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  • 251. Clarin, Mattias
    et al.
    Lagerqvist, Ove
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Residual stresses in square hollow sections made of high strength steel2005In: Advances in steel structures: proceedings of the fourth International Conference on Advances in Steel Structures / [ed] Z. Y. Shen, Amsterdam: Elsevier, 2005, p. 1577-1582Conference paper (Refereed)
  • 252.
    Clefjord Ljungberg, Hanna
    et al.
    Örebro University, School of Science and Technology.
    Brunzell, Malin
    Örebro University, School of Science and Technology.
    Analys av inköpsbeteende av underleverantörer2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 253. Cole, Raymond J.
    et al.
    Sterner, Eva
    Luleå tekniska universitet.
    Reconciling theory and practice of life-cycle costing2000In: Building Research & Information, ISSN 0961-3218, E-ISSN 1466-4321, Vol. 28, no 5-6, p. 368-375Article in journal (Refereed)
    Abstract [en]

    The notion of Life-Cycle Costing (LCC) is generally recognized as a valuable approach for comparing alternative building designs - enabling operational cost benefits to be evaluated against any initial cost increases. However, a host of practical difficulties conspire to limit its widespread adoption. This limited acceptance is particularly important in green building where many of the benefits of strategic choices can often only be understood and justified when cast in a life-cycle context. This paper identifies some of the critical gaps between the theory (and promise) and practice of Life-Cycle Cost analysis to discover strategies that encourage greater use.

  • 254.
    Collin, Olle
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Levin, Anna
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Att säkerställa vidhäftning mellan prefabricerade betongbjälklag och påhgjutning: Från konstruktör till byggarbetsplats2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 255.
    Crafoord, Madeleine
    et al.
    Jönköping University.
    Hedberg, Gabriella
    Jönköping University.
    Informationsflöde inom prefabprocessen: Hur kan Derome Träteknik effektivisera informationsflödet från konstruktion till produktion?2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The study aimed to investigate how the information flow at an off-site fabrication is working, from design-stage to production. More specifically, it focus on identifying effective and ineffective parts in the information flow, along with improvement opportunities to optimize the personnel’s daily work.

    Since the authors had no knowledge about where the problems in the information flow at the company was, they were not able to create a theoretical framework before the case study was made. The case study involved observation and interviews. The observation was made to identify the process and information flow at the company. The interviews were made to get the knowledge about the personnel’s opinion and to locate where the problems in the information flow occurred. With the case study as a base the theoretical framework could be made with a literature study.

    The problem areas that emerged from the case study are all mainly based from the lack of time. This is partly due to the time-consuming activities such as manual handling in the making of production technical drawing and revision of planning documents. The improvement proposal the authors present is to upgrade the computer-aided design software and to implement a planning system. The authors also consider the lack of time as a reason for shortcomings in the communication. The improvement proposal the authors present for this is to keep the personal contact and to supplement it with a system.

    The study intends to contribute with knowledge about how an information flow at an off-site fabrication may look like. It reinforces theories about why it is important to keep the personal communication when a system upgrade are implemented. The study has also contributed in proposals in which parts of the information flow that have potential to become more effective at an off-site fabrication.

    The study was limited to an off-site fabrication and only the information flow between design-stage and production was included in the study. No economic aspects were considered and only one company has participated in the study.

  • 256. Croon, Ingemar
    et al.
    Apleberger, Lennart
    Stehn, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Trämekaniska industrin måste lyfta sig i håret2002In: Svensk papperstidning, ISSN 1403-9605, no 12, p. 10-12Article in journal (Other (popular science, discussion, etc.))
  • 257.
    Dadhich, Siddharth
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Assisted Tele-Remote Control of Wheel Loaders in Underground Mining2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Tele-remote operation of mobile earth-moving machines in underground mines supported byoperator assistance functions is attractive for safety and productivity reasons. This way, operatorscan avoid hazardous underground environments with poor air quality and the productivitycan, in principle, be improved by saving the time required to commute drivers to and fromthe operational areas. The infrastructure needed to do tele-remote control in the form of highcapacitywireless IP networks is nowadays being deployed in underground mines. In mineswith sufficiently high ceilings, wheel loaders are used in short loading cycles to load blastedrock onto dump trucks. Bucket filling on remote control is less efficient than manual operationdue to the loss of sensory perception resulting from not being in the actual environment.Automatic bucket filling algorithms have been developed earlier but, due to the complexity ofbucket-environment interactions, such algorithms have not produced satisfactory results and arenot commercially available. If tele-remote operation is enabled, it can also be used to rescuefuture autonomous machines, when they malfunction. This thesis presents the key challengesin automation and tele-remote operation of earth-moving machines, surveys the literature andavailable technologies to address these challenges. The key contributions of this thesis are highlightingimportant knowledge gaps based on a survey in the field of automation of earth-movingmachines and proposing a machine learning based framework for automatic bucket filling forfront-end loaders. The proposed machine learning based approach to automatic bucket fillinguses linear regression and classification models of lift and tilt actions, which are fitted to thebehavior of an expert driver filling the bucket with gravel pile. The models of operator behaviorfrom the recorded data reveals relationships between sensor data and operator actionsand shows that a learning based approach is feasible. A case study has been done on the useof wheel-loaders in underground mining presenting the use case of assisted tele-remote controlbased on audio-video and sensor feedback. A good communication setup, that considers requirementsof real-time video transmission, is important for tele-remote control. Furthermore,a simulation study evaluates two transport layer protocols with respect to video quality for teleremotecontrol over wireless IEEE 802.11 networks. It has been identified that adding operatorassistance functions to tele-remote control is a good approach towards autonomous operation ofearth moving equipment.i

  • 258.
    Dagdony, Masara
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Rashid, Toba
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Kolfiberförstärkning av betongkonstruktioner med avseende på böjningoch tvärkraft: En hypotetiskt plattrambro modellerad i Brigade Standard och en T-balk2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The society changes constantly, but this does not only affect the inhabitants of the society, but also

    that new demands are made on the construction used by the people. Many constructions may therefore

    require reinforcement after a certain amount of time. The need for reinforcement may be due many

    different reasons for example to altered use, corrosion to internal reinforcement or may be due to

    design errors, accidents or new standards. It is more beneficial to reinforce the structure than to tear it

    down and replace it to meet current requirements.

    The purpose of this thesis is to investigate carbon fiber reinforced polymer, CFRP, as a method to

    strengthen concrete structures. The report presents calculations that were made to investigate the

    increase in bending and shear capacity after a performed reinforcement. Alongside the calculations,

    existing templates for this method were checked and developed.

    In order to achieve the purpose, two hypothetical concrete structures were investigated. One design is

    a frame bridge modeled in the FEM program Brigade Standard. Calculations on the frame bridge were

    made with respect to bending. The other construction that was investigated is a T-beam. On the Tbeam,

    shear capacity was examined before and after reinforced carbon fiber reinforcement.

    The result present the amount of carbon fiber required to achieve the desired capacity of the structures.

    The result also describes the capacity achieved after carbon fiber reinforcement.

