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  • 201.
    Johannesson, Gudni
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Development of various low-ex system components and their integration2007In: IAQVEC 2007 Proceedings - 6th International Conference on Indoor Air Quality, Ventilation and Energy Conservation in Buildings: Sustainable Built Environment, IAQVEC 2007; Sendai; Japan; 28 October 2007 through 31 October 2007, 2007, p. 1107-1114Conference paper (Refereed)
    Abstract [en]

    The present paper deals with modeling of various low-exergy system components and their integration into the energy system for buildings and small communities. The exergy content of a certain amount of energy is defined as the part of this energy that can be used to produce mechanical energy. The quality of a certain amount of energy is defined as the relative exergy content of this energy. Most of our buildings with their heating and cooling systems today are built for conversion of high quality energy sources to low quality use with a huge destruction of the available exergy as a result. Globally we have a huge potential for transforming our processes to more efficient use of the exergy and also for feeding our processes directly from renewable energy sources without the use of high quality energy sources. To develop our building concepts towards a low exergy building we have to analyze all the processes for energy conversion that take place through the operation of the building, to bring down the needed level of quality for the energy used and then make a holistic analysis of the system. Different processes for energy conversion in buildings are discussed especially giving the potential for saving energy and shifting the energy use to lower quality levels, i.e. in many cases to reduce the temperature levels needed for heating and cooling. The major obstacle for an extensive and effective use of renewable energy sources is the investment needed to be able to store heating and cooling energy in time. The paper gives a system concept under evaluation were the ground under the floor slab on grade is used as heat reservoir for the building. The main advantage of the system would be lower investment cost and at the same time give possibilities more effective annual storage compared to a single borehole. The paper also exemplifies how recent finite element technology where multiple physical phenomena can be studied simultaneously can be utilsed for design of low exergy components.

  • 202.
    Johansson, Lisa
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Nilsson, Anton
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Arbetsmiljö ur Entreprenörens perspektiv: En utvärdering av den nuvarande situationen och förslag på utveckling2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The report compiles a survey of how different occupational groups at the building site are working with workplace environment at various IN3PRENÖR building sites. It shows that the difficulties in the workplace environment work are to communicate the goals and the way towards these goals. The difficulties are also in communicating shortcomings between the different occupational groups. The conclusion from the interviews and survey results is that the employees thrive in their workplace, disregarding weather it’s in the projects or the overall company.The construction industry is one of the most accidentally affected industries, and therefore is the workplace environment work extra important to minimize the risks of one of the workers being injured. The industry is regulated by the Work Environment Act and is the only profession mentioned specifically in the Act. In addition to the Work Environment Act, it is also regulated by different regulations. There are eighties, of which some twenty-thirty affect construction.The process of the result has consisted of site visits of seven of IN3PRENÖR's construction sites. The projects are varied, ranging from refurbishments and additions to schools to relocation of smoke ducts and tenant servants to government with EU standards instead of Swedish standards. These site visits included interviews, surveys and observations of the construction site. The work has then been compiled and analyzed to find out the shortcomings and how they can be improved.

  • 203.
    Josephson, Anna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Lundström, Sara
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Stadens bortglömda plats: En studie om tekniska möjligheter och sociala och ekologiska fördelar med bebyggelse av platser intill brofästen2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 204.
    Josephson, Anna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Lundström, Sara
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    STADENS BORTGLÖMDA PLATS: En studie om tekniska möjligheter och sociala och ekologiska fördelarmed bebyggelse av platser intill brofästen2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In today’s cities there are many forgotten places whose full potential is not being met.The social sustainability of the city is often disadvantaged by these places as theycause insecurity, discomfort and vulnerability to passers-by, especially women. Aforgotten place that is recurring in Swedish cities are so-called bridge abutment-sites,that is, places under bridges next to the abutment. The purpose of the study is todemonstrate the potential of these non-places at bridge abutments in urban environmentsand to highlight the conditions, problems and possibilities as well as the socialand ecological benefits of a development of these sites.The study shows that building these sites can create safe and inclusive areas to stayin, as well as increase the perceived security of the site, especially for women. Housingthat in some way activates the site helps to create social meetings in the city. Thebuilding can also act crime preventive, partly due to an increased flow of people onthe site. The ecological benefits obtained are that urban greenery, and thus importantecosystem services, can be preserved to a greater extent as already impermeable surfacesare used in densification in urban environments instead of green areas. Greeneryand ecosystem services provide important recreational and social values for the city’sinhabitants and also benefit the presence of biodiversity.All laws, requirements and regulations that apply to planning, design and constructionof buildings in Sweden, also applies to these locations. The study finds that there areno general prohibitions or regulations that regulate the construction or non-constructionof bridge abutments. Bridge abutment-sites seem to have been forgotten or previouslynot needed to be taken into account in the densification of Swedish cities, sincethere have been other land to exploit. Another reason why the sites have not been usedis due to preconceived opinions in the construction industry. The preconceptions areoften based on assumptions beyond professional knowledge, rather than facts andexperience. In order for the places to be built, a change of attitude in operators in theconstruction industry is required.The function-types of community center, housing and temporary accommodationare all possible to construct at these sites, with the exception of housing at the bridgeplaces where noise levels and daylight emissions do not meet the requirements. Thebest-suited function-type for many urban bridge abutment-sites is a communitycenter, where a mix of functions that require both consumption and non-consumptionwould best benefit social sustainability in the area.The study shows that construction of the bridge abutment-sites is possible if parameters,as mentioned in the study, are considered and met. In order to enable such aproject, a change in attitude and solid cooperation between several operators in theindustry are required. The cooperation between authorities and operators in the constructionindustry would not only benefit the possible development of these sites, butall construction projects in Sweden.

