställts med en bredd över tid och rum. Uppsatsen är skriven i syfte att lägga det historiska pussel som kan berätta hur teglet har använts, vem som har använt det och hur det har förändrats i utseende genom århundradena. Detta har gjorts främst genom litteraturstudier, där källorna sträckt sig över en tidsperiod av 2000 år. Bitar ur varje källa har plockats ut och sedan pusslats ihop för att ge en kronologisk bild över historien. Bilden som trädde fram visade hur katolska munkar tog teglet till Sverige. Det dröjde sedan inte länge förrän kronan och kyrkan också började använda sig av materialet. Först på 1700-talet, tack vare husförhörssystemet som gjorde så att seklets barn lärde sig att läsa, fick teglet sitt genomslag då instruktionsböcker skrevs och spreds över landet. På 1870-talet blev tegelindustrin mekaniserad i stor utsträckning, vilket gjorde branschen känslig för svängningar i landets ekonomi. Utifrån detta dras slutsatsen att läskunnigheten och industrialismen inneburit de största blomstringsperioderna i teglets historia. Ironiskt nog innebar också industrialismen teglets fall, dels genom ekonomisk känslighet, dels genom att betongen tilläts ta över. / The complete history of Swedish bricks has not yet been fully compiled. This paper is written with the intention to assemble the historic puzzle which can tell the story of how bricks have been used, who has used them and how their appearance has changed over the course of time. To do this, extensive literature studies have been made, with sources stretching over a period of 2000 years. Bits of each source have been taken to create a chronological picture of its history. The results showed that catholic monks took the knowledge of brick working to Sweden in the 12th century. Soon, the royal power and the church started using brick as well. Despite this, bricks did not get its biggest breakthrough until the 18th century, when a new church law made children learn how to read. Instruction books got released and were read by a fairly large portion of the Swedish population. In the 1870s, the brickyard industry got mechanized, which made the branch sensitive to changes in the country’s economy. From this, the conclusion is drawn that literacy rate and industrial revolution led to the two biggest blooms in the history of bricks. Ironically, the industrial revolution also lead to the descent of the brick industry, partly because of the economic sensitivity, partly because the concrete was allowed to take over.
25

Byggmaterialens livscykel : En analys om hur miljön påverkas under ett byggprojekt

Johar, Selman, Tofik, Hedi January 2021 (has links)
Problem background: During a construction project, the environment is negatively affected due to all construction waste that occurs. Even during the manufacture of building materials, the environment is affected. Construction waste in Sweden is about 31 percent, it is quite high, but they are constantly trying to reduce construction waste and the environmental impact that the construction sector is responsible for. The construction waste that takes place has a direct connection to building materials, which also has a direct connection to the carbon dioxide emission in the production of these building materials. Therefore, in this work we have addressed these three points that focus on the environmental impact that the construction industry has in a construction project. The purpose of the work is to investigate how the construction industry affects the environment. Because it is a complicated industry where a lot happens. For example, there are several different types of transport both from and to the construction site that leads to increased carbon dioxide emissions. To reduce construction waste, you must have the knowledge as to know why construction waste occurs and be able to apply the waste hierarchy during a construction project for reduced environmental impact. The methodology for completing this work was due to various scientific articles and literature studies used, via Mälardalens University's library database. In addition, some interviews were conducted that helped strengthen and complete the work. The interviews provided different views and perspectives and explained in detail how construction waste is handled during a construction project. The survey provided a better insight into how this is done, handled and what solutions are available to reduce the construction sector's environmental impact during a construction project. The end results of the work showed that there are some methods you can use to reduce the environmental impact that the construction industry has today. With these methods, it is not only the environment that has a positive effect but also the construction company because it leads to lower costs and more efficient construction methods. The results also showed that the construction industry is a complicated industry where a lot affects each other and that they always try to reduce their environmental impact by constantly striving for their environmental goals. The Conclusions of the work is that the environment affects the construction industry in different ways. Everyone involved is trying to reduce their influence, but there are some challenges that exists and should be addressed. The work highlights the problem and alternative solutions that the construction industry can use to reduce their environmental impact.
26

Hållbar utformning av en offentlig toalettbyggnad genom återbruk / Sustainable design of a public toilet building through reuse

Sandin, Cecilia, Holgersson, Mindy January 2023 (has links)
Today, the construction and property sector accounts for close to 40% of the global climate emissions. In Sweden, the waste from the construction industry is almost half of the total waste. That is a major problem and people need to get more aware of and increase the reuse, recycling and circular economy to reduce the climate footprint. The purpose of the study is to establish which materials can be reused to construct a public toilet building. A study has been made to illustrate if a building can be built in only reused materials and products. The goal is thereby to present an illustrated public toilet building with the materials that can be used to construct the building. The goal is also to display obstacles when building with only reused products. Through the use of a case study a public toilet building was designed to be placed in a fairytale world constructed by Aktiebolaget Boll & Stropp. Some of the materials that can be and is reused in the building is brick, glass, wood and procelain products. This case study has proven that it is to a high degree possible to build a public toilet in only reused materials.
27

