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  • 1.
    Andersson, H.
    et al.
    Univ Gavle, Sweden.
    Cehlin, M.
    Univ Gavle, Sweden.
    Moshfegh, Bahram
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering. Univ Gavle, Sweden.
    Experimental and numerical investigations of a new ventilation supply device based on confluent jets2018In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 137, p. 18-33Article in journal (Refereed)
    Abstract [en]

    In developed countries, heating, ventilation, air conditioning (HVAC) systems account for more than 10% of national energy use. The primary function of a HVAC system is to create proper indoor environment. A number of ventilation strategies have been developed to minimize HVAC systems energy use whilst still maintaining a good indoor environment. Among these strategies are confluent jet ventilation and variable air volume. In this study, an air supply device with a novel nozzle design that uses both of the above-mentioned strategies was investigated both experimentally and numerically at three different airflow rates. The results from the numerical investigation using the SST k - omega turbulence model regarding velocities and flow patterns are validated by experimental data carried out by Laser Doppler Anemometry. The results from both studies show that the flow pattern and velocity in each nozzle is directly dependent on the total airflow rate. However, the flow pattern does not vary between the three different airflow rates. The numerical investigation shows that velocity profiles for each nozzle have the same pattern regardless of the airflow rate, but the magnitude of the velocity profile increases as the airflow increases. Thus, a supply device of this kind could be used for variable air volume and produce confluent jets for the airflow rates investigated.

  • 2.
    Andersson, Sonja
    Linköping University, Department of Science and Technology.
    Bostadsanpassningsbidrag i Norrköpings kommun2003Independent thesis Basic level (professional degree)Student thesis
    Abstract [sv]

    Funktionshindrade personer har möjlighet att få sin bostad anpassad så ett de kan leva ett självständigt liv i ett eget boende. Anpassningen betalas av kommunen genom ett bostadsanpassningsbidrag. De senaste åren har, inom Norrköpings kommun, kostnaderna för bostadsanpassningsbidrag ökat kraftigt och överstigit den budget som tilldelats. Syftet med den här rapporten är att undersöka hur andra kommuner arbetar med handläggning och upphandling av bostadsanpassningsärenden. En del frågor rör även åldersfördelningen.

    För att få en uppfattning om hur arbetet med bostadsanpassningsbidrag bedrivs ute i kommunerna har jag valt att göra en enkätundersökning. Kommunerna i undersökningen är valda efter invånarantal, jämförbara med Norrköping. Jämförelsen med andra kommuner visar att i stort sett alla jobbar på samma sätt när det gäller upphandlingar och ersättningsformer. Det går inte att säga att en ersättningsform är mer kostnadseffektiv än en annan när det gäller bostadsanpassningar. Kostnaden per ärende varierar stort hos de olika kommunerna. Jag kan konstatera att Norrköping ligger bland de som har den högsta kostnaden.

    Löpande räkning är den absolut vanligaste ersättningsformen. I ända upp till 90 % av alla ärenden i vissa kommuner används denna ersättningsform. Annars svarar de flesta att de också tillämpar löpande räkning med takpris och fast pris på anbud. Åldersfördelningen ser likadan ut i kommunerna i undersökningen. Genomsnittet av andelen personer över 75 år är 58 % och den överensstämmer med den siffra jag kom fram till i åldersfördelningen för bostadsanpassningsbidrag i Norrköpings kommun. Däremot ligger kostnaden för dessa ärenden något högre i Norrköping. Gemensamt för samtliga tillfrågade är att de anser att det byggs alltför lite anpassade bostäder för äldre. Detta återspeglar sig i ökade kostnader för bostadsanpassningsbidrag. I stora drag arbetar de tillfrågade kommunerna på samma sätt med handläggning av ärenden.

    För att komma tillrätta med de höga kostnaderna för bostadsanpassningsbidrag i Norrköpings kommun krävs att en mer omfattande undersökning görs. Enskilda ärenden skulle behöva jämföras för att se hur andra kommuner har beslutat, handlagt och upphandlat liknande fall.

  • 3.
    Arghand, Taha
    et al.
    Högskolan i Gävle, Energisystem.
    Karimipanah, Taghi
    Högskolan i Gävle, Energisystem.
    Awbi, Hazim
    School of Construction Management and Engineering, University of Reading, United Kingdom.
    Cehlin, Mathias
    Högskolan i Gävle, Energisystem.
    Larsson, Ulf
    Högskolan i Gävle, Energisystem.
    Linden, Elisabet
    Högskolan i Gävle, BMG-labbet.
    An experimental investigation of the flow and comfort parameters for under-floor, confluent jets and mixing ventilation systems in an open-plan office2015In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 92, p. 48-60Article in journal (Refereed)
    Abstract [en]

    There is a new trend to convert the workplaces from individual office rooms to open offices for motivating money saving and better communication. With such a shift the ability of existing ventilation systems in meeting the new requirements is a challenging question for researchers. The available options could have an impact on workers' health in terms of providing acceptable levels of thermalcomfort and indoor air quality. Thus, this experimental investigation focuses on the performances of three different air distribution systems in an open-plan office space. The investigated systems were: mixing ventilation with ceiling-mounted inlets, confluent jets ventilation and underfloor air distribution with straight and curved vanes. Although this represents a small part of our more extensiveexperimental investigation, the results show that all the purposed stratified ventilation systems (CJV and UFAD) were more or less behaving as mixing systems with some tendency for displacement effects. Nevertheless, it is known that the mixing systems have a stable flow pattern but has the disadvantage of mixing contaminated air with the fresh supplied air which may produce lower performance and in worst cases occupants' illness. For the open-plan office we studied here, it will be shown that the new systems are capable of performing better than the conventional mixing systems. As expected, the higher air exchange efficiency in combination with lower local mean age of air for corner-mounted CJV and floor-mounted UFAD grills systems indicates that these systems are suitable for open-plan offices and are to be favored over conventional mixing systems.

  • 4.
    Aronsson, Mattias
    et al.
    Linköping University, Department of Science and Technology.
    Karlsson, Jimmy
    Linköping University, Department of Science and Technology.
    Jämförelse av produktionsmetoder vid byggande av gång- och cykeltunnel.2003Independent thesis Basic level (professional degree)Student thesis
    Abstract [sv]

    Vi har i denna rapport jämfört produktionsmetoder vid byggande av gång- och cykeltunnel under järnväg. de metoder vi har jämfört är lansering och platsgjutning. Projektet som vi har studerat är byggandet av en gong- och cykeltunnel under järnväg vid Mjölby station. Vid detta projekt lanseras halva tunneln in och halva platsgjuts.

    Det vi har jämfört är dels de geotekniska aspekterna, där vi främst har tittat på vikten av förundersökningar, jordegenskapens inverkan, spontning och grundvattnets inverkan. Vi har också tittat på produktionstekniska aspekter, då främst storleken av arbetsområdet och arbetsmiljön. Vi har även betraktat ekonomi och produktionstid i de båda metoderna.

    Vi har i denna rapport främst använt oss av muntliga källor som gett sina synpunkter på hur tunneln ska eller bör utformas. Vi har sedan sammanställt alla synpunkter och åsikter och skaffat oss en egen uppfattning om de båda metoderna och när de bör användas.

    Det vi kommit fram till när vi har jämfört dessa båda metoder är att lansering har många fördelar vad gäller arbetsmiljö, tid och ekonomi. vid enklare tunnelprojekt är denna metod att föredra om förutsättningar finns. platsgjutning har dock de fördelar att den kan användas vid de flesta tunnelbyggnationer och att tågtrafiken kan flyta på utan längre störningar.

    Vid stora projekt som det i Mjölby anser vi att en kombination av metoderna är den allra bästa lösningen.

  • 5.
    Aslan, Jiyan
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Asp, Marcus
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Jointed timber column with glue or nails.2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    På en byggarbetsplats kan man ibland behöva sammansätta två eller flera träkomponenter till en träkomponent med rätt dimension. Det sker oftast genom spikning men det finns också möjlighet att limma ihop träkomponenter ute på en byggarbetsplats. Limning är inte alls lika förekommande på grund av de krav som ställs på limning av bärande konstruktioner och kringliggande miljö varför limning i princip endast sker i fabriksmiljö. I denna studie utförs en jämförelse mellan sammansättning av träreglar till en träpelare med avseende på hållfasthet och ekonomi. Detta jämförs dessutom med att köpa in pelare av trä med rätt dimension. I studien behandlas dessutom möjligheten att limma ute på en byggarbetsplats och hur limningen ska utföras på ett korrekt sätt. Studien har genomförts med hjälp av de standarder som finns för beräkningsregler för dimensionering av bärverk, eurokoder. Kostnadsberäkningar har genomförts för material och utförandearbete med hjälp av marknadspriser för material och enkla beräkningar för utförandearbete. En intervju har genomförts för att besvara möjligheten att limma ute på en byggarbetsplats med lim för bärande konstruktioner. I studien har beräkningar utförts för två samt tre sammansatta träreglar och jämförts med enkla pelare i liknande dimensioner. Spikad pelare har en avsevärt lägre bärförmåga än limmad pelare som är utförd korrekt. Spikad pelare har beräknats med olika avstånd mellan spikar och limmad pelare är beräknad med två olika lim. Kostnaderna för material och utförandearbete är ganska generella men är bara en liten del av de totala kostnaderna. Vart byggarbetsplatsen är placerad, vilka verktyg och material som finns på plats och vilka förutsättningar för att utföra limningen korrekt är faktorer som är avgörande för den totala kostnaden. Ett limförband är känslig och viktigast är att applicera rätt mängd och jämnt utbrett över träytorna. Vad som dessutom ska tas till hänsyn är kringliggande miljö såsom smuts, damm, temperatur och fuktighet. För att uppfylla dessa krav ute på en byggarbetsplats måste en fabriksmiljö skapas i form av väderskydd, tält, arbetsbod eller liknande.

  • 6.
    Atto, Andreas
    Linköping University, Department of Science and Technology.
    Byggprocessen i förändring - Visionen om BIM2011Independent thesis Basic level (professional degree), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The primary purpose of this thesis can be said to be to create a perception at Skanska Civil Southeast, which is the initiator of this thesis, on what BIM (Building Information Model) is and how it can most easily be implemented in their work processes. It would be impossible to cover all aspects of BIM in the short amount of time that has been available and in the context of this thesis, therefore, the aspects that were deemed important to the company and to the author has been picked up for investigation.

    To achieve this, the task of the thesis is to identify and highlight the differences between today's construction process, and BIM (Building Information Model) and from that suggest possible ways to implement this way of working to Skanska Civil Southeast.

    The thesis first chapter provides a brief introduction and background to the construction process and how it has changed over time. A purpose and questions on which the thesis is being based on are formulated and a boundary for the thesis is done.

    The thesis second chapter provides the theoretical background to today's construction process. Key aspects of today's construction process are highlighted and explained. This is followed by a presentation of the concept of BIM and what it means. After that, a brief review of how the work with BIM looks at Skanska Sweden AB and in the construction industry generally.

    The thesis third chapter presents how BIM is currently used on a road project just outside of Katrineholm in a project called Förbifart Katrineholm where BIM is being applied to some extent. The differences that exist between today’s construction process and the BIM and the pros and con that can be observed in BIM relative to today's construction process is presented.

    In the thesis fourth chapter answers the questions and the results are analyzed and discussed on important aspects of construction, to, in the fifth chapter make concrete proposals on how an implementation of BIM in Skanska Civil Southeast work processes may look like.

  • 7.
    Bertilson, Anton
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    The quality of quality controls. A study of the controlls for certifying building according to Miljöbyggnad.2014Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Miljöbyggnadscertifieringarna har ökat markant sen systemet lanserades och allt fler byggnader uppförs i Sverige idag med stort miljöfokus. Men hur bra är kvalitetskontrollerna som ska säkerställa att byggnaden uppfyller certifieringskraven? Denna rapport syftar att svara på hur noggrant kvalitetskontrollerna för certifiering av Miljöbyggnad utförs samt hur bra dessa kontroller är på att säkerställa certifieringen ur ett kvalitetsperspektiv. För att svara på syftet så undersöks och kartläggs det vilka kvalitetskontroller som gjorts på referensobjektet framtidens US i Linköping. Efter att kvalitetskontrollerna kartlagts så har de utvärderas och fått ett betyg efter utvärderingsparametrar som tagits fram i samarbete med energiexpert, kvalitetssamordnare och miljösamordnare. Alla olika typer av kontrollers betyg har lett till ett samlat indikatorbetyg som återspeglar hur bra kontrollerna kring varje indikatorn är på att säkerställa kvalitén på certifieringen. Resultatet ger en spridd bild över hur bra kontrollerna är på att säkerställa kvalitén på certifieringen. Det förekommer höga felmarginaler i kontrollerna och detta leder till ett sämre betyg. Generellt så har indikatorbetygen varit väldigt bra när det gäller att säkerställa kvalitén på certifieringen.