  • 205.
    Jävenhag, Henrik
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Gawell, Ida
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Kapacitetsmässiga och ekonomiska konsekvenser av en ökad standarddimension på avloppsledningar2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 206.
    Kader, Aza
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Yousif, Peter
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Förvärmning av tilluften med återvunnen värme2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, it is common for district heating companies to base their taxi on the power requirement of the property. Power taxation method differs between different district heating suppliers. However, the top performance requirements for the properties are a common denominator for the companies when debit documentation is decided.In Sweden, there is existing technology that reduces the power requirement by preheating outdoor air, which reduces frost formation in the heat exchanger and improves its efficiency. This technique uses geothermal energy as a source of heat using boreholes with a depth of up to 230 meters. Technology is called HSB-FTX and is a passive preheating of the supply air.This report aims at investigating the possibility of power reduction and condensation reduction during the coldest winter days by preheating the supply air with recycled heat from stored waste water. In the project, a standard FTX system has been matched with a complementary system to an existing FTX system, which is basically based on a micro-heat pump that recovers heat energy from stored waste water. The comparison has been simulated in the IDA ICE (Indoor Climate Energy) program and the simulation period was from December 2016 to March 2017. The simulations have shown that there will be a reduction in energy use and peak loads during the coldest months. In Stockholm, peak loads are reduced by 10,9 kW and in Malmö by 4,5 kW. The energy use decreases by 14 000 kWh in Stockholm and in Malmö by 11 000 kWh. This result shows cost saving of the installed power of approximately 5 500 kr/year and the energy saving by 10 000 kr/year, which proved to be profitable. The cost estimate was made for Stockholm and showed that reduction of energy use and efficiency was sufficient to make it profitable.

  • 207.
    Kakkavos, Evangelos
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Beräkningsmodell för sprickbredd hos vrid- och tvärkraftssprickor: Spänningar i plant spänningstillstånd2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 208.
    Karami, Peyman
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Twumasi Afriyie, Ebenezer
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Norberg, Peter
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering. University of Gävle, Sweden.
    Gudmundsson, Kjartan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    A study of the thermal conductivity of granular silica materials for VIPs at different levels of gaseous pressure and external loads2014In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 85, p. 199-211Article in journal (Refereed)
    Abstract [en]

    Fast and reliable methods for the determination of thermal properties of core materials for vacuum insu-lation panels (VIPs) are needed. It is of great importance to know the thermal performance of a VIP core atdifferent levels of vacuum and external loads. In this study a new self-designed device, consisting of twocylindrical cavities connected to a Transient Plane Source instrument, is used to determine the thermalconductivity of low-density nanoporous silica powders, from atmospheric pressure down to 0.1 mbarwhile applying different levels of external pressure up to 4 bars. The study includes a brief theoreticaldiscussion of methods. The TPS is validated through comparison with available data for commercial silicaas well as through independent stationary measurements with a hot plate apparatus and with a TransientHot Bridge method. The different materials illustrate clear but different trends for the thermal conductiv-ity as a function of the level of vacuum and external pressure. The analysis of experimental results showsthat the transient methods are less suitable for measuring the thermal conductivity of low-density sil-ica powders, especially for the cases when the density is less than a limit at which the heat transfer byradiation becomes dominant compared to pure conduction.