Byggandets största bidragande faktorer på klimatpåverkan under byggskedet (A1-A5) för ett flerbostadshus i betong

Tieu, Jimmy, Hansson, Niclas January 2021 (has links)
For the past year’s climate change has been a hot topic for the world leaders and organizations, with discussions regarding how to reduce the environmental impact. The construction- and real estate sector are responsible for majority of the greenhouse emissions and other pollutants that affects the global climate. The energy consumption from operational phase has long been the main cause to the environmental impact but lately studies and research has brought increasedattention to the fact that the construction phase may have a greater significant to a building’sclimate impact.The purpose of this study is to investigate and identify the key factors and building parts that contributes the most to greenhouse emissions for the residential building during the construction phase. The results that are presented is based on life cycle analysis data (LCA) and calculated with a LCA tool called Byggsektorns miljöberäkningsverktyg (BM 1.0) from IVL.The conclusions this paper presents is that the product phase stands for most of the environmental impact during the construction phase with material as the key contributor. It shows that the choice of materials and products plays a crucial role for a buildings total impact. Transport and construction production have a minor impact compared with the product phase.
28

Chemical emissions from building structures : emission sources and their impact on indoor air / Kemiska emissioner från byggnadskonstruktioner : källor till emissioner och deras påverkan på inomhusluften

Glader, Annika January 2012 (has links)
Chemical compounds in indoor air can adversely affect our comfort and health. However, in most cases there is only a limited amount of information available that can be used to assess their health risk. Instead the precautionary principle is often applied, i.e. efforts are made to ensure that the concentrations of pollutants are kept at a minimum when constructing new buildings or conducting renovations by using low-emitting building materials. Today, when investigating buildings in order to solve indoor air quality problems, volatile organic compounds (VOCs) are sampled in the air within rooms. The chemical composition of indoor air is complex and there are many sources for the chemicals present. The potential for emissions from sources in hidden spaces such as wall cavities is poorly understood and little information exists on the toxic potential of chemical releases resulting from moisture-related degradation of building materials. Most of the non-reactive VOCs that have been detected in indoor air in field studies and from building products are not believed to cause health problems. However, reactive compounds and chemical reaction products have the potential to negatively influence our comfort and health even at low concentrations. Even though the impact of chemical compounds on health is unclear in many cases, they can be used to identify technical problems in buildings. When a building is investigated, the air inside building structures could be sampled. This method would eliminate emissions from sources other than the construction materials and the samples would contain higher levels of individual compounds. The aims of this work was to identify emissions profiles for different types of building structures, to see if the emission profiles for moisture damaged and undamaged structures differed, and to determine whether any of the emissions profiles for specific structures also could be found in indoor air. Technical investigations and VOC sampling were performed in 21 different buildings with and without previous moisture damage. Seven of the buildings were investigated in the years 2005-2006 (study 1) and fourteen in the years 2009-2010 (study 2). In study 1, sixty samples were analyzed by PCA at the chemical group level (18 chemical groups, i.e. aldehydes, ketones etc). 41 % of all identified chemical compounds belonged to the hydrocarbon chemical group. The second largest chemical groups, each of which accounted for 5-10 % of all identified compounds, were alcohols, aldehydes, ketones, polyaromatic hydrocarbons (PAHs) and terpenes. The results indicated that one of the main factors that determined the emissions profile of a building structure was the materials used in its construction. Notably, concrete and wooden structures were found to have different emissions profiles. The sum of VOC (TVOC) concentrations for all 241 samples from both study 1 and study 2 was used to compare total emissions between different building elements (ground and higher floors, external walls and roof spaces). Most building elements exhibited relatively low emissions compared to concrete ground floors, which generally had higher TVOC emissions. Emissions from both polystyrene insulation and PVC flooring could be identified in concrete ground floors and were the main cause for the higher emissions found in these structures. Profiles for wood preservatives such as creosote and pentachlorophenol were also identified in external walls. The emission profiles found in the structures could not be identified in the indoor air in the adjacent rooms, although individual compounds were sometimes detected at low concentrations. Our results showed that the main factors influencing emissions in building structures were the construction materials and the nature of the building element in question. Because of difficulties with finding active water damage at the times of sampling and because of sampling inside closed building structures with old dried-out moisture damages, the field method used in this work was unsuitable for identifying differences in emission profiles between moisture damaged and undamaged structures. It will thus be necessary to investigate this difference in a laboratory where the precise composition of all tested structures is known, a range of RH values can be tested and the accumulation of emissions can be followed. / Kompetenscentrum Byggnad - Luftkvalitet - Hälsa 2 (KLUCK 2)
29