  • 259.
    Daher, Bchar
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Aksar, Joachim
    Halmstad University, School of Business and Engineering (SET).
    Solavskärmning med solceller och dess inverkan på energianvändning och inneklimat2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 260.
    Dahir, Mohamed
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Invändig eller Utvändig tilläggsisolering av ett flerbostadshus- LCC analys av optimal isoleringstjocklekar: Fallstudie på Sicksackvägen 39 i Gävle2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Stadsdelen Sätra som ligger 3 km norr om Gävle centrum uppfördes undermiljonprogrammet mellan 1960-1974. Det är enkelt och ta sig till och från Sätramed både fordon, cykel och till fots. AB Gavlegårdarna har tagit initiativ till attrenovera deras byggnadsbestånd som uppfördes under miljonprogrammet istadsdelen Sätra, däribland Sicksackvägen 39. Byggnaden har byggts 1969 ifunktionalistisk stil i närheten av Sätra Centrum.Syftet med denna studie var att undersöka den kostnadsoptimala isoleringstjocklenvid invändig eller utvändig tilläggsisolering av husets ytterväggar. Med hänsyn tillandra åtgärder som AB Gavlegårdarna vill genomföra vid renovering av denbefintliga byggnaden.För att genomföra denna studie har en okulärbesiktning, litteraturstudie,beräkningar, uppmätningar, undersökningar, samt energisimulering utförts. Därpåjämfördes lönsamheten vid tilläggsisolering med optimala isoleringstjocklekeninvändigt respektive utvändigt.Resultatet av denna studie visar att de komponenter i husets klimatskärm somläcker mest värme är ytterväggar och fönster. Med hänsyn taget till derenoveringsåtgärder som AB Gavlegårdarna ska genomföra blir den optimalaisoleringstjockleken invändigt är 45 mm och utvändigt 170 mm. Den åtgärd som germest lönsamhet är tilläggsisolering utvändigt med 170 mm mineralull i kombinationmed AB Gavlegårdarnas renoveringsåtgärder: fönsterbyte och uppgradering avventilationssystemet till FTX.

  • 261.
    Dahl, Arvid
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Lindström, Charlie
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Mekanisk prestanda hos traditionella träfogar kontra samtida byggbeslag2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Societies demand for environmentally friendly and sustainable construction is ever increasing. One way to meet these new demands on environmentally friendly construction is to use more wood which decreases carbon emissions through the substitution effect. This report aims to research whether traditional joinery techniques entirely executed in wood can replace contemporary joinery techniques in future construction. The goal is to show whether this is possible from a strength standpoint. The research will be limited in that it will strictly seek to study a pillar-beamconnection where the traditional joint researched will be three varying mortise and tenon joints and the contemporary joint is a joist hanger. The joints will be analyzed with calculation and experimentation where the load case aims to produce mainly shear in the joint. The results point towards it being possible to introduce this traditional joint in contemporary construction.

  • 262.
    Dahlin, Alexander
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Hansson, Håkan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Fuktmätningsmetoder i VST System: En studie i fuktmätnings metodik gällande VST systems väggmoduler2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 263.
    Damberg Larsson, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    GNSS-baserat grävsystem i VA-projekt: En undersökning om GNSS-baserade grävsystem ger ökad produktivitet och säkerhet i medelstora VA-projekt2018Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The use of machine control has long been common in major road construction and railway construction. However, machine control has become more and more common when digging trenches for pipe laying, but there are not many studies on how the use of machine control affects a work as trench digging for pipe laying.

     

    The report will investigate how a sewer, water and drain pipe project is influenced by using excavators that are equipped with machine control. The investigation will be conducted in two parts and will cover three different themes, economics, work environment and environment.

     

    Different questionnaires were customized for people with different positions. The persons surveyed were workers affected by the use of machine control in projects. These surveys addressed all three of the above topics.

     

    In order to make a deeper study of how the use of machine control affects the economy, figures on costs and progress / productivity were collected from a trench digging and pipe laying project in Toverud, Hammarö. There they used excavators that were equipped with machine control. These figures were compared to a reference project that was also carried out in Hammarö, but in 2009 when machine control was not used.

     

    The result shows that the use of machine control increases productivity while reducing workload and dangers for workers. Because the same type of work is carried out in less time, the total fuel consumption for the project decreases. The calculations showed that a work involving 1100 meters of trench digging and pipe laying. There would be savings up to around 3178 liters of diesel, and that the execution time would be about 15 days faster if the excavators were equipped with machine control.

    A limitation of machine control is that there is a lot of work for the surveyor if many revisions of the drawings are required. It is very important that the surveyor performs well with the line profile, otherwise the positive effects of using machine control at work will disappear. High buildings and forests can be a problem for the reception.

    The conclusion is that productivity increases and quality in the work environment is improved when using machine control.

  • 264.
    Danielski, Itai
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Energy variations in apartment buildings due to different shape factors and relative size of common areas2011In: World Renewable Energy Congress 2011, Linköping, Sweden, May 8-11, 2011Conference paper (Refereed)
  • 265.
    Danielski, Itai
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Large variations in specific final energy use in Swedish apartment buildings: Causes and solutions2012In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 49, p. 276-285Article in journal (Refereed)
    Abstract [en]

    This study examines possible causes for variations in specific final energy use in new apartment buildings. The analysis is based on case studies of 22 new apartment buildings that were constructed as part of the ’Stockholm program for environmentally adapted buildings’. The buildings in the study were chosen because they share similar construction characteristics and similar energy systems but display unexpected large variations in specific energy use. Three causes were found to contribute to variations in monitored specific final energy use in the studied apartment buildings: (1) the time interval between the completion of construction work and the actual energy measurements, (2) the shape factor of the building and (3) the relative size of the common area. In addition, the buildings that participated in the Stockholm program failed to achieve the requirements for the specific final energy use, to a large extent, because of expectations based on the simulated values. The simulated specific final energy use predicted by the energy simulations were on average 19% lower than the monitored values, giving the impression that the buildings would fulfill the program’s energy requirements. The reasons for the low simulated values were determined to be large uncertainties in the input data. © 2012 Elsevier B.V. All rights reserved.

  • 266.
    Danielsson, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Produktionsuppföljning: För att underlätta styrning i projekt samt ge återkoppling i form av produktionsdata till kalkylator2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    För att lära sig och förbättras är det viktigt att ta till vara på erhållna erfarenheter. Det är även  viktigt att genom rätt beslut driva projekt på ett lönsamt sätt. Vid företaget i fallstudien upplever kalkylatorerna att erfarenhetsåterföringen och uppföljningsarbetet har brister. Bakgrunden till examensarbetet är att kalkylatorerna vill få bättre återkoppling på sina kalkyler. Syftet med examensarbetet är att undersöka hur uppföljningsarbetet fungerar och hur det kan förbättras vid företaget i fallstudien.

     

    Examensarbetet har genomförts vid Peab Anläggning AB, Region Nord i Luleå.

    Empirin har till största del utförts genom 10st kvalitativa intervjuer med personal vid företaget men även utifrån deltagande observation vid några av företagets projekt. En uppföljningsmall har även konstruerats och utvärderats i företagets projekt.

     

    Vid företaget i fallstudien är det ovanligt med återkoppling till kalkylatorn i form av nedskrivna produktionsdata. Det finns inget strukturerat sätt/hjälpmedel för att bedriva uppföljningsarbeten. Uppföljningar som görs vid företaget blir därför baserade på vad platschefen i projekten är intresserad av vilket resulterar i att nedskrivna produktionsdata sällan tas fram.

     

    Det finns förbättringspotential för produktionsuppföljning och erfarenhetsåterföring. I detta examensarbete ges förslag på uppföljningsmall som underlättar en enkel och snabb produktionsuppföljning i projekten. Genom mallen fås erfarenhetsvärden i form av produktionsdata som genom återkoppling till kalkylavdelningen ger ett underlag och stöd i kalkyleringsprocessen. Förutom erfarenhetsvärden ger denna uppföljningsmall ett styrningsunderlag för platschefen i projektet där uppföljningen görs.