  • 209.
    Karlsen, Lisa
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Amandusson, Frida
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Fastighetsutveckling av kulturmärkt byggnad2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I Gävle kommuns översiktsplan,

    Gävle stad 2025, finns en vision om att öka invånarantalet. För att detta ska vara möjligt krävs det ett stort tillskott av nya bostäder. Ett alternativ till att skapa nya bostäder är genom en funktionsändring av befintliga byggnader, vilket är ett alternativ som Gävle kommun ser positivt på.

    En fastighet som står inför en funktionsändring i syfte att exploatera Gävle är Norr 9:7. Fastigheten har ny ägare vars vision är att bygga om fastigheten till ett modernt och attraktivt bostadsområde. Fastigheten ligger centralt och används idag av Gefle Dagblad som kontorslokaler och tidningstryckeri.

    Den här rapporten redovisar fastighetsutvecklingen av den kulturmärkta byggnaden som finns inom fastigheten. Utifrån byggnadens förutsättningar, efterfrågan på bostadsmarknaden och de önskemål som ställts av den nya fastighetsägaren och kommunen har förslagshandlingar tagits fram. Förslagshandlingarna redovisar planlösningar för verksamhetslokaler och bostäder. Bostäderna är utformade att uppfylla tillgänglighetskraven som BBR ställer vid ombyggnad och funktionsändring.

    Rapporten redovisar också en ekonomisk analys som ger ett förslag på en rimlig hyresnivå för bostäderna.

    Då många avgränsning

  • 210.
    Karlsson, Jonathan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Jacobsson, Philip
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Mer bostadsarea med tunnare ytterväggar: En studie av dagens ytterväggar och dess inverkan på byggnadens ytanvändning2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 211.
    Karrbom Gustavsson, Tina
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    A story of a technical tourist2009In: Guiding and Guided Tours / [ed] Petra Adolfsson, Peter Dobers & Mikael Jonasson, Göteborg: BAS Publishers , 2009Chapter in book (Other academic)
  • 212.
    Karrbom Gustavsson, Tina
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Byggprojekt: Ett skapande kaos?2011In: Byggsektorns förmågor / [ed] Tina Karrbom Gustavsson, KTH Royal Institute of Technology, 2011Chapter in book (Other academic)
  • 213.
    Karrbom Gustavsson, Tina
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Liminality Roles in Construction Project Practice: Opportunities and Challenges2016In: Proceedings of the 32nd Annual ARCOM Conference: 5-7 September 2016, Manchester, UK, Association of Researchers in Construction Management / [ed] P W Chan and C J Neilson (Eds.), 2016, Vol. 2, p. 727-736Conference paper (Refereed)
    Abstract [en]

    Project management handbooks and courses teach structured and standardized ways of organizing and managing projects, including clearly defined project roles. However, projects are no isolated islands and projects in practice continuously develop and change. This is the case in, for example, the project based construction industry, and in which new inter organizational and collaborative work practices have become increasingly common. This paper is based on two case studies and explores developments and changes in construction project practice, in particular the development of new roles. The concept of liminality is used as analytical lens to better understand these new roles. Findings show new and challenging multi liminal roles that origin from other knowledge domains and professional communities of practice, than what is traditional in construction project management. This development poses both opportunities and challenges for the individual project worker and the development of construction industry practices.

  • 214.
    Karrbom Gustavsson, Tina
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Gohary, Hayar
    Borders and border crossing in construction projects2011Conference paper (Other academic)
  • 215.
    Karrbom Gustavsson, Tina
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Gohary, Hayar
    Akademiska Hus, KTH, Sweden.
    Boundary action in construction projects: new collaborative project practices2012In: International Journal of Managing Projects in Business/Emerald, ISSN 1753-8378, E-ISSN 1753-8386, Vol. 5, no 3, p. 364-376Article in journal (Refereed)
    Abstract [en]

    Purpose – Traditional construction project practice has been based on rigid and impermeable boundaries that have made communication, cooperation and integration a major challenge. However, new collaborative approaches have been developed. This paper aims at adding to knowledge on projects‐as‐practice by interpreting findings from a case study on a contemporary collaborative construction project. The purpose of this paper is to provide knowledge about organizational development in the project‐based construction industry by identifying boundary actions in contemporary collaborative construction practices.Design/methodology/approach – The paper is based on an exploratory longitudinal case study approach covering both early design phase and the following production phase, including interviews, participant observation at formal meetings and informal gatherings and internal and external documents. Thus, the methodology used is triangulation and the analysis has followed an interpretative process.Findings – The paper provides empirical insights into three examples of boundary actions of a collaborative construction project: stakeholder boundary action, professional boundary action and geographical boundary action. From a project‐as‐practice perspective, these boundary actions turn out to be interesting renewal initiatives, providing increased understanding of where and how renewal can take place.Research limitations/implications – The findings are based on a single case study and more research on this area is needed. However, the paper shows examples of boundary actions in a contemporary project and thus adds to the knowledge on contemporary projects‐as‐practice.Practical implications – The paper provides implications for construction project managers on examples of renewal arenas.Originality/value – The paper is exploratory and the findings are important for much needed development and renewal of the construction industry.