  • 8.
    Björklöf, Sune
    Linköping University, Department of Management and Economics. Linköping University, Faculty of Arts and Sciences.
    Byggbranschens innovationsbenägenhet: En studie om den svenska byggbranschens inställning till innovationer och branschens beredskapatt hantera innovationsfrågor1986Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The attitude of the building sector towards innovation and its intellectual and organizational preparedness for dealing with the issues of innovation is the aim of this study. The core question can be formulated as follows: Why does a building company accept certain innovations but not others? The fundamental ideas of the study are rooted in the central European tradition of the historico-qualitiative school of thought. Another basic idea for the thesis is Dewcy’s and Bcntley's theory of transactional cognition introduced in Sweden by Hanssen under the term ""field concept" according to which the content and object of knowledge are seen as an entirety. The reason for approaching the problem qualitatively. that is through not highly structured interviews based on the author's long personal experience in the sector, is its compound and many face ted nature a long with the fact that verbal discussion is firmly grounded in building sector tradition.

    Innovations has to pass trough three different filters. These filters are at the point where the innovation enters the company, during the bid preparation process and upon the absorption of the innovation into the project. Important factors influencing the passage through these filters arc papyrophobia, the old boy network (OBN) and the structure of the production system. Papyrophobia is expressed in a general reluctance to deal with theoretical issues and documentation. OBN denotes an informal communication network. Production is run by and within project organizations. i.e. repetitive ad hoc aggregates independent of the parent organization. These factors in combination with time and financial pressure obstruct the possibility of creating a research tradition.

    Characteristic features of the socio-cultural tradition of the sector are that it is male dominated, that the educational system classifies those working in the field according to trade and profession, and that the strong position of production aspects have brought to the forefront the energetic practitioner. His values are strictly professional. Information is to a great extent transmitted orally. There is strength in the ability of Swedish construction firms to plan and improvise within an established frame. However, a certain streak of marginalism with the potential of inhibiting innovation does exist in their pattern of action. Also typical of the tradition is the ideal of the free entrepreneur and the organization of large companies as confederations of a number of small and medium size firms. Finally, a fundamental cultural feature of the construction industry is openness. News spreads rapidly to a competitor.

    Innovations are disseminated in several ways, but one dominant pattern persists that cannot be seen in other industries. While the projects are important for testing and diffusion of innovations, the companies arc more intrumental in propagating information of innovations. The building materials industry's R&D work follows a pattern similar to that of production companies in other sectors.

    The building sector's readiness to follow and work with innovation issues can generally be rated as low. The confinement of interest to production aspects combined with the marked open· ness provides ample room for the materials manufacturers and companies outside the sector to introduce new products and materials. In the long run, it is the gradual change in this assortment that will transform building techniques and technology. Change is generated by other sectors.

  • 9.
    Bodin, Gustav
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Jaber, Momamed
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Energiberäkning för påbyggnader2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Saving energy is important both economically and environmentally.

    The way we in Sweden build our houses and the rules that govern our energy usage has varied over the years.

    Åtvidabergstakvåningar is a company that perform superstructures in the shape of new penthouses for villas. Åtvidabergstakvåningar came with the initiative for the study, too get a picture of how the energy usage transformed for villas equipped with their penthouses. They also came with the initiative for the method to create time distinct villas and equip these with their penthouses.

    The study gives a picture of how the building envelop is composed and how the energy loss is through it. The study will also compare how the rules that govern energy loss and usage have transformed over the years.

    The result of the Study is an energy calculation that declares the energy usage for the time distinct villas with and without penthouses.

    The Result of the study shows that the older houses get a better energy performance after adding on the penthouses, while the new house got a value that was similar.

  • 10.
    Boiadjiev, Borislav
    Linköping University, Department of Science and Technology.
    Undersökning av skalväggs egenskaper utan igjutning med betong2006Student paper second term, 10 points / 15 hpStudent thesis
    Abstract [en]

    Double walls normally consist of two concrete shells 45-75 mm thick with an air column them between. The shells in the wall are held together with reinforcement’s bars. The air column even breadth depends on the wall's total thickness and is (cast in place) founded in on-the-spot. The objective with this work is to examine double walls direct properties then the air column is without concreting. If the double walls are found to have good resistance it can begin to be used instead of massive walls.

    The calculations for the resistance are carried out partially with FEM programme (Finite Element method programme) and partially with complementary hand calculations. The calculations for fire dimension ring and acoustic properties are implemented according to simplified calculation methods.

    The results show that double walls directly can to take up a load corresponding to the weight of ten floors. In the reality double walls will not be used as carrying walls and the study is only a survey about how heavy loads the wall principally can carry.

    Weak points in the compound system are the reinforcement bars in the estimated load bearing structure. Their resistance creates the base for dimensioning and the design resistance increases with bigger bar diameter.

    The double walls meet the requirements for fire on minimal thickness and minimal concrete cover layer. According to the calculations the double walls has fire resistance corresponding to 1,5 MN pressures.

    The wall has, in the basis execution, a reduction number on R=45 dB according to the calculations. This can be enough to use them in building parts with lower requirements for air sound isolation.

    The double walls are a” half precast component” that is on the way to become a ”completely precast component”.

    The double walls have according to the calculations good possibilities to replace massive walls and with possible completions for fire - and sound isolation can the usage be increased.

  • 11.
    Bondarevs, Andrejs
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Huss, Patrik
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Gong, Shaofang
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Weister, Ola
    Vertical Plants System Sweden AB.
    Liljedahl, Roger
    Vertical Plants System Sweden AB.
    Green walls utilizing Internet of Thing2015In: Sensors & Transducers Journal, ISSN 2306-8515, E-ISSN 1726-5479, Vol. 192, no 9, p. 16-21Article in journal (Refereed)
    Abstract [en]

    A wireless sensor network was used to automatically control the life-support equipment of a green wall and to measure its influence on the air quality. Temperature, relative humidity, particulate matter, volatile organic compound and carbon dioxide were monitored during different tests. Green wall performance on improving the air quality and the influence of the air flow through the green wall on its performance were studied. The experimental results show that the green wall is effective to absorb particulate matter and volatile organic compound. The air flow through the green wall significantly increases the performance. The built-in fan increases the absorption rate of particulate matter by 8 times and that of formaldehyde by 3 times.

  • 12.
    Borg, Andreas
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Karlsson, Christopher
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    A study of air leakage around window constructions2015Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Det finns flera kritiska punkter i en byggnad där luft kan ta sig in, exempelvis genomföringar i klimatskalet för elrör och vattenrör, anslutningar i klimatskalet i form av dörrar och fönster samt skarvar i byggandens tätskikt. Tätningen kring just fönster är en av de detaljer som det tilldelas mest resurser till. Två grundläggande moment är avgörande för hur stort luftläckage det kan bli; hur tätskiktet avslutas kring fönsteröppningen och vilken tätningsprincip som används. Med detta som en grund har syftet med den här studien varit att ta fram vilka fler parametrar kring en fönsterkonstruktion som är avgörande för dess lufttäthet samt vilka olika typer av tätningsmetoder det finns. Rapporten har tagits fram genom en litteratur- och fältstudie tillsammans med möten med personer i branschen.

  • 13.
    Dahlqvist, Thomas
    et al.
    Linköping University, Department of Science and Technology.
    Parbrand, Mårten
    Linköping University, Department of Science and Technology.
    Dataprogram för beräkning av pålfundament och felslagning av pålar2002Independent thesis Basic level (professional degree)Student thesis
    Abstract [sv]

    Syftet med detta examensarbete är att producera ett dataprogram som dimensionerar pålfundament samt beräknar felslagning av pålar. Ett pålfundaments funktion är att via pålar överföra laster till berg eller fasta jordlager. Felslagning inträffar då pålar inte hamnat på rätt koordinater eller glidit snett ned i marken och ej kan användas. Med hjälp av felslagningsprogrammet erhålles nya påkoordinater för nästkommande påle, vilken måste placeras ut så att tyngdpunkten för hela pålsystemet skall hamna rätt. Programmeringsspråket vi använt oss av är Visual Basic, där vi har omvandlat teoretiska beräkningar till databeräkningar. Detta har resulterat i ett dataprogram som beräknar 2-, 3- och 4-pålsfundament samt tar fram en ny påles koordinater vid felslagning. Vid beräkning av pålfundament tas hänsyn till armeringsmängd, förankring, sprickbildning samt spjälkning.

  • 14.
    Davidsson, Sara
    et al.
    Linköping University, Department of Science and Technology.
    Bagger, Conny
    Linköping University, Department of Science and Technology.
    Lufttäta byggnader2010Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The viscosity of air buildings is a hot topic within the construction performers, which the industry feel they have too little knowledge about. This study is mainly aimed against air density in apartment buildings and airflow measurement. The study consists of a theoretical reference, educational visit, interviews and a survey conducted among construction workers at Magistratshagen in Linkoping.

    Earlier requirement in terms of air leakage through the climate screen was removed and today there are only energy requirement for a dwelling in Boverkets Building Regulations. The difference between a passive and a typical air tight construction is that the passive house have a maximum requirement of 0.3 l /s m2 of air leakage through the building climate screen. The requirement imposed on passive houses is to minimize the supply of power and energy for heating the building.

    Air tight constructions have heavy demands on the performance and accuracy of everyone involved with the project. The client must specify their requirements and also be prepared to pay for any additional costs. The architect and building planners have to design the building with regard to air tightness. Finally, the construction workers are required to do a careful work in order to get all the connections in the building air tight.

    The study suggests that an air tight building is a closed system where no forced ventilation exists. There are no reasons not to build too tight as long as there is a functioning ventilation. In this study the authors ask themselves how an air tight building changes over time. No theoretical information has been found on these changes, but the respondents assume that air density decreases with time. The deterioration is mainly assumed to be caused by construction materials changes over time. The study shows that construction workers knowledge of air tight construction is mixed, which they themselves admit in the survey.

  • 15.
    Destino, Maló
    Linköping University, Department of Science and Technology.
    Kartläggning av behovet av bärighetshöjande åtgärder på mindre vägar2002Independent thesis Basic level (professional degree)Student thesis
    Abstract [sv]

    Detta examensarbete är utfört på uppdrag av Vägverket Region Syd. Sveriges vägnät håller på att anpassas till den europeiska standarden, men det finns fortfarande en hel del begränsningar kvar på mindre vägar. Vi har inte tillräcklig kunskap om vilka problem dessa begränsningar medför för tunga transporter och Vägverket är angeläget om att klarlägga, vilken nytta det skulle vara att göra förstärkningsåtgärder.

    Jag har undersökt ett landsbygdsområde i södra Östergötland och de begränsningar som finns här på flera vägar är dålig bärighet i första hand för broarna och hög tjälfarlighet. Syftet med undersökningen är att göra en kartläggning av de tunga godstransporterna och de problem begränsningarna på vägarna medför för näringslivet. Jag har använt både teoretiska och empiriska studier. De teoretiska studierna kan delas in i:

    - Allmänna tekniska beskrivningar för vägkonstruktioner

    - Lagar och bestämmelser för tunga fordon

    - Information och rapporter från Vägverket

    - Tidigare utförda undersökningar

    De empiriska studierna har utgjorts av intervjuer med olika transportörer i området. Intervjuerna har utförts för att få en bild av hur transportörerna uppfattar vägnätets begränsningar och hur detta påverkar deras verksamhet både praktiskt och ekonomiskt. Jag har intervjuat både stora företag som Södra Skog, Arla och Odal och mindre åkeriägare med ett fåtal lastbilar.

    Mina slutsatser är följande:

    1. Det är fyra vägar i det undersökta området som bör prioriteras när det gäller förstärkningsåtgärder och tjälsäkring.

    2. Vägverket bör undersöka möjligheterna att säkerställa en lätt och smidig kontakt mellan transportörer och de som ansvarar för underhållet av vägarna.