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.
30

Framtidens klimatvänliga bindemedel i betong : En analys av naturliga puzzolaner som tillsatsmaterial / Future climate-friendly binders in concrete : An analysis of natural pozzolans as supplementary cementitious materials

Sjödin, Sabine, Fredin, Elsa January 2023 (has links)
Betong är ett av världens mest använda byggnadsmaterial, men kan också vara en stor miljöbov. Cementklinker är en betydande beståndsdel i betong som vid tillverkning frigör stora mängder koldioxid, av den anledningen optimeras betongrecept idag genom att ersätta en del av cementen med flygaska som är en restprodukt från kolkraftsindustrin. I takt med att samhället rör sig mot en fossilfri produktion beräknas tillgången till flygaska att avta och material med liknande egenskaper undersöks som alternativa bindemedel i betong.  Syftet med studien är att, genom litteraturstudier och laboratoriska tester, undersöka huruvida naturliga puzzolaner kan ersätta mängden flygaska i en cementsammansättning utan att försämra betongens hållfasthetsegenskaper. Tryckhållfastheten samt hållfasthetsutvecklingen har undersökts hos 150x150x150 mm provkuber med varierande mängd flygaska samt vulkanaska av isländsk pimpsten respektive jordanska tuffer. Målet med studien är att minska mängden, eller helst ersätta hela andelen flygaska i en klimatförbättrad betongsammansättning.  De laboratoriska testerna har utförts enligt svensk standard där totalt 48 provkroppar gjutits. Referenskuben i undersökningen består av 80% portlandkalkstencement och 20% flygaska. Totalt har 6 olika kombinationer av provkuber gjutits där andelen flygaska ersätts med 20%, 15% eller 10% vulkanaska. Vardera provkub har utsatts för tryckhållfasthetsmätning efter 2, 7 samt 28 dygn.  Resultatet av provtryckningen visade att provkuberna innehållande isländsk pimpsten gav en ökad eller oförändrad hållfasthet vid samtliga mätningar, jämfört med referenskuben. Provkuberna innehållande jordanska tuffer medförde däremot en reducering av hållfastheten vid samtliga mätningar, jämfört med referenskuben. Provkuberna innehållande vulkanaska från isländsk pimpsten gav högst sluthållfasthet då ingen flygaska förekom i sammansättningen och något sämre värden vid inblandning av flygaska, till skillnad från provkuberna innehållande vulkanaska från jordanska tuffer som utan flygaska i princip stannade av i sin hållfasthetstillväxt efter 7 dygn. Skillnaden i resultatet mellan vulkanaska av pimpsten respektive tuffer antyder att vilken typ av material det är samt dess ursprung har betydelse för hur det presterar som bindemedel i betong. / Concrete is one of the most widely used building materials in the world, but it can also be a major environmental culprit. Cement clinker is a significant component of concrete that releases large amounts of carbon dioxide during production. For this reason, concrete recipes are now optimized by replacing some of the cement with fly ash, which is a byproduct from the coal power industry. As society moves towards fossil-free production, the availability of fly ash is expected to decrease, and materials with similar properties are being investigated as alternative binders in concrete.  The purpose of the study is to investigate, through literature review and laboratory tests, whether natural pozzolans can replace the amount of fly ash in a cement composition without deteriorating the strength properties of the concrete. The compressive strength and strength development have been studied on 150x150x150 mm test cubes with varying amounts of fly ash and volcanic ash from Icelandic pumice and Jordanian tuffs. The goal of the study is to reduce the amount, or preferably replace the entire portion, of fly ash in a climate-improved concrete composition. The laboratory tests have been performed according to Swedish standards, where a total of 48 test specimens have been cast. The reference cube in the study consists of 80% Portland limestone cement and 20% fly ash. A total of 6 different combinations of test cubes have been cast, where the proportion of fly ash is replaced with 20%, 15%, or 10% volcanic ash. Each test cube has been subjected to compressive strength measurement after 2, 7, and 28 days. The results of the compression testing showed that the test cubes containing Icelandic pumice provided increased or unchanged strength at all measurements, compared to the reference cube. However, the test cubes containing Jordanian tuffs resulted in a reduction of strength at all measurements, compared to the reference cube. The test cubes containing volcanic ash from Icelandic pumice provided the highest final strength when no fly ash was present in the composition, and slightly lower values when fly ash was added, unlike the test cubes containing volcanic ash from Jordanian tuffs which essentially plateaued in their strength development after 7 days without fly ash. The difference in results between volcanic ash from pumice and tuffs suggests that the type and origin of the material are significant factors in how they perform as a binder in concrete.

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