  • 216.
    Karrbom Gustavsson, Tina
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Hedborg Bengtsson, Susanna
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Eriksson, Per-Erik
    Luleå Tekniska Universitet.
    When you don’t have your own block: Horizontal supply chain integration in multi-project contextsIn: Article in journal (Refereed)
  • 217.
    Kassahun, Semunegus
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Rivethorne, Vincent
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Vägskador och sprickor på det statliga vägnätet: En förstudie om beläggningsskadors typ, omfattning och orsaker2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There is a great need for knowledge of what kind of damages on the road network that leads to

    maintenance services being carried out over a shorter and a longer period of time. An understanding

    for the causes is necessary to minimize the need of maintenance through right dimensioning of roads

    and optimized maintenance strategies. Damages on the road network are result of different factors

    such as traffic, climate, age of the road, age and traits of the pavement, drainage and the underlying

    layers. In majority, it is multiple damages combined with several causes for them that in the end leads

    up to maintenance services being carried out. The damages vary in different parts of the country as a

    result of difference in maintenance strategies and climate. On the other hand, the knowledge of the

    extent of the damages is very limited as the current follow up procedure on maintenance work is

    insufficient in regards of information and data collecting.

    To gain knowledge of the magnitude of damages and how they evolve over time there is need for

    measure methods that better reflects the occurrence of damages and not only secondary effects. Track

    is an example of a functional conditioned measure that may originate from several decomposition

    mechanics. Ideally measurements would provide information about the technical condition in various

    parts of the roadbed. If these surveys could prove the underlying causes to the deficiencies, there’s a

    better prerequisite to make the right decisions how to remediate the damages in question. Decisions

    that considers the possibilities to enhance drainage and to extend the lifetime of existing coating and to

    choose the right strategy for future remediates where time and place for more information of more

    extensive remediates is also considered.

    Hence the Swedish Department of transportation (Trafikverket) is conducting a pilot study where an

    extensive survey and analysis is being executed. The goal is to find the connection between road

    measurements with the damages that occurs on road to establish basis for enhanced maintenance

    planning efficiency. The goal of this thesis is to find the correlation of damages to perform

    maintenance measures, road types and the ground roads are built on. Through an extensive data

    collecting in the department’s computer software PMSv3 where all the road measures are gathered,

    these correlations will be discovered. Regarding the observations taken, this thesis is a foundation for

    continued study and research.

  • 218.
    Khachlouf, Rayen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Ahmed, Shakrin
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Massivträ och dess miljöpåverkan2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 219.
    Khalil, Faris
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Hanifi, Jonas
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Kommunikation vid ny- och ombyggantion av sjukhus: Förbättring av kommunikation vid ny- och ombyggnation av Danderyds sjukhus2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 220.
    Khoury, Petra
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Ali, Shyaw
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Val av FTX produkter i flerbostadshus för nyproduktion och ombyggnation2016Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 221.
    Kivinen, Jimmy
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Reth, Anton
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Effektivisering av byggproduktion med BIM: Jämförelse mellan en traditionell och modern arbetsmodell2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    I takt med att Sverige och dess befolkning ständigt ökar höjs trycket på byggsektorn. Situationen mynnar ut i att det nu ligger stor vikt i att man bygger effektivt och till så låg kostnad som möjligt. Det är därför vitalt att byggföretag hänger med i den tekniska utvecklingen på en marknad med ständigt ökande konkurrens.Examensarbetets innehåll bygger på befintliga studier inom ämnet samt ett samarbete med ett väletablerat byggföretag vars mål är att bygga och bevara bostäder för framtida generationer.Som ett resultat på detta examensarbete framkommer det fakta som indikerar att det i dagens byggindustri och dess byggprocess finns möjlighet till effektivitetsförbättringar samt miljardbelopp att spara vid en implementering av ett modernare och mer effektivt arbetssätt vid namn BIM – Building Information Modeling.

  • 222.
    Kjellsdotter, Line
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Tidsuppföljning2011Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In production at a construction site an important part during the projects is to manage time spent. Partly to be able to compare time spent against time according to budget/calculus but also to be able to regulate alternations, additional work and outgoing jobs by deciding its time spent.