     

    Det finns mycket kunskap och erfarenhet inom företaget och det finns mycket att vinna genom att ta vara på erfarenheter från genomförda projekt.

  • 267.
    Danielsson, Christoffer
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Hansson, Christopher
    Dalarna University, School of Technology and Business Studies, Construction.
    Planindikatorer som utvärderingsverktyg för hållbar fysisk planering: En konsekvensbedömning på detaljplanenivå2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The urbanization that has occurred in the last century results in an increasing awareness of urban planning and assessment tools are increasingly used to demonstrate that development in the direction of sustainable occurs.

    The purpose of this study is to produce indicators and analyze how the municipality development plans for the station area in Borlänge meet the national-, regional- and local objectives in terms of sustainable urban planning. The method applied in the development of indicators is based on Boverkets and Naturvårdsverkets model that was developed in conjunction with the SAMS-project. Applying this method has resulted in eleven indicators that have been applied to the present situation and the development plans in which the result shows that any major change to the assessment ladder has not occurred.

    As a result of some municipal goals beeing vaguely designed, the difficulty in meeting them increases. This creates a difficulty in applying the assessment tools in the form of indicators that can guide planning in the right direction. The development plans extent is not enough for the municipal goals to be met. The produced planning indicators can be the basis for a dialogue with the municipality in order to sharpen the objectives and generate a better goal achievement.

  • 268.
    Danielsson, Erik
    et al.
    Mälardalen University, Department of Public Technology. Mälardalen University, School of Sustainable Development of Society and Technology.
    Robertsson, Hans
    Mälardalen University, Department of Public Technology. Mälardalen University, School of Sustainable Development of Society and Technology.
    Examensarbete: Prefabricerad produktion med betongelement: En kostnadsutvärdering mellan prefabricerad och platsbyggd produktion2008Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 269.
    Daoud, Abraham
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Andric, Nikola
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Implementering av drönarteknik i byggprocessen2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

     

    The construction industry is undergoing a digitalization, where drone technology is part of the modernization of working methods. Drones are used by an increasing number of companies. Construction companies aim to make cost and time effective solutions while improving the working environment.

    The purpose of this report is to compare how implementation of drone technology affects economy, time and work environment during external inspection of buildings and volume calculations.

    In order to collect relevant information, the survey consisted of literature studies, interviews, questionnaires and case studies in which a drone as a tool has been tested in practice. The results of the survey have demonstrated the benefits of implementing drones as a work tool in terms of economy, time and work environment. Compared to traditional working methods, the results show that the drone is a cheaper and more flexible tool to use, as well as improving the working environment since the drone can be operated from ground level.

    Based on the results of the report, the conclusion has been that profits can be made by implementing drones at construction companies. The recommendation is that the purchase of drones should be regarded as a good investment for construction companies.

  • 270.
    Daoud, Kristina
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Marouf, Arkan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    SPÄNNVIDDER I STOMKONSTRUKTIONERAV LIMTRÄ OCH STÅL2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There are different methods of constructing frame systems. The choice of material has an influence on the final outcome of the frame system. This bachelor’s thesis includes a comparison on frame systems constructed in steel and glulam. Due to an assignment from Wästbygg AB an investigation has been made regarding which of the material is more suitable for an industrial building with an area of 15,000 m2. The building is to be constructed in Stockholm, and frame systems with a span of 45 meter will be compared to each other. The sizing and construction analysis for both frame systems in steel and glulam has been calculated according to Eurocode. Amount of construction parts needed to finish the build is compiled in a list, which is then used to make an appreciated cost summary for the construction. The cost of transportation to the site of the building is included in the cost. Results for the cost of the materials have been made with collaboration with the material suppliers. The cost summary shows that frame system in steel is economically better, with a lower cost of 1 650 000 kr less than glulam. Information about the different materials has been collected by litterateurs, web pages and interviews. The information is then compared to each other and a result by different characteristic qualities has been made. These qualities are then graded depended on how the materials match a sort of quality that is required in a frame system. Some qualities are more important than others, so there is a contention that some qualitys are better for frame system than others, for example if the material has solidity rather than being esthetic. Especially when constructing a large building as this. It is concluded that the choice of material depends on the type of building that is to be constructed.

  • 271.
    Davidov, Viktor
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Construction Engineering.
    iPad på en byggarbetsplats: Det effektiva och papperslösa sättet att arbeta på2011Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Quality assurance of construction projects and create effective ways of working, is intoday's pressed position, major objectives for building contractor companies. This thesis is an attempt to see if it is possible to achieve these goals with the new modern tool iPad.

    The author of this thesis has during the latter half of his one year practice work in Uppsala for the Swedish building construction company NCC Construction Sverige AB, conducted a study on the possibility of using the iPad on an construction site. This has been done with active field studies in which applications have been tested and also the supervisors receptive. The usability of the iPad has always been in focus since it is important that the applications are easy to use and easy to learn.

    The results of the work, as presented in this report, points at opportunities in efficiency if the iPad is introduced and used on construction site. There are many useful applications for the iPad, and with a system that can handle the synchronization between the iPad and the computer, the workflow will be streamlined significantly.

  • 272.
    Dehlin, S.
    et al.
    NCC Construction Sverige AB.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Racz, Tamas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Heikkilä, K.
    Colvo Group Real Estate.
    Practical application of a newly developed automated building energy-analysis software module prototype2012In: eWork and eBusiness in Architecture, Engineering and Construction: Proceedings of the European Conference on Product and Process Modelling 2012 , ECPPM 2012 / [ed] Gudni Gudnason; R J Scherer, Boca Raton: CRC Press, Taylor & Francis Group , 2012, p. 45-49Conference paper (Refereed)
    Abstract [en]

    One key challenge when it comes to developing industrial building concepts for the housing industry is improving the energy performance of buildings, while at the same time ensuring that the end product remains affordable and attractive to customers. This paper summarises the findings from the application of a newly developed prototype for an automated energy-analysis software module in a real-life project.The prototype is used for the energy analysis of the low-energy, multi-family residential P303 concept developed by NCC Construction Sverige AB - a leading construction and development company in the Nordic region. A building concept is based on continuity and repetitions of most of the building components. Most of its characteristics are known and defined beforehand and only a few parameters vary due to the adaptation of the concept, for example, the configuration or site location. In energy performance calculations, the proposed energy-analysis software module prototype processes the known parameters as constants and only varies the unknown parameters. The energy calculations are then carried out by the calculation kernel from the dynamic building simulation software module, VIP Energy, and the result is exported to an Excel spreadsheet where it is presented in a table. This makes it possible, in a practical manner, to execute a larger number of performance analyses in a shorter time, investigating different design alternatives and configurations and thereby facilitating optimisation towards the best possible design solution. The case study presented in this paper simulated energy losses through the building envelope of a real P303 building. The parameters that were varied are the location and orientation of the building and various energy characteristics of windows/glazing.