    3. Det verkar vara bättre hålla kvar de mindre grusvägar som finns kvar och underhålla dem bättre med hyvling, grus och eventuellt dikning i stället för att lägga en tunn asfaltbeläggning, som är mycket känslig för tung trafik och tjällossning.

  • 16.
    Egerud, Rebecca
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Södergren, Erik
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Cost differences between Miljöbyggnad Guld and BBR2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Denna rapport är en jämförelse mellan BBR och Miljöbyggnad nivå Guld. Tre frågeställningar besvaras, Vad är skillanden mellan BBR och Miljöbyggnad nivå guld, vad är mervärdet och merkostnaden av Miljöbyggnad nivå Guld. Studien är utförd på en fallstudie av Studenthuset som byggs på Linköpings Universitet. Resultaten av studien visar att skillanderna mellan de två är stora, mervärdet för Miljöbyggnad nivå Guld är stort samt att merkostnaden är 2.5 - 3.0 % för Miljöbyggnad nivå GUld

  • 17.
    Eriksson, Per-Erik
    et al.
    Sveriges Tekniska Forskningsinstitut, Hållbar samhällsbyggnad.
    Nord, Tomas
    Linköping University, Department of Management and Engineering, Industrial Economics. Linköping University, Faculty of Science & Engineering.
    Östman, Birgit
    Sveriges Tekniska Forskningsinstitut, Hållbar samhällsbyggnad.
    Kartläggning av brandincidener i flervåningshus med trästomme: Erfarenhet av 20 års brukande2016Report (Other academic)
    Abstract [en]

    The analysis in this project shows that modern multi-story wooden buildings for housing exhibit a lower fire incident rate than the rest of the multi-family housing stock. This is not surprising since the studied buildings are relatively new. Only one of the incidents in the total of more than 10,000 homes have any connection to the structural material.

    In recent years, the question of fire safety of modern wood construction has been raised from new perspectives. The applied technology for 20 years has been based on the fire safety requirements in the national building code (based on EU:s Construction Products Directive), largely validated through laboratory tests. When the construction technology is now recognized and is expected to increase significantly, the requirement for an evaluation of its function in the real world comes from many actors. This report presents the experiences from built projects in use.

    Modern wood construction is defined in this project as apartment buildings higher than two storeys, where the load-bearing structural material is wood, according to the revised Swedish building regulations in 1994 or later versions. All apartment buildings, including student housing and assisted living, have been included. The project has completed and analysed a total inventory of these homes.

    Data has been collected directly from the component manufacturing companies, developers and contractors who manufactured and erected apartment buildings with more than two stories since 1994. The Swedish Civil Contingencies Agency (MSB) has delivered extracts from its incident database of fire incidents for all of these buildings.

    Data is thus available on more than 10,000 apartments from 188 construction project, which is estimated to represent more than 95 % of completed projects. Respondents in the industry is reporting a total of 3 cases of fire incidents for the years from 1998 to 2014 and the MSB data expands the number with minor incidents to a total of 22 cases for these years, three of which were in separate garbage buildings.

  • 18.
    Eriksson, Sara
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Reslan, Sara
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Practical study to prevent collapse against earthquakes2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Indonesien ligger i Indiska Oceanen och består av ett flertal öar. Landet ligger nära stora tektoniska plattor som tenderar att röra på sig. Det är därför en väldigt stor risk att jordbävningar inträffar i Indonesien. I dagsläget vet man inte varför plattorna rör på sig eller när det kommer att ske.Jordbävningar av hög kaliber är sällsynta och det är praktiskt omöjligt att dimensionera byggnader mot sådana skalv. När konstruktioner tas fram för att bygga jordbävningsresistent är grundidén att byggnader ska tåla måttliga skalv. För att undersöka hur byggnationen ser ut i Indonesien utfördes fältundersökningar samt ett volontärarbete på plats genom organisationen Green Lion. Studien syftar till att hitta enkla lösningar för att få en mer jordbävningsresistent byggnad. För att en byggnad ska ha en stor chans att klara sig måste material med bra töjningsegenskaper användas, armering av stål har sådana egenskaper. En annan viktig åtgärd är att bygga konstruktionen sammanhängande så att de olika elementen stöttar upp varandra när byggnaden utsätts för krafter.

  • 19.
    Frick, Jesper
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Osman, Aweys Mohamed
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Homebuyers choices and valuations2015Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Det finns en generellt god kunskap inom byggnadsbranschen om vilka lägen och byggnadsformer som värderas högst hos bostadsköpare i Sverige. Byggnadsbranschen har dock inte lika bra kunskaper om vad som är att föredra inom bostaden i fråga eftersom dessa värderingar ändrar sig snabbt med tiden. Vilka värderingar har egentligen bostadsköpare när det kommer till bostadens konstruktion, funktionalitet och utformning? Svaret på denna fråga skulle gynna både företagen och bostadsköpare. Syftet med denna studie är just att besvara denna fråga med begränsning till flerbostadshus. Syftet är också att ta reda på hur konstruktionslösningar på en högre nivå än standard påverkar bostadsköparens vilja att betala mer för bostaden. Examensarbetet bygger på en förfrågan av Botrygg AB som vill veta mer om vad bostadsköpare har för värderingar och vilka val de gör om de kan påverka bostaden. För att uppfylla syftet har en kvantitativ studie genomförts där resultatet baseras på en enkätundersökning. Enkäten bestod av tydligt formulerade fleralternativs frågor där den svarande fick värdera olika påståenden och konstruktionslösningar. För att skapa enkäten har en djupare litteraturstudie genomförts. Enkäten visar en mängd intressanta resultat bland annat att bostadsköpare gärna har möjlighet att påverka sin framtida bostad, vare sig det handlar om innan de flyttat in eller efter. Bostadens utformning och planlösning är viktigare än bostadsytan och priset, där det även är tydligt att en öppen eller halvöppen planlösning är att föredra. Det viktigaste med bostadens kök är att det är utformat med fokus på arbetsyta och förvaring. Konstruktionslösningar med högre nivå än standard ökar generellt viljan att betala mer för bostaden, men eftersom svaren skiljer sig mycket handlar det mer om att hitta rätt köpare än en lösning som passar alla. De svarande uttrycker också att det som de är mest nöjda med i sin nuvarande bostad är att den är genomförd med hög konstruktionskvalitet.

  • 20.
    Fällman, Alexander
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Yngve, Max
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Passive house year round2015Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Passivhus är idag populära bostäder med tyngdpunkt på låg energianvändning. En kravspecifikation, FEBY 12, ställer ett flertal krav på passivhus, däribland energianvändning för uppvärmning. Ett välisolerat och tätt klimatskal är därför en förutsättning för passivhuset att kunna uppfylla kraven. Denna rapport behandlar fönster, som är en del av klimatskalet, och dess påverkan på det termiska inomhusklimatet. Studien genomfördes genom simuleringar i datorprogrammet ParaSol. I det första steget jämfördes fönsterarea, g-värde, u-värde, orientering samt geografisk plats för att undersöka hur energianvändningen förändrades. Resultateten presenteras med diagram och i ett senare avsnitt även slutsatser. Detta tillämpas med ett exempelhus som placeras i Lund, Stockholm och Luleå. Med hjälp av fönsterareor och fönsteregenskaper optimeras energianvändningen för uppvärmningen så att husen uppfyller kraven i FEBY 12. Fönsterareornas storlek behöver anpassas till den geografiska positionen för att uppnå en optimal energianvändning för uppvärmning. I studien fick vi fram att fönsterareorna, utan solavskärmning, i Lund kunde utgöra 16 % av fasaden, i Stockholm 13 % av fasaden och i Luleå 11 % av fasaden. Med solavskärmning blev fönsterareorna något större, detta medförde också en något större energiförbrukning.

  • 21.
    Glad, Wiktoria
    Linköping University, Department of Thematic Studies, Technology and Social Change. Linköping University, Faculty of Arts and Sciences.
    Everyday governance of energy systems2017In: Procedia Engineering, ISSN 1877-7058, E-ISSN 1877-7058, Vol. 180, p. 1612-1621Article in journal (Refereed)
    Abstract [en]

    The proposed transition to a low-carbon society faces challenges, as it is occurring too slowly to achieve the goals set by international and national governmental bodies, and gaps are found between available energy-efficiency technologies and their appropriate use. The governance of domestic energy systems has attracted European research attention, and the findings illustrate how materials, competence, and meaning influence energy productivity in domestic settings and how accountability is enacted by connecting people and technologies. The present research cites Swedish examples of how energy efficiency has been improved by involving multiple local actors, such as consumers, energy utilities, property companies, and local governments. Examples are analysed through the lens of social change and mundane governance theory, illustrating how spaces and places often overlooked as too mundane to be considered in policy prove, when analysed in more detail, to be important for energy efficiency. The results indicate that “governance pairs” (e.g., “households/lighting” and “caretakers/heating systems”) are more or less successfully held together and influence accountability and governance possibilities. The present analyses demonstrate that, while governance is often portrayed in terms of causality, everyday practices involving governance pairs are messier and less predictable than anticipated. These results call for the upgrading of research into everyday life and for bottom–up approaches to energy studies. Accountability – crucial to closing the energy-efficiency gap and understood in the context of mundane governance – can advance our energy-efficiency thinking and action.

  • 22.
    Gustafsson, Lena
    Linköping University, Department of Science and Technology.
    Rostskyddssystem för stålprofiler: Tekniska egenskaper, ekonomi och miljöfrågor2004Independent thesis Basic level (professional degree)Student thesis
    Abstract [sv]

    Nästan alla stålkonstruktioner måste rostskyddas. Undantaget är de som står inomhus i torr luft. Ett rostskydd kan utföras på flera olika sätt, men de vanligaste är att stålet målas med rostskyddsfärg eller att det varmförzinkas. Innan detta kan utföras måste stålet förbehandlas. Det är viktigt att den utförs noggrant för annars kan kvarvarande föroreningar börja rosta under färg- eller zinkskiktet. Rapporten behandlar de ovan nämnda metoderna, dess egenskaper och miljöpåverkan samt kostnader för systemen.

    De rostskyddsmetoder som används har alla en negativ påverkan på naturen och hälsan. Hur stor den är beror på vilken sorts beläggning som används. Men man måste också tänka på att de faktiskt skyddar stålet och ökar livslängden och därigenom ger ett bättre resursutnyttjande.

    Att säga hur mycket ett system kostar är inte helt lätt. Dessa kostnader beror på flera saker. Den största skillnaden gör mängden stål, men det beror även på till exempel tjocklek och typ av skikt.

    Resultatet av studien är ett antal tabeller där konstruktörerna själva kan gå in och välja det system som, med tanke på ekonomi och miljöfrågor samt skiktets egenskaper, passar bäst till konstruktionen. Även ett snabbvalssystem har utvecklats där man väljer enbart efter en kategori, till exempel den billigaste eller den starkaste.

  • 23.
    Hagman, Oliver
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Johansson, Erik
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Dimensioning aids for nail and screw joints2015Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    I Sverige idag används trä som byggnadsmaterial i stor utsträckning, 90 % av alla enfamiljshus som byggs idag är byggda med trämaterial. Vid sammanfogning av olika träelement används olika förbandstyper. Förbanden som används idag är: Spikförband, Skruvförband, Träskruvförband, Tandbrickor, Spikplåt Syftet med arbetet är att undersöka möjligheten, samt att skapa ett dimensioneringshjälpmedel för träförband som kan underlätta dimensioneringsgången. En genomgång hur beräkningsgången ser ut enligt Eurokod 5 som är den rådande standarden för dimensionering av träförband. Arbetet kommer undersöka hur det olika parametrarna som ingår i dimensioneringsberäkningarna påverkar förbandets tvärkraftsbärförmåga. Tester har utförts på förband med förbindare av räfflad trådspik och laskar av trä. Enligt testerna visade det sig att det enskäriga förbandet hade en högre tvärkraftsbärförmåga än vad det tvåskäriga förbandet, i det fallet då man utformar det enskäriga förbandet med laskar på båda sidorna och har en förskjutning av förbindarna sinsemellan. Den parameter som påverkar tvärkraftsbärförmågan i beräkningsformlerna enligt Eurokod 5 har efter undersökning kommit fram till att det är spikens diameter som ger störst utslag på den dimensionerande tvärkraftsbärförmågan för förbandet.