    Within the framework of this thesis a utility shall be produced for this type of time management. This utility shall be produced as en Excel-file and shall be structured by references, formulas and conditional formatting. This file shall be able to be used in different kinds of projects and should be able to be fitted for the current project’s structure.

    The parts that this utility shall be able to act as a support to is time spent on alternations, additional work and outgoing jobs, payroll administration and total time spent on different working/materials.

  • 223.
    Krantz, Frida
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Building Information Modeling – In the production phase of civil works2012Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Building Information Modeling, abbreviated BIM, is a process of information sharing which enhances communication and which helps in visualizing complex problems in the building industry. BIM has not been used in a larger extent in the production phase of civil works. The purpose of the study is therefore to investigate driving forces behind the use of BIM and the resistors against it and to investigate in what ways BIM could be used in the production phase.The theoretical framework is based on one licentiate thesis, two degree projects, three research papers and three books. A qualitative method with semi-structured interviews was used. The interviews were made with a calculator, a supervisor and a CAD planner from Skanska, a constructor and project manager from ELU, a Project Information Officer from Tyréns and a VDC coordinator and VDC business developer from Veidekke who all have been working with BIM. This was to get a good representation from different actors and people with different professional roles.The study shows that the driving forces behind a use of BIM are that it enhances collaboration and communication between the actors, it makes it easier to visualize the project and the scope, and it provides a higher degree of accuracy of coordination’s. BIM also makes the work more effective and results in fewer errors. Above all, BIM give a possibility for a shorter production phase, shorter total project duration and a lower total cost. The study also shows that the resistors against the use of BIM are employee’s negative attitude against administrative work, that it is hard to measure profitability of using BIM, the uncertainty of who has the legal ownership of the data, and who has the responsibility of the accuracy of it. That the implementation cost and the design phase are more expensive is also a resistor against a use of BIM.BIM could be used in visualization with 3D models in collision controls and co-reviews in meetings, work preparations and at site. A workplace outline could also be printed from the 3D model to be placed on the site for visualization. 4D scheduling and 4D animations could be used for visualization in meetings, work preparations and at site. The study showed that quantity takeoff and cost estimation with 5D is only reconciled in the meetings in the production phase and that the programs for it are not needed in this phase. RFID tags could be used at site for logistics and tracking materials, and field verifications could be used to verify that a work task is executed according to exact coordination’s in the 3D model. Furthermore tablet computers could be used for bringing the technique of BIM to the site which enables a better understanding of complex work tasks for the workers. A BIM coordinator who understands the process of working with BIM and who could work as a bridge between the users and the technical development team is important in a successful implementation.The study also shows that the focus of BIM should lie on how to make use of the technique. The examples of how BIM could be used in the production phase of civil works have to be useful and meet the needs and demands of the users. The processes of using 3D models, 4D scheduling, 4D animations, RFID tags, field verifications and tablet computers should therefore be studied thoroughly to find how the technique could be applicable at site, in meetings and work preparations and how it could enhance the daily activities and work tasks. If the demands are met it will be accepted by both the user and the organization. Further research should therefore lie on how 3D models, 4D scheduling, 4D animations, RFID tags, field verifications and tablet computers could be useful in the production phase. These BIM techniques should then be tested on a real project to investigate how the processes could be useful at site, in meetings and in work preparations. Further research should also be made on how countries like Norway, Finland and USA have made use of BIM in the production of civil works.

  • 224.
    Kristjánsdóttir, Rut
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials.
    Design of Heavy DutyPavements2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This research is focused on design of Heavy Duty Pavement which is when a pavement loading exceeds highway levels. The environment where these conditions occur are for example at ports, industrial areas and airport because of the use of heavy vehicles as handling of containers by Straddle Carriers, Front Lift Trucks or Reach Stackers, airplanes and more. The main emphasis here will be on heavy duty pavements for ports. Different design methods are discussed and compared for the pavement design of ports. In this research two different design methods are thoroughly analyzed, the British Ports Associations Heavy Duty Pavements Manual which is a chart based procedure and the HIPAVE program which is an Australian Heavy Duty Pavement Design Guide. Both those methods are widely used around the world. Furthermore, an analysis is performed to research the plastic properties of the pavement. In most design methods, the material properties of the granular materials are assumed as elastic when they are not, they are elasto-plastic. A Finite Element Analysis is performed to determine if this assumption has significant effect on the design of pavements by comparing models of a design pavement section with elastic granular materials and elasto-plastic granular materials. The main conclusions from the comparison study of different pavement design methods are when using the HIPAVE program the total thickness of the design pavement section is smaller than using the British Ports Manual. Smaller thickness result in less materials needed for and therefor lower cost for the pavement section. Regarding the plasticity analysis, it is concluded that the assumption to model the behavior of unbound granular materials as elastic in pavement design is correct. The Finite Element Analysis determined that plasticity does have effect on the behavior of the materials with respect to elastic behavior, but there is not a considerable difference in pavement displacement between the two analysis.