  • 273.
    Dehlin, Stefan
    et al.
    NCC.
    Heikkilä, Katarina
    NCC.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Schade, Jutta
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Racz, Tamas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    Eriksson, Per-Erik
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Effektive projektering av lågenergihus2011Report (Other academic)
    Abstract [sv]

    Byggbranschen står inför stora miljö- som affärsmässiga utmaningar med krav på att reducera energiförbrukning och miljöpåverkan. Detta projekt syftar till att bidra medkunskap hur energiprojektering kan effektiviseras vid nyproduktion avlågenergibyggnader där det övergripande målet är att stödja ett långsiktigt hållbart och lönsamt byggande. Studien har genomförts i samverkan mellan byggbransch och akademi genom fallstudier och enkätundersökningen.Resultatet visar på behovet och nyttan av att redan i tidigt planeringsskede utreda konsekvensen av olika alternativ av exempelvis byggnadsutformning ochklimatskärmens tekniska prestanda. Det spelar mindre roll vilket energiberäkningsverktyg man använder om resultatet används för att jämföra olika alternativ med varandra.Skillnaderna i krav och institutionella ramverk vad gäller energiprestanda påverkar också projektering av energieffektiva byggnader. En jämförande studie av hur man hanterar energifrågor från krav till färdig lösning mellan Tyskland och Sverige visar på ett behov av vidareutbildning i energifrågor för arkitekter och ingenjörer i Sverige som kommer in tidigt i byggprocessen. Undersökningen och jämförelsen pekar också mot ett behov av en sammanlänkande funktion, här kallad energisamordnare.Energisamordnarens roll är att föra in energikompetens in i projektet, säkerställa att krav och mål formuleras och hanteras samt aktivt delta i projekteringen för att guida utformningen av byggnaden mot en effektiv och låg energiförbrukning.Vi kan konstatera att det är marknadskrafter och engagemang från byggare, beställare och lokala myndigheter snarare än nationella krav som driverenergieffektivisering framåt i Sverige idag. Det kan emellertid leda till en situation där krav på energieffektivitet blir lokalt satta vilket kan leda till svårigheter för utvecklare av olika typer av byggnadssystem för bostäder och lokaler. Därför är det önskvärt att utvecklingen av byggnadstekniken som skett de senaste åren också följs upp av Boverket i form av krav som ligger i framkant snarare än minimikrav för att förhindra att en flora av lokala krav uppstår som kan verka som "handelshinder" för den fortsatta utvecklingen av det industriella byggandet i Sverige.Vi ser också ett tydligt behov för ökad samverkan och integration för att kunna driva energieffektiviseringen framåt men samtidigt också ett tydligt behov av att utveckla upphandlings- och samverkansformer för att möjliggöra detta. Upphandlingen, till exempel, bör utformas så att lämpliga aktörer väljs utifrån mjuka parametrar och involveras tidigt under projekteringsskedet samt ges ekonomiska incitamentkopplade till projektets mål, ekonomi och tidplan.Projektet har också undersökt hur man skall åstadkomma en mer integreradprojekteringsprocess genom att: Skapa en struktur för att samla, uttrycka och klargöra mål och krav ochutveckla dessa mot funktionskrav och tekniska lösningar. Genomföra en modellbaserad projektering som detaljerar tekniska lösningarallteftersom de utvecklas.Införa beslutsstöd för energifrågor i projektutveckling där produktensprestanda successivt jämförs mot funktionskrav med hjälp av alltmerdetaljerade prestandaanalyser.I projektet har också ett nyutvecklat formellt beslutsstöd exemplifierats där fleraalternativa lösningar kan utvärderas mot olika kriterier (MADM) vilka kanorganiseras och viktas hierarkiskt utifrån projektets mål och krav.I projektets har en prototyp, en så kallad energikonfigurator, utvecklats för atteffektivisera produkt och projektutveckling av s.k. konceptbyggande. Användandet har demonstrerats på NCC:s koncept P303 där man optimerat konfigureringen i produkt och projektutveckling efter både subjektiva och objektiva kriterier som tänkas efterlikna ett visst kundsegment. Hundratals alternativa utformningar kan utvärderas på några minuter i jämförelse med dagar och veckor om samma analyser skulle göras för hand med hjälp av energiberäkningsprogram med manuell inmatning av indata.För att effektivisera projekteringen mot ett energieffektivt byggande rekommenderar projektet att:Man tidigt upphandlar och involverar de viktigaste aktörerna så att man tidigtkan inkludera energiaspekter i utformning av koncept. Beställaren aktivt deltar i kravformuleringen och i analys- ochbeslutsprocessen. Dels för att säkerställa val mot uppställda krav och behovoch dels för att tillgodose de praktiska behov som uppstår i och med enintegrerad och modellbaserad projekteringsprocess. Utse en energisamordnare som skall säkerställa att formulerade energikravoch mål hanteras optimalt för att guida utformningen av byggnaden mot eneffektiv och låg energiförbrukning. Använda en modellbaserad projekteringsprocess för utformning, simuleringoch analys av konceptlösningar gentemot energirelaterade aspekter. Energianalyser som görs i tidigt skede används för att jämföra olikaalternativa utformningar. När detaljeringsnivån ökar bör man användadynamiska verktyg och för att beräkna energiförbrukning och inneklimat pårumsnivå. Man bör tidigt inkludera utformning av t ex ventilation ocheventuella maskinrum då de kan ha stor inverkan på energiförbrukningen. Man utför prestandaanalyser av energi och inneklimat innan man fryserdesign av klimatskärm och VVS så att resultatet kan guida konstruktörer ochinstallatörer i den slutliga utformningen av systemhandlingarna. Man i driftfasen utför en mer automatisk och kontinuerlig jämförelse mellansimulerad och verklig energiförbrukning för att bekräfta att byggnadenuppfyller initiala krav samt för att inhämta data och erfarenheter för vidareoptimering eller andra framtida projektFörändring sker i och med att beställaren möjliggör en miljö som initierar ochstödjer en hög grad av samverkan och integration mellan inblandade aktörer, därtyngden på beslutsfattandet flyttas till ett tidigare skede, där rätt kompetenserkan komma in vid rätt tillfälle och där fokus är på slutprodukten och desslivscykel och inte på avskilda åtaganden

  • 274. Dehlin, Stefan
    et al.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    A concurrent product development process using virtual prototypes2008Conference paper (Refereed)
  • 275.
    Dehlin, Stefan
    et al.
    Luleå tekniska universitet.
    Olofsson, Thomas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Construction Engineering.
    An evaluation model for ICT investments in construction projects2008In: Electronic journal of information technology in construction, ISSN 1403-6835, E-ISSN 1400-6529, Vol. 13, p. 343-361Article in journal (Refereed)
    Abstract [en]

    Even though Information and Communication Technology (ICT) investments in construction projects generally represent minor commitments of project resources by comparison to the full project cost, the value or impact on the profitability of the project are generally not considered. Also, many of the investment decisions are poorly thought through or examined. Investments decision taken during the procurement phase often merely based on intuition and rough estimations of the future costs and risks. Also, many of the traditionally used appraisal approaches have been shown inadequate in anticipating the consequences of such an investment. As a result, the investment is too often assumed to be negative since the benefits are not proper evaluated, included and weighted against the costs and risks the investment is expected to generate. Poor decision-basis does not only affect the actual decision-making in a particular project but also, in the long run, the motivation to innovate and to introduce new ICT tools and working methods into the construction industry. In view of this, a new project-oriented evaluation model is developed for the purpose to provide for a structure and a work routine to be used by a multidisciplinary project team to evaluate the implications of realizing ICT investments in construction projects. Although primarily aimed at establishing future benefits and costs the model may very well be used for follow-ups. The models' application is illustrated using a case study of a construction project using 3D and VR for coordination and evaluation. The results based on interviews and rough estimates on the "safe side" show that benefit of the ICT investment for the case study project was much higher compared with the cost for the project. The shift in focus from costs/benefits for the individual stakeholders to costs/benefits for the project gives a momentum to optimize the use of a new ICT tools in construction. This will surely affect the processes and the contractual environment in the project, since it has to support sharing of information and achieved benefits and the costs of the investment in the project.