  • 24.
    Hassan, Osama
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    A Simplified Procedure to Determine the Deflection of Statically Indeterminate Structures2014In: International Journal of Aerospace and Lightweight Structures, ISSN 2010-4286, Vol. 4, no 4, p. 241-253Article in journal (Refereed)
    Abstract [en]

    In the study presented here, the problem of calculating deflection of stati-cally indeterminate continuous beams and structural frames is addressed. Theelastic line equation, taught in many standard courses in structural mechan-ics is used to determine the structure deflections.In the investigated method,the structure is divided into a simply supported members in which the elas-tic line equation is applied to calculate the deflection shape of the structure.The results are compared with the finite element method (FEM) and goodagreement is obtained. Moreover, the advantage of this method is that it issimplified, general, not time-consuming, and it can be standardised to thistype of structures.

  • 25. Hassan, Osama
    A simplified structural analysis of statically indeterminate continuous thick beams2016In: International Journal of Mechanical Engineering Education, ISSN 0306-4190, E-ISSN 2050-4586, ISSN 0306-4190, Vol. 44, no 4, p. 257-271Article in journal (Refereed)
    Abstract [en]

    In the study presented here, a simplified exact analytical solution of the problem of indeterminate continuous beams is derived and compared with the numerical solution, finite element. For the analytical method, the structure is divided into a simply supported element with internal support moments. The moments are first calculated with the help of boundary rotation conditions by taking into account both the shear andbending deformations. Second, the deflection functions of the beam members are derived. The results of a two-span continuous beam show that both methods yield an excellent agreement. The advantage of the presented method is that it is simplified, general, not time-consuming, and it can be standardized to this type of structures. Solution methods discussed in this paper can be of interest within the framework of mechanical and civil engineering education in which bending and shear of thick beamsare taught.

  • 26.
    Hassan, Osama
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Practical expressions to calculate the main vertical actions onload-bearing columns/walls to Eurocode2017In: Journal of Engineering, Design and Technology, ISSN 1726-0531, E-ISSN 1758-8901, Vol. 15, no 7, p. 418-435Article in journal (Refereed)
    Abstract [en]

    Purpose – The aim of this review study is to present useful and practical expressions to compute the design vertical actions on load-bearing columns/walls of typical building structures on the basis of EN 1991: Eurocode 1.

    Design/methodology/approach – It is derived by a typical case in which wind actions, snow actions and permanents actions are loading a roof construction. The results are finally used to calculate the loading on columns/walls. Both ultimate limit state and serviceability limit state are considered.

    Findings – From an instructive point of view, the advantage of this method is that it is simplified, general, not time-consuming, and it can be standardised to typical building structures.

    Research limitations/implications – A number of example applications are introduced to illustrate the calculation procedure.

    Practical implications – From an educational point of view, this problem is of interest to civil engineering students because the reviewed method is not cumbersome or time-consuming.

    Social implications – From an engineering educational point of view, this problem is of interest to civil engineering students because the reviewed method is not cumbersome or time-consuming.

    Originality/value – New formulated expressions to calculate the loadings on structural membranes based on Eurocode are presented.

  • 27.
    Hassan, Osama A.B.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Effect of foundation designs of passive house on the thermal bridges at the ground2016In: Journal of Engineering, Design and Technology, ISSN 1726-0531, E-ISSN 1758-8901, Vol. 14, no 4, p. 602-613Article in journal (Refereed)
    Abstract [en]

    In this paper it is attempted to study the effect of different foundation designs of passive house on the resultant thermal bridges, at the junction between a wall and a slab on grade. The linear thermal transmittances of some newly developed foundations of passive house are determined. The compared foundation designs are L-element, U-element and foundation with foam glass technique. It is found that the special design of passive house foundation can considerably influence the heat flow through thermal bridges. The calculated linear thermaltransmittances of L-element, U- element and foundation with foam glass are 0.085 W/mK, 0.074 W/mK and 0.031 W/mK, respectively. In this context, it is proposed a new foundation design of passive house, which has relatively low heat loss through thermal bridges, calculated as 0.031 W/mK. The results are compared with the “default” ISO values used to evaluate the effect of thermal bridges in typical buildings. It is found that there is large difference between the calculated linear thermal transmittances at the investigated foundationsof passive house as compared to typical buildings.

  • 28.
    Hassan, Osama
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Christopher, Johansson
    Byggprojektering, WSP Sverige AB, Linköping, Sweden.
    Glued laminated timber and steel beams: A comparative study of structural design, economic and environmental consequences2018In: Journal of Engineering, Design and Technology, ISSN 1726-0531, E-ISSN 1758-8901Article in journal (Refereed)
    Abstract [en]

    Purpose – This paper compares glued laminated timber and steel beams with respect to structural design, manufacturing and assembly costs, and the amount of greenhouse gas emissions.

    Design/methodology/approach – This paper presents structural design requirements in conformance with EN 1993: Eurocode 5 and Eurocode 3. With the help of these standards, expressions are derived to evaluate the design criteria of the beams. Based on the results of life-cycle analysis, the economic properties and environmental impact of the two types of beam are investigated. In this paper, the effect of beam span on the design values, costs and carbon dioxide emissions is analyzed when investigating aspects of the structural design, economy and environmental impact. Different cross-sections are chosen for this purpose.

    Findings – The study shows that the glued laminated (abbreviated as glulam”) beams have a smaller tendency to lateral torsional buckling than the steel beams, and that they can be cheaper. From an environmental point of view, glulam beams are the more environmentally friendly option of the two beam materials. Furthermore, glulam beams may have a direct positive effect on the environment, considering the carbon-storage capacity of the wood. The disadvantage of glued wood is that larger dimensions are sometimes required.

    Research limitations/implications – Wind load and the effect of second-order effects have not been considered when analysing the static design. Only straight beams have been studied. Furthermore, the dynamic design of the beams has not been investigated, and the bearing pressure capacity of the supports has not been analyzed. We have investigated timber beams with a rectangular cross-section, and steel beams of rolled I-sections, known as “HEA profiles”. The cost analysis is based mainly on the manufacturing and assembly costs prevalent on the Swedish market. The only environmental impact investigated has been the emission of greenhouse gases. The design calculations are based on the European standards Eurocode 5 and Eurocode 3.

    Practical implications – To achieve sustainability in construction engineering, it is important to study the environmental and economic consequences of the building elements. By combining these two effects with the technical design of buildings made of steel and/or timber, the concept of sustainable development can be achieved in the long run.

     Social implications – The study concerns sustainability of building structures, which is an important of the sustainable development of the society.

     Originality/value – The paper contains new information, and will be useful to researchers and civil engineers.

  • 29.
    Hassan, Osama
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Schedin, Staffan
    Umeå universitet.
    Lundgren, Nils
    Umeå universitet.
    Girhammar, U.A
    Lulleå tekniska universitet.
    Experimental verification of static buckling of partially composite beams and beam-columns2015In: Proceeding Advanced Materials World Congress, 2015, Vol. 1Conference paper (Refereed)
    Abstract [en]

    The authors present an experimental study on static buckling of partially composite beams and beam-columns. In this context, a composite wall segment is tested consisting of timber studs connected to specially designed plywood board by means of shear connectors. The critical loads that characterise the buckling of timbre beams/columns with partial composite action are calculated both experimentally and theoretically. A good agreement is obtained between the analytical and experimental results. Further, it is discussed from the practical point of view that factors, which affect the deviation between the theoretical and experimental results. 

  • 30.
    Hellman, Pär
    Linköping University, Department of Science and Technology.
    Byggprojektstyrning med hjälp av dator -Studie utförd vid byggföretaget NCC2002Independent thesis Basic level (professional degree)Student thesis
    Abstract [sv]

    Styr is a computer program that the construction company NCC use in their construction projects. The program is used to keep the economy of their projects in a good order and things for the best in an early phase.

    The problem is a low extent of utilization. During the latest decade NCC has put a lot of job and money trying to develop the program. The question is how to get the employees to use the program in a greater extent.

    The aim of this graduationwork is to examine how to make the employees to utilize Styr better than they do today. My work contains specification from inquiry made by NCC and an inquiry made by my self. My inquiry was sent to productions employees. My work also contains a study literature about arrangement of projects and interviews with persons who are responsible for the program.

    The study has shown that the low extent of utilization do not depends on the single user but the whole company, from managing director down to production manager.

  • 31.
    Holmgren, Anna
    Linköping University, Department of Science and Technology.
    Brandskydd av stålprofiler2002Independent thesis Basic level (professional degree)Student thesis
    Abstract [en]

    This report is the result of a study on costs for fire protection of steel sections.

    The report starts with a description of the problem to find the most economic way to protect a steel column in a construktion with a specified fire classification. After this follows a general part about fire protection and then a comprehensive account of valid laws and regulations of importence for the dimensioning of the fire protect. Loads and other conditions that underlies the choice of column dimensions is described and chosen dimensions are shown in a table. Then follows a description of the materials for fire protection which is concidered: cladding with plaster-, fibre silicate-, and stone wool XXX and XXXpaint. The result includes a compilation table. To the report comes a number of appendix with specific material tables and results from the computer calculations.

  • 32.
    Holsten, Linda
    et al.
    Linköping University, Department of Science and Technology.
    Tolff, Lina
    Linköping University, Department of Science and Technology.
    Ombyggnation av nedlagd affärslokal till familjebostad2004Independent thesis Basic level (professional degree)Student thesis
    Abstract [sv]

    I samhället Hults Bruk ligger en nedlagd brukshandel, från 1951, som idag fungerar som samlingslokal för de boende i området. Holmen Skog, som äger alla fastigheter i området, planerar nu för en ombyggnation av den gamla brukshandeln till familjebostad.

    Vår uppgift var att utforma ett planlösninsförslag anpassat till en tvåbarnsfamilj för den aktuella byggnaden. Utöver detta skulle vi även upprätta rumsbeskrivning och köksuppställning samt ge förslag på ledningsdragningar, tomtutformning och källarplanlösning.

    Holmen hade vissa krav och önskemål för ombyggnationen. Dessa innebar huvudsakligen att eftersträva en rimlig kostdandsnivå och att hålla ner arbetsinsatserna genom att bevara många av de befintliga väggarna. Dessutom var det viktigt att inte göra för stora ingrepp i byggnadens fasad eftersom Holmen vill bevara det ursprungliga utseendet. Vi har även följt krav och anvisningar i BBR, SBN1980 och BÄR.

    Vi har vid framtagandet av denna rapport tillämpat lärdom och litteratur från kurserna Byggnads och samhällsplanering och Installationsteknik. Vi har haft kontinuerlig konsultation med vår handledare på Byggrosen som har hjälpt oss med diverse byggnadstekniska frågor. Samtliga ritningar har upprättats med hjälp av AutoCad.

    Vårt slutgiltiga förslag omfattar en bostad om fem rum och kök. Vi har prioriterat en öppen planlösning för att erhålla stora fri ytor och stora gemensamma ytrymmen. Många nya väggar måste resas då flera rum ska byggas. Dessutom behövs det sättas in nya fönster i de nya rummen. Vi har planerat för nya rördragningar och installationer då dessa är i originalmodell och behöver bytas ut. Nya vattenledningar samt ett nytt ventilationssystem bör installeras. Bostadens tillhörande tomt, som utgör en yta på ca 250 kvm, har vi utformat med bland annat en stenbelagd uteplats och nya planteringsytor. Resultatet av vår bostadsutformning innebär rimliga kostnader och arbetsinsatser samt att vi i stor utsträckning har lyckats bevara byggnadens yttre utseende.