  • 225. Kłos, R. A.
    et al.
    Wörman, Anders
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Hydraulic Engineering.
    Site specificity in advanced dose assessment modeling2015In: 15th International High-Level Radioactive Waste Management Conference 2015, IHLRWM 2015, American Nuclear Society, 2015, p. 447-454Conference paper (Refereed)
    Abstract [en]

    Final disposal of high-level radioactive waste is not straightforward. The aim is to isolate the waste from the biosphere over timescales that are long compared to recorded human history. Aside from the complex engineering requirement there is a highly sensitive legal requirement, embodied in the national regulatory framework relevant to the disposing organization, to provide a proportionately detailed assessment of the potential radiological impact of the disposal system on the health of future generations. Siting, construction and disposal is an iterative process. It starts with site selection, at early stages generic interpretations are appropriate. At later stages-e.g., construction licensing-the proponent must show a detailed understanding of the repository design, construction and potential radiological impact of any release to the human environment in the biosphere. Taking the example of the Swedish Nuclear Waste Management Company's 2011 license application for the construction of a spent fuel repository on the Baltic Coast of east-central Sweden, this paper looks at the role played by the incorporation of site-specific details in the dose assessment modeling that support the review of the license application. Implications of lessons learned in the Swedish context are extended to the international waste disposal community.

  • 226.
    Lacombe, Michelle
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Wijkström, Hugo
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Projektering av KL-trä: En jämförelsestudie av två flerfamiljshus i KL-trä2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Wood construction has its documented environmental benefits and Sweden is one of the world's largest wood products exporters. Despite this, Sweden has lagged behind in the construction of multi-family houses with wood construction. This reports starting point has been to investigate whether in the design phase of housing built with wood, there has been obstacles to large-scale construction. This report has compared two multi-family houses, the bulk of which consists of CLT. It has also set out to investigate how the two projects have chosen to solve fire and acoustics requirements. CLT is a cross-laminated solid wood element in three, five, seven or more layers that can be used as a material for building multi-family homes. The manufacturing process of CLT means that the elements are cross-glued which will prevent any future swelling and shrinkage of the material. When developing a relatively new material like CLT, a number of problems arise as knowledge and experience are inadequate. Two of the main problems in the design of CLT are the fire and acoustics requirements in Sweden, the report will review the requirements for regulations and how wood as material relies on these requirements. This report has led to a number of recommendations for CLT projectors. These recommendations are based on experiences from the two projects and the projectors associated with them. Important starting points for the design are the size of the span and that supporting elements are separated to avoid flange transmissions.

  • 227.
    Lagesson, Martin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Hägerstrand, Anton
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    FE-analys av sprickvidder i ung betong på grund av tvång2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Concrete is one of the most important and common building materials today. Concrete has very low tensile strength and because of this some amount of cracking is to be expected. Completely preventing cracking in concrete is complicated and costly. This report examines cracks in concrete caused by restraint. When the natural movement in a construction is restrained this will cause stress. This stress might lead to cracking. This report examines cracks that appear in concrete that has yet to reach its full tensile strength. The case that is being studied is that of a new wall that is cast on a slab that has reached full maturity. The report focuses on stresses that appear because of the heat production during hardening, as well as the drying that occurs after the cast is removed.

    For this purpose 3D models in the finite element software application Atena have been developed. These models simulate the heat and moisture development as well as the cooling that will occur during the hardening of the concrete. These models are also used to simulate the stress and cracking that will occur because of the relationship between the newly cast wall and the slab in place. Studies have previously been published based on this subject, but only in a 2D context where the shrinkage is applied as a boundary condition. A number of cases with varying boundary conditions have been compared in order to reach a crack pattern that corresponds to actual behavior.

    Reducing crack widths is important as they affect the strength as well as the lifetime of the concrete. The width of cracks that appear is even more important in constructions that need to be impermeable, for example water containers. Wide cracks are a cause of leakage, as well as reduced strength and longevity. The study looks at rules from Eurocode for designing impermeable structures. A template for calculating crack widths has been produced. This template is based on the Eurocode rule set. Since Eurocode is lacking any formulas to calculate heat development this has been done in the FE-software ConTeSt R&D, which is specifically designed to calculate heat development in a 2D section.