  • 276.
    Deleskog, Adam
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Svantorp, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Problematik vid användning av väderskydd2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The demand for weather protected scaffolding in building production has increased during recent years. A consequence when using weather protection is that the scaffolding will have to endure bigger loads from wind and snow, which increases the risk of a collapse. During the winter of 2016/2017 two weather protected scaffoldings collapsed by heavy snowfall at the site of KTH (the Royal Institution of Technology) in Stockholm, Sweden. This gave the authors the idea of this report.

    The purpose of the report is to investigate why weather protected scaffoldings collapses by examining the procedure of building and using weather protection in production and also a study of the current regulations regarding the subject. The report was made in cooperation with Skanska and therefore only the company’s intern procedure was studied.

    During the studies of the Swedish Work Environment Authority’s statute book a conclusion was made that the statute book was sufficient enough to prevent accidents to occur. The studies also showed that Skanska’s safety work is well developed with it’s detailed working methods for a safe work environment regarding scaffolding and weather protection. Skanska has made own additions to the statute book in order to improve safety even more.

    The report also shows a need of an investigation made of the Swedish Work Environment Authority when a weather protected scaffolding has collapsed to prevent serious accidents in the future.

  • 277.
    Delic, Damir
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Hadzic, Amer
    Halmstad University, School of Business and Engineering (SET).
    Energibesiktning av förskolor: En fallstudie av Bygg- och installationsteknisk undersökning på förskolor i Falkenberg2011Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 278.
    Delvret, Anton
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Holmqvist, Niclas
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Ventilation i förskolor - kostnader och energiprestanda.: Kalkyler och energiberäkningar2016Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 279.
    Delvret, Anton
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Holmqvist, Niclas
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Ventilation i förskolor-kostnader och energiprestanda: Kalkyler och energiberäkningar2016Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 280.
    Desgrées du Loû, Antoine
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies.
    Value for Money evaluation in PPPs: difficulties and developments2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Public private partnerships (PPPs) are procurement models used in the provision of public infrastructures and involving private, as opposed to public, finance. The PPP model differs from the traditional public procurement model in this sense and in the unprecedented degree to which the private sector is involved.

    All things being equal, the rationale for choosing a PPP instead of a traditional public procurement model is if it provides a better Value for Money. As a result, a crucial issue to address is to find the key drivers of Value for Money in PPP projects and most importantly, to analyze the relationships between those key drivers and the complex notion of Value for Money.

    This study is based on a large overview of the literature together with contributions of informal interviews and my own opinions. Emphasis is put on the importance of risk management from financiers’ perspective and its consequences on Value for Money. The findings highlight the current problems in the Value for Money assessment that make the analysis hardly reliable. Good and bad practices in Value for Money assessment are discussed and potential solutions and guidance toward more Value for Money are provided. 

  • 281.
    Djärv, Jesper
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Israelsson, Daniel
    Dalarna University, School of Technology and Business Studies, Construction.
    Uttorkning i betong: En jämförelse av uttorkningstider mellan bascement och byggcement.2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In construction projects, moisture problems have been discovered in concrete slabs where plastic mats have been released from the substrate. One of the problems reported in the media is the change from Portland cement to fly ash cement. Fly ash cement is a cement with 14% fly ash mixed with portland clinker. The reason that cement manufacturers use fly ash, which is a residual product from powder-fired coal power plants, is that it reduces the amount of portland clinkers that release large amounts of carbon dioxide during production.

    Cement is the concrete binder and when fly ashes are used, less amount of water is bound in the concrete's hydration process. To investigate the difference in dehydration found in concrete with fly ash cement and Portland cement, two concrete samples were obtained with the same concrete recipe and VCT numbers, but with different cement types. These concrete samples were stored in a heated local with low relative humidity. Moisture measurements were carried out according to the current regulations. These results were compared with the moisture predictions from TorkaS and BI Dry, which are the most commonly used moisture calculation programs. At the same time, various actors from the construction industry were interviewed to investigate how they perceived the problem of dehydration in concrete.

    The moisture measurements showed no significant difference between concrete with base cement and building cement. When compared with the forecasted values from the moisture calculation programs, it was found that the Dry values were very close to the measured moisture values, while BI Dry's values were well below the measured values. The interviews revealed that the construction industry has many questions about dehydration in concrete. On the other hand, there are difficulties in determining what is the basis for the problems. If there is a change from the portland cement to the fly ash cement, or the handling of the concrete at an early stage after the casting affects. However, if the moisture issue is taken up early in the construction process, it is possible to save both time and money. The construction industry needs to be educated how the process of desiccation works to increase understanding of the problem.

  • 282.
    Dobo, Daniel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Östberg, Dennis
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Masshantering vid hamnbyggnation: Logistik och metoder2016Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 283.
    Dodik, Josip
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Dodik, Mario
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    En jämförelse av 6 aktuella bostadsområden i Sverige med uttalad inriktning på hållbart stadsbyggande2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Under det senaste århundradet har det dykt upp många miljöproblem som har lett till att vi idag måste fokusera mer på en hållbar utveckling av våra städer.

    Allt fler människor väljer att bo i städer och därför är det viktigt för vår framtid att stadsplaneringen blir så hållbar som möjligt.

    Denna rapport beskriver och värderar 6 olika hållbara stadsdelar i Sverige. Dessa har identifierats och värderats utifrån 6 hållbarhetsaspekter som anses vara viktiga.

    Studierna har begränsats till hållbar utveckling inom stadsplanering, de pa- rametrar som tas upp i examensarbetet ”En jämförelse av 6 aktuella bo- stadsområden i Sverige med uttalad inriktning på hållbart stadsbyggande” är; Transport, Social Hållbarhet, Grönskande Utomhusmiljö, Hållbara Transporter, Hållbart Energisystem, Miljöanpassade Bostäder & Lokaler, Hållbart Vatten & Avlopp och Hållbar Återvinning. 

  • 284.
    Dodoch, Antonio
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Alaiya, Mayowa
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Minskning av byggfel genom väl utförda arbetsberedningar: Optimering av arbetsberedningar i syfte att motverka byggfel2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sammanfattning

     

    Oönskade tilläggs- och ändringsarbeten uppkommer i byggproduktionen som medför ekonomiska påföljder och förseningar i tidplanen. Dessa arbeten går under det gemensamma namnet ÄTA-arbeten (Ändrings-, tilläggs- och avgående arbeten) och orsakas av diverse anledningar. En av orsakerna till uppkomsten av de oönskade ÄTA-arbetena är svårigheterna med att framställa utförliga arbetsberedningar.

     

    Rapporten syftar till att redogöra hur effektivare arbetsberedningar kan förhindra uppkomsten av oönskade ÄTA-arbeten samt hur arbetsberedningarna kan förbättras. Under arbetets gång har svar till formulerade frågeställningar frambringats genom enkätundersökningar och intervjuer och diskussioner kring ämnet har förts utifrån det egna medverkandet i ett antal arbetsberedningar. Rapporten avgränsas till platsbesök på två projekt; Projekt Driftområde Arlanda samt och Kontorsfastighet Hus 4 Nya Danderyds Centrum.

     

    Analyserna och slutsatserna presenteras i rapportens avslutande delar och ger en uppfattning på hur arbetsberedningar står i relation till uppkomsten av oönskade ÄTA-arbeten. Med väl utförda arbetsberedningar avser man att skapa bästa möjliga förutsättningar för ett arbetsmoment och på så sätt minimerar risken för uppkomsten av oönskade ÄTA-arbeten. Styrning, planering, hantering av tidsbrist, resurstillgänglighet och engagemang är faktorer som i stor utsträckning styr huruvida bra eller dåligt en arbetsberedning blir. Dessa ämnen kommer att behandlas mer ingående i rapporten.