  • 33.
    Håkansson, Patrik
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Kreivi, Johan
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Managing and calculating U-values with Dynamo and Excel2018Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    I de fallen där det är möjligt använder gärna byggnadsingenjören sig av standardlösningar med materialval och dimensioner som garanterar specifika U-värden. Standardlösningarna måste dock ibland frångås, vid exempelvis specifika krav på tjocklekar eller material som inte finns som standardlösning hos leverantörerna. Byggnadsingenjörens uppgift blir då tidskrävande gällande beräkningar av U-värden, där många iterativa beräkningar krävs, och att överföra konstruktionen till en 3D-modell. En rationalisering av detta arbetsflöde kan åstadkommas med hjälp av programmering. I denna studie skapas ett datorprogram i Visual Basic för Excel, som gör U-värdeberäkningar på olika väggkonstruktioner med trästomme. Även ett script i insticksprogrammet Dynamo skapas för att överföra den beräknade väggkonstruktionen till BIM-programmet Revit. Resultatet blev ett program som beräknar U-värdet, som även innehåller kontroller som hindrar användaren att ange felaktigt indata. Beräkningen med detta program ger en definitiv effektivisering i tid gentemot handberäkningar. Dock kan det ta tid att skriva ett sådant program för ovana, men med tidigare kännedom om programmering kan detta avhjälpas. Att ta sig an och lära sig Dynamo, hur det fungerar och var man hittar rätt funktioner var detta arbetes främsta svårighet. Dynamo bjuder på branta inlärningströsklar och ingen tidigare forskning som berörde det som gjordes i detta arbete. Ett fungerande script lyckades tillslut skapas, men mycket av det svåra arbetet skulle ha underlättats om tidigare kännedom om programmering funnits. Det kan således vara fördelaktigt för byggnadsingenjören som vill arbeta med Dynamo att lära sig programmering i deras utbildning.

  • 34.
    Hörlin, Jesper
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Jensen, Martin
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    The effect of building energy saving apartment blocks2014Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Att bygga energieffektiva bostäder blir idag allt viktigare. Grunden till detta arbete ligger i vårt intresse för energismart byggande och företagens nyfikenhet över huruvida de lyckats bygga energismart. Syftet med denna undersökning är att jämföra energiförbrukning för två principiella tillvägagångssätt att bygga flerbostadshus, som passiv- eller lågenergihus. De frågor som valts att behandla är:  Vad krävs för att ett hus ska klassas som ett passivhus respektive lågenergihus år 2009?  Klarar respektive konstruktion målet för energiförbrukning?  Vilka faktorer påverkar skillnaden i den specifika energiförbrukningen?  Vilken typ av koncept rekommenderas? Utifrån en teoretisk referensram inom området och tillhandahållet material, såsom ritningar och uppgifter om energiförbrukning, har en jämförelse mellan dessa två olika konstruktioner gjorts. Studien har riktat in sig på att studera parametrar som specifik energiförbrukning per Atemp och bidragande faktorer till en mer eller mindre lyckad energiförbrukning.

  • 35.
    Isaksson, Karl
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Petrén, Lars
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    LEED - Hur har projekt Gruset 1 påverkats av en miljöcertifiering enligt LEED, "New Construction and Major Renovations"2013Independent thesis Basic level (university diploma), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Before the end of 2011 the first warehouse that is certified under LEED was completed. LEED stands for Leadership in Energy and Environmental Design and is a environmental certification that was first launched the year of 2000. LEED is available in four levels - certified, silver, gold and platinum. What level the project will be certified with is based on a point-system that assesses the building in seven categories. This case study was certified with the level of gold. LEED is growing steadily and is now a well-established international environmental certification. At the time of writing (2012-03-27) more than 560 million m2 of commercial (which primarily serves the interests of profit) facilities are certified under LEED and are distributed over more than 31450 projects. This bachelor thesis is done on the behalf of Skanska Region Hus Sydost and includes how a LEED-certification affects the planning and production, how much additional cost the certification has brought to this project and how it affects the buildings value (measures that increase the property's market value) and how the certification is used by involved parties.

    For this case study it has been estimated that the LEED-certification has resulted in an additional cost of 2.11 %. To achieve the goal of the thesis mentioned in the paragraph above, there have been interviews with the following respondents: developer / clients, contractors, consultants and tenants. LEED is based on respondents' answers appeared to be a good alternative even if it meant some problems during the project.

  • 36.
    Jacobson, Linnea
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Karlsson, Viktor
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Design Model for Driven Concrete Piles According to Eurocode2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Pålning är en vanlig grundläggningsmetod för att överföra laster från överliggande konstruktioner genom svaga eller instabila jordlager till fasta jordlager eller berg. En typ av påle som ofta används är den slagna spetsburna betongpålen som slås ned genom till exempel lös lera till fast berg. 2011 trädde Eurokod in som gällande regelverk för dimensionering av bärverk. Införandet innebar förändringar i dimensionering av bland annat slagna spetsburna betongpålar. Företaget WSP i Norrköping har tidigare använt ett beräkningshjälpmedel för att få en uppfattning om en spetsburen betongpåles bärförmåga. Detta beräkningshjälpmedel blev i och med införandet av Eurokod inte längre giltigt. En önskan från WSP var att klargöra vad som gäller för dimensionering av spetsburna betongpålar enligt Eurokod och att ett nytt beräkningshjälpmedel skulle skapas om så var möjligt. När litteraturstudien för examensarbetet utfördes stod det klart att inget samlat dokument som beskrev alla delar av dimensionering av slagna spetsburna betongpålar fanns. Syftet med examensarbetet blev i och med det att sammanställa och tydliggöra gällande regelverk kring dimensionering av slagna spetsburna betongpålar. I den teoretiska referensramen sammanställs gällande regler och tillvägagångssätt för att utföra dimensioneringsberäkningar för en slagen spetsburen betongpåle. Det som sammanställts kan ses som ett förslag på hur dimensionering av en slagen spetsburen betongpåle kan genomföras. Resultatet visar att det är möjligt att skapa ett tillförlitligt beräkningsprogram som kan beräkna bärförmågan hos en spetsburen betongpåle enligt Eurokod. Vid jämförelsen av bärförmågan beräknad med det tidigare beräkningshjälpmedlet och det nya visade det sig att det nya ger en högre bärförmåga och framförallt ett noggrannare beräknat resultat.

  • 37.
    Jaredson, Sofia
    Linköping University, Department of Science and Technology.
    Utvärdering av Skvallertorget i Norrköping2002Independent thesis Basic level (professional degree)Student thesis
    Abstract [en]

    This thesis is an evaluation of the new traffic solution at “Skvallertorget”. The innovative theory behind it is to increase traffic-safety by introducing insecurity feelings for road-users.

    The conclusion of the evaluation is that the newtraffic solution is well adjusted according to guidelines for municipal traffic planning. The evaluation also illustrates the conflict between traffic planners deliberate attempt to avoid clear information and the road users wish to get it. The paradoxical situation is that the forced insecurity feelings on the road users seems to be required to increase the attention and thus the traffic safety.

  • 38.
    Johansson, Alexandra
    Linköping University, Department of Science and Technology.
    Från idé till verklighet - En klubblokal2010Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Enköping’s Rugby Club has long lacked a bigger hall to gather their members in, where they can meet and socializes outside trainings and games. Thanks to Enköping’s municipality, The Swedish Inheritance Fund, Swedish Sports Confederation, sponsors and club members the clubhouse will be built out with additional 100 square meters.

    The project is planned in two phases of which phase one is the buildup of the new clubhouse and phase two is the renovation of the existing part. Phase one started with the first groundbreaking in December 2006 and was finished for the season 2007. After the season 2007 phase two begun and was planned to be finished before the season 2008.

    The municipality was responsible for the groundwork and bas plate during phase one while AME Bygg AB was responsible for the building from the joist to the roof. Then Enköping’s RugbyClub took over and completed the building from the insulation to the interior design. Club members and sponsors provided their time and knowledge in form of carpenters, electricians, plumber, painters and various hobby-carpenters.

    To plan and push through this project has not been easy with many different individuals involved. One important part has been to elect one person or group to be responsible for layout and design. They also need to have the confident from the club and its members. Another important part to succeed in this project was the members and sponsors time and knowledge. Without them it would have been hard to succeed and minimize the cost.

    I and ERK are very proud and happy over our new clubhouse.

    Welcome to Enköpings Rugby Clubs new clubhouse

     

  • 39.
    Johansson, Jonas
    Linköping University, Department of Science and Technology.
    Energihushållning i byggnader: Historik och utveckling2009Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Tekniken inom energihushållning har utvecklats mycket de senaste 50 åren. Idag har vi en helt annan syn på uppvärmning och hushållning av energi i byggnader än vi hade då. Denna rapport kommer att fokusera på ventilation- och värmesystem eftersom dessa, tillsammans med isolering, har visat sig vara de viktigaste ur energihushållningssynpunkt.

    Det var egentligen efter oljekrisen i mitten på 70-talet som energihushållningsfrågan drog igång på allvar. Eftersom oljan blev dyrare så var man tvungen att hitta andra lösningar för att värma upp byggnader.

    Inomhusklimatet i bostäder, kontor, skolor och andra lokaler har en avgörande betydelse för människors hälsa och välbefinnande. Ändå har hälso- och komfortproblem med anknytning till inomhusklimatet varit ett stort problem. Problemen är främst dålig luftkvalitet, felaktiga eller låga luftflöden, drag (komfortproblem) samt för höga CO2 halter. Detta har ofta kopplats samman med energihushållningen. Anledningen till att det varit dåligt inomhusklimat är framför allt på grund av dåliga eller felaktiga ventilationslösningar.

    Idag har vi en lite annorlunda syn på uppvärmning av byggnader jämfört med för 50 år sedan. Det är inte bara viktigt för människors hälsa att bygga bra hus utan också för miljön. Byggnader står för en stor del av alla växthusgaser som släpps ut i atmosfären.

    Idag tror man att utvecklingen är påväg mot så kallade lågenergihus. Det är alltså byggnader som kräver förhållandevis lite energi till uppvärmning. Ett exempel på ett lågenergihus är passivhuset som blir mer och mer populärt. Inom EU diskuterar man i dagsläget en ny byggnorm som man vill införa 2016. Den innebär nybyggnation med passivhusstandard.

     

  • 40.
    Johansson, Robin
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Kartläggning av byggprocessen hos Peab med hjälp av SCOR2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Detta är ett examensarbete utfört på Institutionen för teknik och naturvetenskap (ITN) i Norrköping som är en del av Linköpings Universitet i samarbete med Peab som intressent.

    Historiskt sett har byggbranschens intresse för logistik varit svalt vilket har lett till att logistiken inom denna bransch har halkat efter i förhållande till övriga branscher. Syftet med detta examensarbete är att utifrån ett logistiskt synsätt tillhandahålla anpassningsförslag till SCOR-processerna ”Make” och ”Return” så att dessa stämmer bättre överens med byggbranschen i allmänhet samt finna förbättringsförslag kopplade till byggprocessen och returflöden av material hos Peab utifrån ett logistiskt hänsynstagande.

    För att kunna göra detta kommer examensarbetet avhandla hur byggbranschen passar in i SCOR-modellen i dagsläget med avseende på Make och Return. Därefter kommer exjobbet att komma med olika anpassningsförslag som framkommit längs med arbetets gång. Ett sådant förslag är att införa en nivå 4 i SCOR för Produce and Test (sM3.4) som ska gå in lite djupare i detalj på hur de olika byggnationsmomenten går till och vad som ingår i dessa. Ett annat förslag är att införa en ny nivå 3 process i SCOR som heter Inspection (sM3.5) som ska stå för den roll som slutbesiktningen har på en byggnation av detta slaget. Samtidigt som ovanstående förslag framkommer så finns det även vissa delar i SCOR som inte alls hör hemma i byggbranschen och därför bör tas bort helt.

    En av de saker som arbetet avhandlar är mätetal och nyttan i att använda mätetal. I samband med att förändringar av SCOR-modellen har presenterats har även ett urval av viktiga mätetal som finns representerade i SCOR tagits fram. Till dessa har sedan ytterligare några mätetal skapats som är unika för byggbranschen.

    Ett sätt för Peab att kunna utveckla sig och dra nytta av examensarbetet är att införa de förbättringsförslag som ges i form av att använda sig av de mätetal som är listade i examensarbetet, att faktiskt utnyttja de leveranstidplaner och ankomstregistreringsblanketter som tagits fram av Peab tidigare. Att följa upp och korrigera ritningar tidigare och se till att liknande handlingar finns på plats när byggnationen börjar. Att använda sig av standardiseringar för att underlätta tillgång och förbättra prissituationen och att slutligen även utvärdera de underentreprenörer och installatörer som de nyttjar sig av under en byggnation.