    The purpose of the study is to achieve a working model for the simulation of crack widths due to restraint. These results are to be compared to the results of the Eurocode calculations. The study shows that we are able to simulate an expected development in stresses and cracks, but does not result in a general model as the solution becomes specific to the case. As we have only achieved case specific solutions and no general method we have been unable to compare modelled results with manually calculated results.

  • 228.
    Lainio, Nellie
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Östanbäck, Christian
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Kalkylanalys av stambyten: En jämförelse av stambytesprojekt för att belysa viktiga parametrar vid initial kalkylering2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sweden’s real estate portfolio has a major renovation requirement. A large part of the renovations that need to be carried out are pipe replacement projects. These are major projects and not all housing associations are aware of the extent financial consequences it brings. Therefore, planning in the economy throughout the project are important. This thesis aims at seeing what affects a production estimate to differ from the actual final cost.ÅF infrastructure division thought that their calculations of the estimated cost for production too often differs to the actual final cost. At a first meeting with ÅF, it appeared that there has been discussion and thought for solutions to the problem for some time. The thesis is based on 3 issues that will provide answers on how to make a better production estimate.In order to answer the questions, project managers have been interviewed and literature has been studied. The assigned reference objects have been analyzed and compared in tables. This thesis has resulted in the insight of that the project managers at ÅF are relatively good at estimating the original cost of what the contractor produces for the pipe replacement projects. After the analysis, recommendations have been presented that can be developed and implemented in the ÅF approach to calculate their estimated cost of production even better. By calculating the costs that are not included in the original cost for the contractors in a more methodical manner, based on experience, the production cost can be optimized.The work has been going on for a limited time with delimitations and a selection of projects. The results presented in the report should be applied with caution and awareness about the differences in the projects.

  • 229.
    Lannestedt Edén, Sofia
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Nilsson, Alexander
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Överblivna installationsprodukter och byggmaterial: Finns det affärs- och miljömässig bärighet att samla in överbliver material från byggarbetsplatser2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, large amounts of fully functional materials are being thrown away within the construction industry of new buildings. This is a hidden problem, as the materials are not documented as leftover materials but in weight together with the other waste. The reason for disposal of materials is the pressure of time in the production; also, that there is no standard process to utilize the fully functional leftover materials when it occurs. Disposal of materials is considered to be easier, which requires less time and resources than by own initiative and commitment to take care of the materials. Recycling by reuse of materials is a huge gain for the environment. Production of materials accounts for the biggest environmental impact in the construction industry. By skipping the material manufacturing process, along with the managing and transportation that it entails, reduction of the environmental impact can be achieved. Recycling by reuse of materials and products implies that the manufacturing process can be avoided and the managing and transportation of materials would be reduced. In order to make reusing of leftover materials possible, a routine needs to be introduced at the companies and the different projects. This routine needs to be practically feasible and within reasonable financial limits.The purpose of this study is to investigate whether it is possible to establish a logistics centre where trading of fully functional material can be done. Environmental and economic aspects have been reviewed and compared with each other. Leftover materials and products will be gathered in a warehouse and then distributed for sale and reuse. A review of the costs and revenues that the logistics centre includes has been carried out in the form of a calculation. Interest and demand have been investigated as well. To motivate commitment to the reuse of materials, connections have been made between sustainable development, circular economics and environmental goals. The study has been carried out in cooperation with Skanska and is delimited to production of new residential buildings in the Stockholm area. The collected information is based on interviews and site visits. People that are involved in the production management of different projects have answered questions about their own experience regarding leftover materials, waste management, order and planning of materials, but also their own thoughts and opinions regarding potential solutions to the problem. Site visits have been carried out on a waste facility, various Skanska projects and a rental unit that Skanska itself operates. The answers from these interviews and the information from the site visits have been compiled and analysed.