     

    Rekommendationer kring hur arbetsberedningar kan förbättras och effektiviseras utifrån olika aspekter gällande arbetsplatsens utformning, engagemanget hos arbetarna, erfarenhetsåterföring samt dokumentationen av arbetsberedningarna redovisas i rapporten.

     

  • 285.
    Dodoo, Ambrose
    et al.
    Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Gustavsson, Leif
    Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Sathre, Roger
    Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Carbon implications of end-of-life management of building materials2009In: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 53, no 5, p. 276-286Article in journal (Refereed)
    Abstract [en]

    In this study we investigate the effects of post-use material management on the life cycle carbon balance of buildings, and compare the carbon balance of a concrete-frame building to that of a wood-frame building. The demolished concrete is either landfilled, or is crushed into aggregate followed by exposure to air for periods ranging from 4 months to 30 years to increase carbonation uptake of CO2. The demolished wood is assumed to be used for energy to replace fossil fuels. We calculate the carbon flows associated with fossil fuel used for material production, calcination emission from cement manufacture, carbonation of concrete during and after its service life, substitution of fossil fuels by recovered wood residues, recycling of steel, and fossil fuel used for post-use material management. We find that carbonation of crushed concrete results in significant uptake of CO2. However, the CO2 emission from fossil fuel used to crush the concrete significantly reduces the carbon benefits obtained from the increased carbonation due to crushing. Stockpiling crushed concrete for a longer time will increase the carbonation uptake, but may not be practical due to space constraints. Overall, the effect of carbonation of post-use concrete is small. The post-use energy recovery of wood and the recycling of reinforcing steel both give higher carbon benefit than the post-use carbonation. We conclude that carbonation of concrete in the post-use phase does not affect the validity of earlier studies reporting that wood-frame buildings have substantially lower carbon emission than concrete-frame buildings.

  • 286.
    Dodoo, Ambrose
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Gustavsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Sathre, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Carbon implications of end-of-life management of building materials2009In: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 53, no 5, p. 276-286Article in journal (Refereed)
    Abstract [en]

    In this study we investigate the effects of post-use material management on the life cycle carbon balance of buildings, and compare the carbon balance of a concrete-frame building to that of a wood-frame building. The demolished concrete is either landfilled, or is crushed into aggregate followed by exposure to air for periods ranging from 4 months to 30 years to increase carbonation uptake of CO2. The demolished wood is assumed to be used for energy to replace fossil fuels. We calculate the carbon flows associated with fossil fuel used for material production, calcination emission from cement manufacture, carbonation of concrete during and after its service life, substitution of fossil fuels by recovered wood residues, recycling of steel, and fossil fuel used for post-use material management. We find that carbonation of crushed concrete results in significant uptake of CO2. However, the CO2 emission from fossil fuel used to crush the concrete significantly reduces the carbon benefits obtained from the increased carbonation due to crushing. Stockpiling crushed concrete for a longer time will increase the carbonation uptake, but may not be practical due to space constraints. Overall, the effect of carbonation of post-use concrete is small. The post-use energy recovery of wood and the recycling of reinforcing steel both give higher carbon benefit than the post-use carbonation. We conclude that carbonation of concrete in the post-use phase does not affect the validity of earlier studies reporting that wood-frame buildings have substantially lower carbon emission than concrete-frame buildings.

  • 287.
    Dodoo, Ambrose
    et al.
    Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Gustavsson, Leif
    Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Sathre, Roger
    Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Energy implications of end-of-life options for building materials2008In: First International Conference on Building Energy and Environment, Proceedings Vols 1-3, Dalian, China: Dalian University Technology Press , 2008, p. 2025-2032Conference paper (Refereed)
    Abstract [en]

    The energy flows associated with the materials comprising a building can be a significant part of the total energy used in a building's life cycle. Buildings have finite life spans, and the materials from demolished buildings can be either a burden that must be disposed, or a resource that can be used. In this paper we analyse the end-of-life energy impacts of concrete, steel and wood. End-of-life options considered include reuse; recycling; downcycling; energy recovery; and disposal in landfill. We follow the life cycles of the building materials from the acquisition of natural resources through to the end of the product's life cycle. We identify possibilities and constraints for integrating more effective end-of-life material processing options into existing industrial systems.

  • 288.
    Dodoo, Ambrose
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Gustavsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Sathre, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Energy implications of end-of-life options for building materials2008In: FIRST INTERNATIONAL CONFERENCE ON BUILDING ENERGY AND ENIVRONMENT, PROCEEDINGS VOLS 1-3, Dalian, China: Dalian University Technology Press , 2008, p. 2025-2032Conference paper (Refereed)
    Abstract [en]

    The energy flows associated with the materials comprising a building can be a significant part of the total energy used in a building's life cycle. Buildings have finite life spans, and the materials from demolished buildings can be either a burden that must be disposed, or a resource that can be used. In this paper we analyse the end-of-life energy impacts of concrete, steel and wood. End-of-life options considered include reuse; recycling; downcycling; energy recovery; and disposal in landfill. We follow the life cycles of the building materials from the acquisition of natural resources through to the end of the product's life cycle. We identify possibilities and constraints for integrating more effective end-of-life material processing options into existing industrial systems.

  • 289.
    Dodoo, Ambrose
    et al.
    Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Gustavsson, Leif
    Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Sathre, Roger
    Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Life cycle primary energy implication of retrofitting a wood-framed apartment building to passive house standard2010In: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 54, no 12, p. 1152-1160Article in journal (Refereed)
    Abstract [en]

    Here we analyze the life cycle primary energy implication of retrofitting a four-storey wood-frame apartment building to the energy use of a passive house. The initial building has an annual final energy use of 110 kWh/m(2) for space and tap water heating. We model improved thermal envelope insulation, ventilation heat recovery, and efficient hot water taps. We follow the building life cycle to analyze the primary energy reduction achieved by the retrofitting, considering different energy supply systems. Significantly greater life cycle primary energy reduction is achieved when an electric resistance heated building is retrofitted than when a district heated building is retrofitted. The primary energy use for material production increases when the operating energy is reduced but this increase is more than offset by greater primary energy reduction during the operation phase of the building, resulting in significant life cycle primary energy savings. Still, the type of heat supply system has greater impact on primary energy use than the final heat reduction measures.

  • 290.
    Dodoo, Ambrose
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Gustavsson, Leif
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Sathre, Roger
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Life cycle primary energy implication of retrofitting a wood-framed apartment building to passive house standard2010In: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 54, no 12, p. 1152-1160Article in journal (Refereed)
    Abstract [en]

    Here we analyze the life cycle primary energy implication of retrofitting a four-storey wood-frame apartment building to the energy use of a passive house. The initial building has an annual final energy use of 110 kWh/m(2) for space and tap water heating. We model improved thermal envelope insulation, ventilation heat recovery, and efficient hot water taps. We follow the building life cycle to analyze the primary energy reduction achieved by the retrofitting, considering different energy supply systems. Significantly greater life cycle primary energy reduction is achieved when an electric resistance heated building is retrofitted than when a district heated building is retrofitted. The primary energy use for material production increases when the operating energy is reduced but this increase is more than offset by greater primary energy reduction during the operation phase of the building, resulting in significant life cycle primary energy savings. Still, the type of heat supply system has greater impact on primary energy use than the final heat reduction measures.