  • 41.
    Jonsson, Henric
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Production Strategy in Project Based Production within a House-Building Context2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A production strategy enables companies to effectively manage the different challenges that the production function face in a competitive environment. A production strategy helps a company to make operational and strategic decisions that follow a logical pattern and supports the corporate strategy and the competitive priorities of the company. When no strategy exists the decisions may be arbitrary and unpredictable leading to an under-achieving production system. Production strategy involves decisions that shape the long term capabilities of a producing company. For the traditional production industry there are a number of production strategy frameworks that facilitates the process of designing production systems. However, these frameworks typically leave project based production out of the scope or treat project based production as one type of production system, when in fact project based production systems can be multifaceted depending on product design and market requirements.

    This thesis focus on project based manufacturing in a house-building context. Houses can be produced by different types of production systems, and depending on how the production systems are designed they have strengths and weaknesses in different areas of competition. To be able to meet the increasing demand for residential houses, and improve performance in the house-building industry, the way houses are produced have to match different market requirements in a more effective and efficient way. To do this a production strategy has to exist. Typically there is a trade-off between productivity and flexibility, hence a production system designed to meet customer requirements concerning product design is probably not the best process choice if the customer thinks price and delivery time are the most important. A production strategy helps a company to make decisions so that the output of the production system meets customer requirements in the best possible way. Due to the fact that project based production is typically left out of the scope in traditional production strategy literature and that there is a lack of research concerning production strategy in a house-building context, the purpose of this research is:

    … to extend the production strategy body of knowledge concerning project based production in a house-building context.

    To fulfil the purpose the following four research questions are studied and answered:

    RQ1: What aspects can be useful in a classification matrix contrasting different production systems for house-building?

    RQ2: Which competitive priorities are important to measure when evaluating different production systems on a production strategy level in a house-building context, and how can they quantitatively be measured?

    RQ3: How does the characteristics of the production system, i.e. the process choice, affect information exchange in a house-building context?

    RQ4: How can a new production strategy be formulated and implemented in an industrialised house-building context and what challenges are important to consider in that process?

    To answer RQ1 a classification matrix was developed that classify production systems along two dimensions: a product dimension (degree of product standardisation) and a process dimension (degree of off-site assembly). The two dimensions are related, for example a high degree of standardisation should be matched with a high degree of off-site assembly and consequently a low degree of product standardisation should be matched with a low degree of off-suite assembly. A mismatch, e.g. high degree of off-site assembly and low degree of standardisation, typically leads to poor performance and should hence be avoided.

    To be able to see how different types of production systems perform in different areas of competition key performance indicators (KPIs) were developed. The KPIs presented in this research can be used to measure quality, delivery (speed and dependability), cost (level and dependability), and flexibility (volume and mix) at a production strategic level (RQ2).

    Furthermore, to answer RQ3, a production strategy perspective was taken on information exchange by relating information exchange to the design of the production system. The results indicate that employing different types of production systems leads to different approaches to information exchange. Employing a production systems using traditional production methods on-site and a low degree of product standardisation lead to a traditional approach to information exchange, e.g. project meetings, telephone and mail. Production systems employing some degree of off-site assembly have less complex and more stable supply chains and use ICT-solutions to a higher extent, which facilitates information exchange. The findings also indicate that a high degree of product standardisation facilitates the use of ICT-solutions such as ERP and BIM.

    RQ4 concerns the production strategy process, i.e. formulation and implementation. Failure in this processes can jeopardise the whole business. Based on a longitudinal case study of an industrialised house-builder a suggested production strategy process was developed, including both production strategy formulation and implementation. The study also identified context specific challenges that have to be considered in an industrialised house-building context, e.g. the complexity that comes with using two different production processes (off-site and on-site) in the same production system.

    The research is case based and a total number of eight different production systems have been studied. Data has been collected through interviews, observations, and review of company documents.

    List of papers
    1. Classification of production systems for industrialized building: a production strategy perspective
    Open this publication in new window or tab >>Classification of production systems for industrialized building: a production strategy perspective
    2013 (English)In: Construction Management and Economics, ISSN 0144-6193, E-ISSN 1466-433X, Vol. 32, no 1-2, p. 53-69Article in journal (Refereed) Published
    Abstract [en]

    The purpose is to develop a matrix for classifying production systems for construction with various degrees of industrialization. Previous attempts to classify industrialized production systems for construction focus on dimensions such as the design process, the product technology, or the supply chain structure, but none of them acknowledge the importance of how orders are actually won in the market and that different market segments have different requirements. Using production strategy theory as a base, a matrix is developed linking market requirements, via the product offering, to the design of the production system. The matrix positions typical production systems based on their respective degrees of product standardization and volumes relative to the degree of offsite production. Similar to production systems in manufacturing, production systems for construction also deliver manufacturing outputs at different levels, indicating that the choice of production system will affect the competitiveness of the company. The applicability of the matrix is exemplified through three case illustrations of concepts for industrialized building, and these show that the matrix can be used to analyse the production systems’ relative strengths and weaknesses. The matrix can also be used as a guide when developing new, or adjusting existing, production systems for industrialized building so that they will match market requirements and offer competitiveness.

    Place, publisher, year, edition, pages
    Routledge, 2013
    Keywords
    Construction industry, Industrialized housing, Off-site production, Operational research, Production process
    National Category
    Business Administration Construction Management Building Technologies Production Engineering, Human Work Science and Ergonomics
    Identifiers
    urn:nbn:se:liu:diva-96756 (URN)10.1080/01446193.2013.812226 (DOI)
    Available from: 2013-08-26 Created: 2013-08-26 Last updated: 2017-12-13
    2. A Production System Classification Matrix: Matching Product Standardization and Production System Design
    Open this publication in new window or tab >>A Production System Classification Matrix: Matching Product Standardization and Production System Design
    2015 (English)In: Journal of construction engineering and management, ISSN 0733-9364, E-ISSN 1943-7862, Vol. 141, no 6, article id 05015004Article in journal (Refereed) Published
    Abstract [en]

    The potential benefits of using off-site production in residential construction have been highlighted in many studies, but the full potential of off-site production approaches is not always realized. This shortfall can be explained by the mismatch between market requirements and the output offered by the production system, in other words, a mismatch between the degree of product standardization and the design of the production system. This mismatch could be resolved through a classification matrix that aids decision makers in matching market requirements and the degree of product standardization with the degree of off-site production and production system design. This paper describes the development of a classification matrix that guides the decision-making process during the designing of new or re-designing of existing production systems in residential construction. An important aspect of the development was balancing the trade-off between productivity and flexibility so that products can be produced competitively. The merits of the classification matrix are exemplified by five case companies with different approaches to industrialization and off-site production.

    Place, publisher, year, edition, pages
    American Society of Civil Engineers (ASCE), 2015
    Keywords
    Production strategy, Construction industry, Off-site production, Residential building, Process choice, Case study
    National Category
    Business Administration Construction Management Building Technologies Production Engineering, Human Work Science and Ergonomics
    Identifiers
    urn:nbn:se:liu:diva-105990 (URN)10.1061/(ASCE)CO.1943-7862.0000965 (DOI)000354550100004 ()
    Available from: 2014-04-16 Created: 2014-04-16 Last updated: 2017-12-13Bibliographically approved
    3. KPIs for measuring performance of production systems for residential building: A production strategy perspective
    Open this publication in new window or tab >>KPIs for measuring performance of production systems for residential building: A production strategy perspective
    2017 (English)In: Construction Innovation, ISSN 1471-4175, E-ISSN 1477-0857, Vol. 17, no 3, p. 381-403Article in journal (Refereed) Published
    Abstract [en]

    Purpose

    This paper aims to define key performance indicators (KPIs) for measuring performance of production systems for residential building from a production strategy perspective.

    Design/methodology/approach

    A literature review is done to identify suitable competitive priorities and to provide grounds for developing KPIs to measure them. The KPIs are evaluated and validated through interviews with industry experts from five case companies producing multifamily residences. Furthermore, two of the case companies are used to illustrate how the KPIs can be employed for analysing different production systems from a manufacturing strategy perspective.

    Findings

    Defined, and empirically validated, KPIs for measuring the competitive priorities quality, cost (level and dependability), delivery (speed and dependability) and flexibility (volume and mix) of different production systems.

    Research limitations/implications

    To further validate the KPIs, more empirical tests need to be done and further research also needs to address mix flexibility, which better needs to account for product range to provide a trustworthy KPI.

    Practical implications

    The defined KPIs can be used to evaluate and monitor the performance of different production systems’ ability to meet market demands, hence focusing on the link between the market and the firm’s production function. The KPIs can also be used to track a production systems’ ability to perform over time.

    Originality/value

    Most research that evaluate and compare production systems for residential building is based on qualitative estimations of manufacturing outputs. There is a lack of quantitative KPIs to measure performance at a strategic level. This research does this, identifying what to measure, but also how to measure four competitive priorities through 14 defined KPIs.

    Place, publisher, year, edition, pages
    Emerald Group Publishing Limited, 2017
    National Category
    Production Engineering, Human Work Science and Ergonomics
    Identifiers
    urn:nbn:se:liu:diva-143673 (URN)10.1108/CI-06-2016-0034 (DOI)
    Available from: 2017-12-13 Created: 2017-12-13 Last updated: 2018-01-05
  • 42.
    Jonsson, Henric
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Towards a Framework for Production Strategy in Construction2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The problem with low productivity increase in the construction industry is highlighted in many studies and in Sweden the need to improve productivity and client satisfaction in the construction industry has promoted a number of government investigations. One suggested way of improving productivity and client satisfaction is to move value adding activities offsite, to a more industrial environment. Compared to  traditional on-site production, off-site production has been said to have many advantages such as: higher productivity, lower production cost, higher quality and shorter lead times. The trade-off when increasing the degree of off-site production is the reduced product and process flexibility. The trade-off between productivity and flexibility indicates that different production systems perform well in different areas of competition.

    The purpose of this research is to develop a production strategy framework for the construction industry, and more specifically for the production of multifamily residences. This framework can help construction firms to design the production system and find the right balance between productivity and flexibility. For the manufacturing industry, production strategy frameworks have been developed and shown useful when designing new or redesigning existing production systems. A corresponding framework adapted to the construction industry would be useful for construction firms when designing production systems to meet the targeted market in the most efficient way.

    Production strategy theory is traditionally built around two broad groups, decision categories and competitive priorities. Decision categories are areas in which a company must make decisions that are of long term importance for the production function. In this thesis focus is on the decision category traditionally named product/process technology and more specifically on the so called process choice i.e. choosing a production system that meets the demands from the targeted market in the most efficient way. To do this a classification matrix is developed that classify production systems along two dimensions, the degree of off-site assembly in one dimension and the degree of product standardisation in the other. This way of visualising the process and product characteristic has been used before, in traditional production strategy frameworks, to facilitate the process choice.

    For the classification matrix to be useful, the positions in the suggested classification matrix must be linked to the ability of different production systems to deliver manufacturing outputs. Therefor a performance measurement system is developed. In the process of developing classification matrix and the performance measurement system three research questions are addressed:

    RQ1. What dimensions can be useful, from a production strategy perspective, when classifying different production systems for the production of multifamily residences?

    RQ2. What manufacturing outputs/competitive priorities have to be taken into consideration when evaluating different production systems forproduction of multifamily residences?

    RQ3. How should the ability of a production system to deliver manufacturing outputs be measured?

    To answer the research questions an abductive approach has been used. The results from a literature review have been used to develop theoretical constructs. Case studies have then been used to empirically test the constructs. Thereafter the empirical data and information from additional literature reviews has then been used to further develop and refine the theoretical constructs. The findings of this research are thereby grounded in both theory and practise.

    There are two main contributions in this thesis. The first one is the proposed classification matrix for production systems producing multifamily residences. The classification matrix can be used as a base for production strategy reasoning in the construction industry. The second contribution is the suggested performance measurement system in which KPIs for measuring quality, delivery (speed and dependability), cost (level and dependability) and flexibility (volume, mix and expansion) have been defined.

    By positioning different production systems in the classification matrix and then use the defined performance measurement system, relative differences between the ability of different production systems to deliver manufacturing outputs can be exposed. The classification matrix can help companies to work with production strategy in a structured way, and to visualize the link between the market strategy and the production function of the firm in order to meet the demands from the targeted market in the most efficient way.