  • 291.
    Dodoo, Ambrose
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Sathre, Roger
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lifecycle carbon implications of conventional and low-energy multi-storey timber building systems2014In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 82, p. 194-210Article in journal (Refereed)
    Abstract [en]

    A consequential-based lifecycle approach is used here to explore the carbon implications of conventional and low-energy versions of three timber multi-storey building systems. The building systems are made of massive wood using cross laminated timber (CLT) elements; beam-and-column using glulam and laminated veneer lumber (LVL) elements; and prefabricated modules using light-frame volume elements. The analysis encompasses the entire resource chains during the lifecycle of the buildings, and tracks the flows of carbon from fossil energy, industrial process reactions, changes in carbon stocks in materials, and potential avoided fossil emissions from substitution of fossil energy by woody residues. The results show that the low-energy version of the CLT building gives the lowest lifecycle carbon emission while the conventional version of the beam-and-column building gives the highest lifecycle emission. Compared to the conventional designs, the low-energy designs reduce the total carbon emissions (excluding from tap water heating and household and facility electricity) by 9%, 8% and 9% for the CLT, beam-and-column and modular systems, respectively, for a 50-year lifespan located in Växjö. The relative significance of the construction materials to the fossil carbon emission varies for the different energy-efficiency levels of the buildings, with insulation dominating for the low-energy houses and plasterboard dominating for the conventional houses.

  • 292.
    Dorn, Michael
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kozłowski, Marcin
    Silesian University of Technology, Poland.
    Serrano, Erik
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Enquist, Bertil
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Development of large-scale load-bearing timber-glass structural elements2014In: WCTE 2014 - World Conference on Timber Engineering: Proceedings, 2014Conference paper (Refereed)
    Abstract [en]

    The building industry demands ever more effective structural elements with a multitude of requirements at the same time. There is increasing interest for load-bearing glass elements which can be deployed in timber structures, e.g. in the outer façade or as column or beam elements within the building. In an on-going research project, the materials glass, timber and the adhesive combining the former have to be selected to fit each other but also suit the application. The mechanical properties are studied individually as well as in combined small-scale specimens experimentally. Furthermore,large-scale tests on beams and shear walls are performed. This is accompanied by numerical analysis to study a wide range of dimensions and variations as well as specific design situations. The final output of the project will be prototypes to beused in showcase projects.

  • 293.
    Draganovic, Almir
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Bleeding and Filtration of Cement-Based Grout2009Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Grouting is a common method of sealing rock around tunnels to reduce or stop water inflow. Successful grouting significantly minimizes the maintenance cost and safety of the tunnel. Some questions about bleeding and penetrability of the grouts have to be examined more closely to carry out a successful grouting.

    Bleeding of cement-based grout is a complex problem. Measuring methods used today originate from the measuring of the bleeding of cement pastes used in ordinary building industry. Whether bleeding measured with a standard method is relevant for bleeding in small fractures in rocks is one of the main questions in this study. The aim of the study is to illustrate what really happens with a grout during bleeding and which factors and processes influence it. In this way relevant measuring methods can be developed as well as the knowledge regarding interpretation of the measured results. The study has shown the most important factors which governs bleeding in cement-based grout. It has also shown that the results measured with standard methods are not relevant for bleeding of grout in rock joints and that voids in the joints caused by bleeding could be refilled during grouting itself.

    An important aspect of grouting is penetration of the grout. The penetration is defined as the length of how far grout penetrates in the rock through fractures from a bore hole. Filtration of the grout is a result of a plug building at fracture constrictions which reduces the penetrability of the grout. This is the other important issue discussed in the study which examines the question whether this can be measured by some measuring method and which factors and processes influence penetrability and filtration. A hypothesis of how the factors w/c ratio, pressure and relative constriction influence penetrability are presented and tested by special constructed measuring equipment. The results obtained by this measuring equipment are compared with the results measured with a penetrability meter.

  • 294.
    Du, Guangli
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Safi, Mohammed
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges. ÅF Infrastructure AB, Sweden.
    Pettersson, Lars
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges. Skanska Sverige AB, Sweden.
    Karoumi, Raid
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Life cycle assessment as a decision support tool for bridge procurement: environmental impact comparison among five bridge designs2014In: The International Journal of Life Cycle Assessment, ISSN 0948-3349, E-ISSN 1614-7502, Vol. 19, no 12, p. 1948-1964Article in journal (Refereed)
    Abstract [en]

    The conventional decision-making for bridges is mostly focusing on technical, economical, and safety perspectives. Nowadays, the society devotes an ever-increased effort to the construction sector regarding their environmental performance. However, considering the complexity of the environmental problems and the diverse character of bridges, the related research for bridge as a whole system is very rare. Most existing studies were only conducted for a single indicator, part of the structure components, or a specific life stage. Life Cycle Assessment (LCA) is an internationally standardized method for quantifying the environmental impact of a product, asset, or service throughout its whole life cycle. However, in the construction sector, LCA is usually applied in the procurement of buildings, but not bridges as yet. This paper presents a comprehensive LCA framework for road bridges, complied with LCA ReCiPe (H) methodology. The framework enables identification of the key structural components and life cycle stages of bridges, followed by aggregation of the environmental impacts into monetary values. The utility of the framework is illustrated by a practical case study comparing five designs for the Karlsnas Bridge in Sweden, which is currently under construction. This paper comprehensively analyzed 20 types of environmental indicators among five proposed bridge designs, which remedies the absence of full spectrum of environmental indicators in the current state of the art. The results show that the monetary weighting system and uncertainties in key variables such as the steel recycling rate and cement content may highly affect the LCA outcome. The materials, structural elements, and overall designs also have varying influences in different impact categories. The result can be largely affected by the system boundaries, surrounding environment, input uncertainties, considered impact indicators, and the weighting systems applied; thus, no general conclusions can be drawn without specifying such issues. Robustly evaluating and ranking the environmental impact of various bridge designs is far from straightforward. This paper is an important attempt to evaluate various designs from full dimensions. The results show that the indicators and weighting systems must be clearly specified to be applicable in a transparent procurement. This paper provides vital knowledge guiding the decision maker to select the most LCA-feasible proposal and mitigate the environmental burden in the early stage.

  • 295.
    Duberg, Roland
    et al.
    Luleå University of Technology.
    Borgbrant, Jan
    Utvärderingsrapport CDU - Centrum för forskning och utbildning i drift och underhåll av infrastruktur2002Report (Other academic)
    Abstract [sv]

    Sammanfattning och slutsatser De centrala frågeställningarna som utgör utgångspunkt för utvärderingen är redovisade i avsnittet "Centrala frågeställningar" i denna rapport. Frågeställningarna kan kortfattat rubriceras som följer: Styrformens betydelse för berörda aktörer Forskningens resultat och nytta Jubileumsprofessurens betydelse för CDU:s framtid CDU:s påverkan av samarbetet mellan huvudintressenterna Frågor som har konsekvenser för aktörerna på kort och lång sikt

  • 296.
    Dudenhöfer, Dennis
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    En kostnadsjämförelse mellan hyrd och köpt utrustning2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the swedish construction business, most contractors rent their equipment from renting companies. There are different reasons for that, the most significant reason being that companies do not want to tie up capital. Rekab Entreprenad AB is one of those companies. Andreas Nilsson, project manager at Rekab, now wants to investigate which is more profitable, buying own equipment or renting. The purpose of this study perform a case study for Rekab Entreprenad AB in Umeå. Using websites of companies that are partners with Rekab, prices for buying different equipment were compared to rent prices. Different factors like rent for storage, transportation and insurance were also taken into consideration. Also suggestions were given for more environment-friendly equipment handling. The economic result is divided into two parts: the individual cost for every piece of equipment and general costs. Examples for general cost are: rent for storage, insurance, transportation and other factors that are not dependent on quantity of equipment. Results for individual cost of every equipment varies, but generally the cost for buying machines is one fourth of the cost for renting. The . Also the general cost is to be added to that number. A factor to take into account is storage rent, which is already being paid by Rekab, and therefore is not an extra cost when buying own equipment. In conclusion, the profitability in buying eqipment depends on the equipments quantity. In Rekabs case, according to this study, buying equipment is much more economically profitable than renting equipment. A profitability as high as the study suggests must be questioned by the fact that Rekab is still renting equipment. That question can be explained with hidden costs, which often are hard to put a pricetag on. A discussion about these hidden costs is presented in the discussion section.

  • 297.
    Dusseau, Foster
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies. ABE department; exchange student from ESTP Paris.
    Oslo- Stockholm High Speed Railway: An up in the air project2012Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The objective of this paper is to shed a light on a High-speed Railway (HSR) study project in the corridor Stockholm-Oslo, and investigate the global context in which it has grown. Priority Project 12 (PP12), commonly named “The Nordic Triangle”, is a project within the Trans-European Transport Network (TEN-T) program, a European program aiming at establishing an efficient transport network, for competitiveness and employment in Europe. The Nordic Triangle aims at linking the Nordic countries, Sweden, Norway, Denmark and Finland and their capitals to each other and improving passenger and freight transport, both rail and road, between the central Europe, the Baltic countries and Russia. The cornerstone of this program in Sweden is the development of three main axes: Stockholm–Katrineholm–Laxa–Swedish–Norwegian boarder; Katrineholm/Jarna–Norrköping–Malmö; and Malmö–Gothenburg–Swedish–Norwegian border. Of course, this extension to the Swedish-Norwegian boarder targets to reach Oslo, the Norwegian capital.

    What was expected in theory mismatches with the current situation and the future expectations on this project. It proves that Sweden, throughout the PP12, has concentrated its railway upgrades to the two other axes and has made few efforts to improve the Oslo–Stockholm line. Political decisions in terms of railway network development are more focused on the North-South axes, which represent an undeniable opening to Central Europe.

    At the same time the Norwegian Ministry of Transport has launched in 2010 an overall High Speed Rail Assessment to study different route alternatives for the creation of a first new HSR system. Among them is the Stockholm-Oslo route. It is curious to see that Norway focuses on a project that is not on the agenda of the European Commission and it is important to try to understand why and to know if such a project is economically viable.

    The conclusion is that this current implementation reflects the Swedish willingness to develop its railway network, and especially its high-speed network, to the South, which embodies a front door to Central Europe. Thus, since the beginning of the development of the Nordic Triangle, it seems probable Sweden had in mind not to upgrade all the line to Oslo, but only half the way.

    As regards the viability of the HSR line, it could not be economically viable because the revenue generated could not offset these former costs. An insufficient demand would be the main problem. Investing in a HSR on this corridor is certainly not the most reasonable decision, neither for Norway nor for Sweden.

  • 298.
    Dzafic, Amir
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Stölder och inbrott på byggarbetsplatser: En studie om risker och konsekvenser inom NCC:s produktion2017Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Theft and brake-ins at Swedish construction sites is a very common problem that mainly occurs during the production phase of building. The fractures that occur are not limited to a specific area but they also occur throughout the entire country. However, the areas around the major cities and larger national and European roads are most affected. Many companies are not prepared for the costs of a theft or burglary and there are no clear procedures for dealing with the situation that occurs. Stolen gods and burglaries is a waste of production that the companies should work harder to remove or at least reduce. The waste is so big that about 7000 burglaries and robberies from Swedish workplaces are reported annually. According to other studies, these 7000 burglars render a cost of 1.4 billion SEK annually for the Swedish construction industry.

    The work has been carried out and with the help of NCC Sverige AB section Värmland. The main purpose and goal of this work is to make NCC workplaces safer and more efficient by reducing the risk of a theft or burglary. The goal is also to give an increased understanding of what it means and what happens in the production phase after thefts and burglaries at construction sites.

    The method used to obtain the right information is primarily interviews and questionnaire surveys, but discussions have also been held with most supervisors, site managers and several other workers. In addition, site visits have been carried out at construction sites where routines have been investigated, placement of containers and security in and around the site offices as well as preventive measures and the risks involved on the site.

    The subject is quite unexplored, but there are some studies that have been done over the years. Svenska Byggbranschens Utveklingsfond, SBUF, has done several information papers and implemented a number of projects that deal with theft and burglaries on Swedish construction sites. Another major study that has been carried out is "Stölder och inbrott på byggarbetsplatser – omfattning, skadeverkan och risk", a study conducted at Malmö University on behalf of FoU Väst. These studies form the basis of my work and this is where knowledge and information about the subject has been retrieved.

    The investigations showed that a workplace that is close to major roads or which is located in a way that makes the insight poor, is at the highest risk of being affected by burglaries. Furthermore, it is possible to say that bad lighting, badly marked alarm signs and a workplace that is not properly protected in the form of proper fences and locks lies in a high-risk zone in case of a theft. There is a lot to work to do with the companies when it comes to routines and preventive measures. For example, one would be able to invest in a much more burglary fence which would make work difficult for any thieves.

    Given the pressure on building homes and other buildings in Sweden today, the risks will increase to be exposed by a burglary or a theft. This is an important factor that makes the topic interesting for companies in the industry so that they can get well prepared for each construction site in terms of prevention measures.

  • 299.
    Dzamalija, Zada
    Halmstad University, School of Business and Engineering (SET), Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Sustainability, Innovation and Management in Building (SIMB).
    Den fysiska arbetsmiljön på väg- och anläggningsprojekt: Hur styrs säkerhetsarbetet på Skanska för att uppnå bättre arbetsmiljö2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 300.
    Döse, Magnus
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Silfwerbrand, J.
    Jelinek, C.
    Trägårdh, Jan
    RISE, SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Hållbara byggnadsverk.
    Isaksson, M.
    Naturally occurring radioactivity in some Swedish concretes and their constituents - Assessment by using I-index and dose-model2016In: Journal of Environmental Radioactivity, ISSN 0265-931X, E-ISSN 1879-1700, Vol. 155-156, p. 105-111Article in journal (Refereed)
    Abstract [en]

    The reference level for effective dose due to gamma radiation from building materials and construction products used for dwellings is set to 1 mSv per year (EC, 1996, 1999), (CE, 2014). Given the specific conditions presented by the EC in report 112 (1999) considering building and construction materials, an I-index of 1 may generate an effective dose of 1 mSv per year. This paper presents a comparison of the activity concentrations of 4 0K, 226Ra and 232Th of aggregates and when these aggregates constitute a part of concrete. The activity concentration assessment tool for building and construction materials, the I-index, introduced by the EC in 1996, is used in the comparison. A comparison of the I-indices values are also made with a recently presented dose model by Hoffman (2014), where density variations of the construction material and thickness of the construction walls within the building are considered. There was a ~16-19% lower activity index in concretes than in the corresponding aggregates. The model by Hoffman further implies that the differences between the I-indices of aggregates and the concretes' final effective doses are even larger. The difference is due, mainly to a dilution effect of the added cement with low levels of natural radioisotopes, but also to a different and slightly higher subtracted background value (terrestrial value) used in the modeled calculation of the revised I-index by Hoffman (2014). Only very minimal contributions to the annual dose could be related to the water and additives used, due to their very low content of radionuclides reported.

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