    List of papers
    1. Classification of production systems for industrialized building: a production strategy perspective
    Open this publication in new window or tab >>Classification of production systems for industrialized building: a production strategy perspective
    2013 (English)In: Construction Management and Economics, ISSN 0144-6193, E-ISSN 1466-433X, Vol. 32, no 1-2, p. 53-69Article in journal (Refereed) Published
    Abstract [en]

    The purpose is to develop a matrix for classifying production systems for construction with various degrees of industrialization. Previous attempts to classify industrialized production systems for construction focus on dimensions such as the design process, the product technology, or the supply chain structure, but none of them acknowledge the importance of how orders are actually won in the market and that different market segments have different requirements. Using production strategy theory as a base, a matrix is developed linking market requirements, via the product offering, to the design of the production system. The matrix positions typical production systems based on their respective degrees of product standardization and volumes relative to the degree of offsite production. Similar to production systems in manufacturing, production systems for construction also deliver manufacturing outputs at different levels, indicating that the choice of production system will affect the competitiveness of the company. The applicability of the matrix is exemplified through three case illustrations of concepts for industrialized building, and these show that the matrix can be used to analyse the production systems’ relative strengths and weaknesses. The matrix can also be used as a guide when developing new, or adjusting existing, production systems for industrialized building so that they will match market requirements and offer competitiveness.

    Place, publisher, year, edition, pages
    Routledge, 2013
    Keywords
    Construction industry, Industrialized housing, Off-site production, Operational research, Production process
    National Category
    Business Administration Construction Management Building Technologies Production Engineering, Human Work Science and Ergonomics
    Identifiers
    urn:nbn:se:liu:diva-96756 (URN)10.1080/01446193.2013.812226 (DOI)
    Available from: 2013-08-26 Created: 2013-08-26 Last updated: 2017-12-13
    2. A Production System Classification Matrix: Matching Product Standardization and Production System Design
    Open this publication in new window or tab >>A Production System Classification Matrix: Matching Product Standardization and Production System Design
    2015 (English)In: Journal of construction engineering and management, ISSN 0733-9364, E-ISSN 1943-7862, Vol. 141, no 6, article id 05015004Article in journal (Refereed) Published
    Abstract [en]

    The potential benefits of using off-site production in residential construction have been highlighted in many studies, but the full potential of off-site production approaches is not always realized. This shortfall can be explained by the mismatch between market requirements and the output offered by the production system, in other words, a mismatch between the degree of product standardization and the design of the production system. This mismatch could be resolved through a classification matrix that aids decision makers in matching market requirements and the degree of product standardization with the degree of off-site production and production system design. This paper describes the development of a classification matrix that guides the decision-making process during the designing of new or re-designing of existing production systems in residential construction. An important aspect of the development was balancing the trade-off between productivity and flexibility so that products can be produced competitively. The merits of the classification matrix are exemplified by five case companies with different approaches to industrialization and off-site production.

    Place, publisher, year, edition, pages
    American Society of Civil Engineers (ASCE), 2015
    Keywords
    Production strategy, Construction industry, Off-site production, Residential building, Process choice, Case study
    National Category
    Business Administration Construction Management Building Technologies Production Engineering, Human Work Science and Ergonomics
    Identifiers
    urn:nbn:se:liu:diva-105990 (URN)10.1061/(ASCE)CO.1943-7862.0000965 (DOI)000354550100004 ()
    Available from: 2014-04-16 Created: 2014-04-16 Last updated: 2017-12-13Bibliographically approved
    3. Performance measurement for production systems in construction
    Open this publication in new window or tab >>Performance measurement for production systems in construction
    2014 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    This research focuses on performance measurement in construction and on defining quantitative metrics for typical manufacturing outputs (e.g. cost, delivery, quality and flexibility performance) within a production strategy framework. The metrics can be used to evaluate how different production systems perform in different areas of competition. A literature review is used to define both what manufacturing outputs that are relevant to measure and also how to measure those manufacturing outputs. The manufacturing outputs quality, cost (level and dependability), delivery (speed and dependability) and flexibility (volume, mix and expansion) are identified as important to measure when evaluating different production systems for production of multifamily residences, and key performance indicators (KPIs) are defined for each manufacturing output. The defined KPIs are derived from the literature review but also validated empirically through case studies. The main result of this research is a performance measurement system that can be used when evaluating different production systems in the construction industry.

    Keywords
    Production strategy, Performance measurement, KPI, Case study, Multifamily residences
    National Category
    Business Administration Construction Management Building Technologies Production Engineering, Human Work Science and Ergonomics
    Identifiers
    urn:nbn:se:liu:diva-105991 (URN)
    Available from: 2014-04-16 Created: 2014-04-16 Last updated: 2014-04-16Bibliographically approved
  • 43.
    Jonsson, Henric
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Rudberg, Martin
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    A Production System Classification Matrix: Matching Product Standardization and Production System Design2015In: Journal of construction engineering and management, ISSN 0733-9364, E-ISSN 1943-7862, Vol. 141, no 6, article id 05015004Article in journal (Refereed)
    Abstract [en]

    The potential benefits of using off-site production in residential construction have been highlighted in many studies, but the full potential of off-site production approaches is not always realized. This shortfall can be explained by the mismatch between market requirements and the output offered by the production system, in other words, a mismatch between the degree of product standardization and the design of the production system. This mismatch could be resolved through a classification matrix that aids decision makers in matching market requirements and the degree of product standardization with the degree of off-site production and production system design. This paper describes the development of a classification matrix that guides the decision-making process during the designing of new or re-designing of existing production systems in residential construction. An important aspect of the development was balancing the trade-off between productivity and flexibility so that products can be produced competitively. The merits of the classification matrix are exemplified by five case companies with different approaches to industrialization and off-site production.

  • 44.
    Jonsson, Henric
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Rudberg, Martin
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Classification of production systems for industrialized building: a production strategy perspective2013In: Construction Management and Economics, ISSN 0144-6193, E-ISSN 1466-433X, Vol. 32, no 1-2, p. 53-69Article in journal (Refereed)
    Abstract [en]

    The purpose is to develop a matrix for classifying production systems for construction with various degrees of industrialization. Previous attempts to classify industrialized production systems for construction focus on dimensions such as the design process, the product technology, or the supply chain structure, but none of them acknowledge the importance of how orders are actually won in the market and that different market segments have different requirements. Using production strategy theory as a base, a matrix is developed linking market requirements, via the product offering, to the design of the production system. The matrix positions typical production systems based on their respective degrees of product standardization and volumes relative to the degree of offsite production. Similar to production systems in manufacturing, production systems for construction also deliver manufacturing outputs at different levels, indicating that the choice of production system will affect the competitiveness of the company. The applicability of the matrix is exemplified through three case illustrations of concepts for industrialized building, and these show that the matrix can be used to analyse the production systems’ relative strengths and weaknesses. The matrix can also be used as a guide when developing new, or adjusting existing, production systems for industrialized building so that they will match market requirements and offer competitiveness.

  • 45.
    Jonsson, Henric
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Rudberg, Martin
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Classification of production systems in construction: A multiple case study2013In: Proceedings of the 20th EurOMA Conference: Operations Management at the Heart of the Recovery / [ed] Fynes, B. and Coughlan, P., 2013Conference paper (Refereed)
    Abstract [en]

    The purpose is to validate a conceptually developed classificationmatrix for production systems in construction through a multiple case study. Bymapping five different cases producing multifamily houses along the dimensions product standardisation and production volumes and degree of off-site assembly, and compare their relativestrengths and weaknesses, it is possible to determine how the position in thematrix affects their competitiveness. The case study indicates that theclassification matrix is a useful tool to characterize construction productionsystems. Differences in competitiveness are exposed, and this can be used whendeveloping an already existing, or designing a new, production system.

  • 46.
    Jonsson, Henric
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Rudberg, Martin
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Performance measurement for production systems in construction2014Manuscript (preprint) (Other academic)
    Abstract [en]

    This research focuses on performance measurement in construction and on defining quantitative metrics for typical manufacturing outputs (e.g. cost, delivery, quality and flexibility performance) within a production strategy framework. The metrics can be used to evaluate how different production systems perform in different areas of competition. A literature review is used to define both what manufacturing outputs that are relevant to measure and also how to measure those manufacturing outputs. The manufacturing outputs quality, cost (level and dependability), delivery (speed and dependability) and flexibility (volume, mix and expansion) are identified as important to measure when evaluating different production systems for production of multifamily residences, and key performance indicators (KPIs) are defined for each manufacturing output. The defined KPIs are derived from the literature review but also validated empirically through case studies. The main result of this research is a performance measurement system that can be used when evaluating different production systems in the construction industry.

  • 47.
    Joudi, Ali
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering. Energy and Environmental Technology, Dalarna University, Falun, Sweden.
    Cehlin, Mathias
    Building, Energy & Environmental Engineering, University of Gävle, Gävle, Sweden.
    Svedung, Harald
    SSAB Europe, Borlänge, Sweden.
    Rohdin, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Moshfegh, Bahram
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Influence of reflective interior surfaces on indoor thermal environment and energy use using a coupling model for energy simulation and CFD2015Manuscript (preprint) (Other academic)
    Abstract [en]

    The importance of reducing the building energy use and maintaining the desired indoor climate has long inspired creative solution such as optimized optical properties for building surfaces. This paper aims to address the influence of interior thermal reflective surfaces on both indoor thermal environments with high spatial resolution and energy use. To do so, this work employs a coupling method using building energy simulation (BES) and computational fluid dynamics (CFD). The results indicate increase in the mean radiation temperature (MRT) and reduction in the floor heating energy use by the use of interior reflective surfaces. The study yields analysis of operative temperatures and interior surface heat fluxes. Overall, the interior reflective surfaces can contribute to improved building thermal performance and energy saving.

  • 48.
    Joudi, Ali
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering. Energy Technology, Dalarna University, Falun, Sweden; SSAB Europe, Borlänge, Sweden.
    Cehlin, Mathias
    Building, Energy & Environmental Engineering, University of Gävle, Gävle, Sweden .
    Svedung, Harald
    Energy Technology, Dalarna University, Falun, Sweden; SSAB Europe, Borlänge, Sweden.
    Rönnelid, Mats
    Energy Technology, Dalarna University, Falun, Sweden .
    Moshfegh, Bahram
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering. Building, Energy & Environmental Engineering, University of Gävle, Gävle, Sweden .
    Numerical and experimental investigation of the influence of infrared reflective interior surfaces on building temperature distributions2017In: Indoor + Built Environment, ISSN 1420-326X, E-ISSN 1423-0070, Vol. 26, no 3, p. 355-367Article in journal (Refereed)
    Abstract [en]

    Radiative properties of interior surfaces can affect not only the building heat flux but also the indoor environment, the latter of which has not been thoroughly investigated. The aim of this study is to analyse the effect of surface emissivity on indoor air and surface temperature distributions in a test cabin with reflective interior surfaces. This was done by comparing experimental and simulation data of the test cabin with that of a normal cabin. This study employs transient computational fluid dynamics (CFD) using re-normalisation group (RNG) kε model, surface-to-surface radiation model and an enhanced wall function. Boundary conditions were assigned to exterior surfaces under variable outdoor conditions. The numerical and the measurement results indicate that using interior reflective surfaces will affect the indoor air temperature distribution by increasing the vertical temperature gradient depending on the time of the day. CFD simulations with high spatial resolution results show increased interior surface temperature gradients consistent with the increased vertical air temperature gradient. The influence of reflective surfaces is potentially greater with higher indoor surface temperature asymmetry. The vertical indoor air temperature gradient and surface temperatures are important parameters for indoor thermal comfort.

  • 49.
    Joudi, Ali
    et al.
    Energy and Environmental Technology, Dalarna University, Falun, Sweden.
    Svedung, Harald
    SSAB Europe, Borlänge, Sweden.
    Cehlin, Mathias
    Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik.
    Rönnelid, Mats
    Energy and Environmental Technology, Dalarna University, Falun, Sweden .
    Reflective coatings for interior and exterior of buildings and improving thermal performance2013In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 103, p. 562-570Article in journal (Refereed)
    Abstract [en]

    The importance of reducing building energy usage and thriving for more energy efficient architectures, has nurtured creative solutions and smart choices of materials in the last few decades. Among those are optimizing surface optical properties for both interior and exterior claddings of the building. Development in the coil-coating steel industries has now made it possible to allocate correct optical properties for steel clad buildings with improved thermal performance. Although the importance of the exterior coating and solar gain are thoroughly studied in many literatures, the effect of interior cladding are less tackled, especially when considering a combination of both interior and exterior reflective coatings. This paper contemplates the thermal behavior of small cabins with reflective coatings on both interior and exterior cladding, under different conditions and climates with the aim to clarify and point out to the potential energy saving by smart choices of clad coatings.

  • 50.
    Joudi, Mohammad Ali
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Radiation properties of coil-coated steel in building envelope surfaces and the influence on building thermal performance2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Recent studies have shown that the optical properties of building exterior surfaces are important in terms of energy use and thermal comfort. While the majority of the studies are related to exterior surfaces, the radiation properties of interior surfaces are less thoroughly investigated. Development in the coil-coating industries has now made it possible to allocate different optical properties for both exterior and interior surfaces of steel-clad buildings. The aim of this thesis is to investigate the influence of surface radiation properties with the focus on the thermal emittance of the interior surfaces, the modeling approaches and their consequences in the context of the building energy performance and indoor thermal environment.

    The study consists of both numerical and experimental investigations. The experimental investigations include parallel field measurements on three similar test cabins with different interior and exterior surface radiation properties in Borlänge, Sweden, and two ice rink arenas with normal and low emissive ceiling in Luleå, Sweden. The numerical methods include comparative simulations by the use of dynamic heat flux models, Building Energy Simulation (BES), Computational Fluid Dynamics (CFD) and a coupled model for BES and CFD. Several parametric studies and thermal performance analyses were carried out in combination with the different numerical methods.

    The parallel field measurements on the test cabins include the air, surface and radiation temperatures and energy use during passive and active (heating and cooling) measurements. Both measurement and comparative simulation results indicate an improvement in the indoor thermal environment when the interior surfaces have low emittance. In the ice rink arenas, surface and radiation temperature measurements indicate a considerable reduction in the ceiling-to-ice radiation by the use of low emittance surfaces, in agreement with a ceiling-toice radiation model using schematic dynamic heat flux calculations.

    The measurements in the test cabins indicate that the use of low emittance surfaces can increase the vertical indoor air temperature gradients depending on the time of day and outdoor conditions. This is in agreement with the transient CFD simulations having the boundary condition assigned on the exterior surfaces. The sensitivity analyses have been performed under different outdoor conditions and surface thermal radiation properties. The spatially resolved simulations indicate an increase in the air and surface temperature gradients by the use of low emittance coatings. This can allow for lower air temperature at the occupied zone during the summer.

    The combined effect of interior and exterior reflective coatings in terms of energy use has been investigated by the use of building energy simulation for different climates and internal heat loads. The results indicate possible energy savings by the smart choice of optical properties on interior and exterior surfaces of the building.

    Overall, it is concluded that the interior reflective coatings can contribute to building energy savings and improvement of the indoor thermal environment. This can be numerically investigated by the choice of appropriate models with respect to the level of detail and computational load. This thesis includes comparative simulations at different levels of detail.

    List of papers
    1. Highly reflective coatings for interior and exterior steel cladding and the energy efficiency of buildings
    Open this publication in new window or tab >>Highly reflective coatings for interior and exterior steel cladding and the energy efficiency of buildings
    2011 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 88, no 12, p. 4655-4666Article in journal (Refereed) Published
    Abstract [en]

    The effect of surface heat-radiation properties of coil-coated steel cladding material on the energy efficiency of buildings in Nordic climate is addressed by parallel temperature and energy usage measurements in a series of test cabins with different exterior solar reflectivity and interior thermal reflectivity. During one year, a number of one- or two-week experiments with air conditioner cooling and electrical floor heating were made while logging air-, radiation- and surface temperatures, energy consumption and weather conditions. Measurements show significant energy savings in the test cabins by the use of high thermal reflectivity interior surfaces both during heating and cooling and a strongly reduced cooling demand by the use of high solar reflectivity exterior surfaces. Results are interpreted within the context of a steady-state energy flux model, to illuminate the importance of surface resistance properties (radiation and convective heat dissipation).

    Place, publisher, year, edition, pages
    Elsevier, 2011
    Keywords
    Total solar reflectivity, Reflective coating, Thermal emissivity, Building interior heat flux, Energy efficient buildings Energy saving
    National Category
    Energy Systems
    Identifiers
    urn:nbn:se:liu:diva-118285 (URN)10.1016/j.apenergy.2011.06.002 (DOI)000295387200041 ()
    Available from: 2011-09-01 Created: 2015-05-25 Last updated: 2017-12-04Bibliographically approved
    2. Energy efficient surfaces on building sandwich panels - A dynamic simulation model
    Open this publication in new window or tab >>Energy efficient surfaces on building sandwich panels - A dynamic simulation model
    2011 (English)In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 43, no 9, p. 2462-2467Article in journal (Refereed) Published
    Abstract [en]

    The choice of building envelope is critical for the energy performance of buildings. The major part of the energy used by a building during its lifetime is used for maintaining a suitable interior thermal climate under varying exterior conditions. Although exterior heat radiation properties (i.e. total solar reflectivity and long wave thermal emissivity) have been well accepted to have a large impact on the need for active cooling in warmer climate, the effect of a reduced thermal emissivity on interior surfaces on the building thermal energy flux is rarely studied. This paper addresses the sensitivity of the thermal energy flux through a sandwich panel, by systematically varying the surface thermal emissivity (both interior and exterior) and total solar reflectance of exterior surface, for three geographical locations: southern, middle and northern Europe. A model is introduced for calculating the effect of both interior and exterior optical properties of a horizontal roof panel in terms of net energy flux per unit area. The results indicate potential energy saving by the smart choice of optical properties of interior and exterior surfaces.

    Keywords
    Total solar reflectivity, Reflective coating, Thermal emissivity, Building heat flux, Energy efficiency
    National Category
    Energy Systems
    Identifiers
    urn:nbn:se:liu:diva-118286 (URN)10.1016/j.enbuild.2011.05.026 (DOI)000294834900048 ()
    Available from: 2011-09-01 Created: 2015-05-25 Last updated: 2017-12-04Bibliographically approved
    3. Energy Efficient Buildings with Functional Steel Cladding
    Open this publication in new window or tab >>Energy Efficient Buildings with Functional Steel Cladding
    2011 (English)In: World Renewable Energy Congress, Linköping: Linköping University Electronic Press, 2011, Vol. 8, p. 2004-2009Conference paper, Published paper (Refereed)
    Abstract [en]

    The aim of the study is to develop a model for the energy balance of buildings that includes the effect from the radiation properties of interior and exterior surfaces of the building envelope. As a first step we have used ice arenas as case study objects to investigate the importance of interior low emissivity surfaces. Measurements have been done in two ice arenas in the north part of Sweden, one with lower and one with higher ceiling emissivity. The results show that the low emissivity ceiling gives a much lower radiation temperature interacting with the ice under similar conditions. The dynamic modelling of the roof in ice arenas shows a similar dependence of the roof-to-ice heat flux and the ceiling emissivity. A second part of the study focus on how to realise paints with very low thermal emissivity to be used on interior building surfaces.

    Place, publisher, year, edition, pages
    Linköping: Linköping University Electronic Press, 2011
    Series
    Linköping Electronic Conference Proceedings, ISSN 1650-3686, E-ISSN 1650-3740 ; 57
    Keywords
    energy balance, low emissivity, radiation properties
    National Category
    Energy Systems
    Identifiers
    urn:nbn:se:liu:diva-118287 (URN)10.3384/ecp110572004 (DOI)978-91-7393-070-3 (ISBN)
    Conference
    World Renewable Energy Congress – Sweden; 8–13 May, 2011, Linköping, Sweden
    Available from: 2015-05-25 Created: 2015-05-25 Last updated: 2018-01-29Bibliographically approved
    4. Reflective coatings for interior and exterior of buildings and improving thermal performance
    Open this publication in new window or tab >>Reflective coatings for interior and exterior of buildings and improving thermal performance
    2013 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 103, p. 562-570Article in journal (Refereed) Published
    Abstract [en]

    The importance of reducing building energy usage and thriving for more energy efficient architectures, has nurtured creative solutions and smart choices of materials in the last few decades. Among those are optimizing surface optical properties for both interior and exterior claddings of the building. Development in the coil-coating steel industries has now made it possible to allocate correct optical properties for steel clad buildings with improved thermal performance. Although the importance of the exterior coating and solar gain are thoroughly studied in many literatures, the effect of interior cladding are less tackled, especially when considering a combination of both interior and exterior reflective coatings. This paper contemplates the thermal behavior of small cabins with reflective coatings on both interior and exterior cladding, under different conditions and climates with the aim to clarify and point out to the potential energy saving by smart choices of clad coatings.

    Place, publisher, year, edition, pages
    Oxford: Elsevier, 2013
    Keywords
    Reflective coatings, Low energy building, Energy simulation, Total solar reflectance, Interior thermal emittance
    National Category
    Energy Systems Building Technologies
    Identifiers
    urn:nbn:se:liu:diva-118288 (URN)10.1016/j.apenergy.2012.10.019 (DOI)000314669500053 ()2-s2.0-84871715773 (Scopus ID)
    Available from: 2014-11-09 Created: 2015-05-25 Last updated: 2017-12-04Bibliographically approved
    5. Numerical and experimental investigation of the influence of infrared reflective interior surfaces on building temperature distributions
    Open this publication in new window or tab >>Numerical and experimental investigation of the influence of infrared reflective interior surfaces on building temperature distributions
    Show others...
    2017 (English)In: Indoor + Built Environment, ISSN 1420-326X, E-ISSN 1423-0070, Vol. 26, no 3, p. 355-367Article in journal (Refereed) Published
    Abstract [en]

    Radiative properties of interior surfaces can affect not only the building heat flux but also the indoor environment, the latter of which has not been thoroughly investigated. The aim of this study is to analyse the effect of surface emissivity on indoor air and surface temperature distributions in a test cabin with reflective interior surfaces. This was done by comparing experimental and simulation data of the test cabin with that of a normal cabin. This study employs transient computational fluid dynamics (CFD) using re-normalisation group (RNG) kε model, surface-to-surface radiation model and an enhanced wall function. Boundary conditions were assigned to exterior surfaces under variable outdoor conditions. The numerical and the measurement results indicate that using interior reflective surfaces will affect the indoor air temperature distribution by increasing the vertical temperature gradient depending on the time of the day. CFD simulations with high spatial resolution results show increased interior surface temperature gradients consistent with the increased vertical air temperature gradient. The influence of reflective surfaces is potentially greater with higher indoor surface temperature asymmetry. The vertical indoor air temperature gradient and surface temperatures are important parameters for indoor thermal comfort.

    Place, publisher, year, edition, pages
    Sage Publications, 2017
    Keywords
    Reflective interior surfaces, indoor air temperature gradient, Transient computational fluid dynamics, surface-to-surface radiation, building thermal performance
    National Category
    Energy Systems Building Technologies
    Identifiers
    urn:nbn:se:liu:diva-118289 (URN)10.1177/1420326X15609966 (DOI)000399487300007 ()
    Note

    Funding agencies|SSAB Europe; Dalarna University; University of Gävle; Linköping University.

    At the time for thesis presentation publication was in status: Manuscript

    Available from: 2015-05-25 Created: 2015-05-25 Last updated: 2017-05-05Bibliographically approved
    6. Influence of reflective interior surfaces on indoor thermal environment and energy use using a coupling model for energy simulation and CFD
    Open this publication in new window or tab >>Influence of reflective interior surfaces on indoor thermal environment and energy use using a coupling model for energy simulation and CFD
    Show others...
    2015 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    The importance of reducing the building energy use and maintaining the desired indoor climate has long inspired creative solution such as optimized optical properties for building surfaces. This paper aims to address the influence of interior thermal reflective surfaces on both indoor thermal environments with high spatial resolution and energy use. To do so, this work employs a coupling method using building energy simulation (BES) and computational fluid dynamics (CFD). The results indicate increase in the mean radiation temperature (MRT) and reduction in the floor heating energy use by the use of interior reflective surfaces. The study yields analysis of operative temperatures and interior surface heat fluxes. Overall, the interior reflective surfaces can contribute to improved building thermal performance and energy saving.

    Keywords
    Thermal reflective surfaces, mean radiation temperature, building thermal performance, coupling building energy simulation and CFD
    National Category
    Energy Systems Building Technologies
    Identifiers
    urn:nbn:se:liu:diva-118290 (URN)
    Available from: 2015-05-25 Created: 2015-05-25 Last updated: 2015-05-26Bibliographically approved
12 1 - 50 of 94
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  • rtf