  • 230.
    Larsson, Ebba
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Nordberg, Klas-Göran
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Luftkvalitet och sjukfrånvaro i förskolan2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Problem med smittspridning inom förskolan är idag en stor samhällskostnad, på grund av VAB-dagar, sjukdagar hos föräldrar och personal samt för vikarier. Smittspridningen och sjukfrånvaron är som störst under vinterhalvåret då olika typer av virusinfektioner såsom influensavirus florerar. Detta sammanfaller med perioden på året då den absoluta luftfuktigheten är som lägst utomhus.Genom att undersöka problematiken kring luftburen smitta var syftet med rapporten att kunna besvara två frågor. Vilka ventilationskrav bör ställas vid nybyggnation av förskolelokaler för att minimera smittspridningen? Och, hur kan luftkvaliteten förbättras i undersökta förskolebyggnader och på så sätt minska sjukfrånvaron?För att besvara den första frågeställningen genomfördes en litteraturstudie där information om luftburen smitta, luftflöde, luftföring och relativ luftfuktighet samlades in och analyserades. För att behandla den andra frågeställningen genomfördes fältstudier på fyra förskolor från SISABs fastighetsbestånd. Luftkvaliteten på de undersökta förskolorna utvärderades med temperatur-, koldioxid-, relativa luftfuktighets- och luftflödesmätningar. Därtill samlades information om förskolornas verksamhet och statistik över barnens sjukfrånvaro in.Efter genomförd litteraturstudie kunde några faktorer som påverkar kvaliteten på inomhusluften och dess förmåga att sprida en smitta observeras, och ett antal förslag på nya krav och rekommendationer kunde läggas fram. Det bör ställas ett krav på minst fyra omsättningar i förskolor, samt komplettera med ett minimikrav på antalet kvadratmeter per person i varje typ av rum. Därtill rekommenderas den omblandade ventilationsprincipen, med viss grad av riktad transport som enligt studien lämpade sig för verksamheten. Slutligen bör det rekommenderas att den relativa luftfuktigheten inomhus hålls inom intervallet 40-60%.De nya förslagen kunde till viss del intygas av resultatet från de genomförda fältstudierna, och ett antal rekommendationer för att förbättra luftkvaliteten på förskolorna kunde presenteras.På två av förskolorna kunde omsättningen ökas till 4 omsättningar i timmen vilket troligen medför större investerings- och driftkostnader. I en av förskolorna bör det undersökta rummet balanseras så att överluft ej tas ut i angränsande rum och sprider smitta vidare. För att höja RH på några av förskolorna föreslås att temperatur sänks och att i en av förskolorna eventuellt minska luftflödet för att inte vädra ut fukttillskottet. Därtill finns det möjligheter att förändra lokalernas invändiga ytor och därmed få det mer lättstädat och på så sätt minska antalet partiklar som kan vara smittbärande.

  • 231.
    Laurén, Sofia
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Dimensionering av betongkonstruktioner: En jämförande studie av BBK 04 och Eurokod 2 vid dimensionering av balkar och pelare2011Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, we use BKR and BBK 04 when designing concrete structures inSweden, which will, in the near future, be replaced by Eurocode 2. When you are designing buildings, you will use Eurocode 2 Part 1-1 and with this new standard, some new rules and general rules will be necessary to adopt. To examine how BKR and BBK 04 tells apart from Eurocode 2 when designing concrete structures, one beam and one column with often common dimensions, is studied. The beam is designed with consideration of (considerate to) durability at bending moments, shear forces and control of cracking. The column is designed with consideration of durability at eccentric axial load and bending moments in cross section on account of (due to) geometric imperfections.

     

    BBK 04 has gone one step closer to Eurocode 2 than earlier editions and the things that are different, when calculating reinforcement, is how they use the partial factors. BBK 04 reduce the values for characteristic strength of reinforcing steel and concrete but hardly increase the values for characteristic load while Eurocode hardly reduces the values for strengths but increases the values for loads more than BBK 04. Using Eurocodes recommended values, the amount of reinforcement is considerable higher than designing according to BBK 04. However, all members (countries) in European Union have a National Annex with their own chosen values and factors and with the Swedish values, both (regelverken) give almost the same amount reinforcement. Designing with Eurocode 2 and the Swedish values gives lower amount reinforcement in both beams and columns than designing with BBK 04, which has economical advantages.

     

  • 232.
    Le, Thanh-Nam
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Nonlinear dynamics of flexible structures using corotational beam elements2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The purpose of this thesis is to develop corotational beam elements for the nonlinear dynamic analyse of flexible beam structures. Whereas corotational beam elements in statics are well documented, the derivation of a corotational dynamic formulation is still an issue.

    In the first journal paper, an efficient dynamic corotational beam formulation is proposed for 2D analysis. The idea is to adopt the same corotational kinematic description in static and dynamic parts. The main novelty is to use cubic interpolations to derive both inertia terms and internal terms in order to capture correctly all inertia effects. This new formulation is compared with two classic formulations using constant Timoshenko and constant lumped mass matrices.

    In the second journal paper, several choices of parametrization and several time stepping methods are compared. To do so, four dynamic formulations are investigated. The corotational method is used to develop expressions of the internal terms, while the dynamic terms are formulated into a total Lagrangian context. Theoretical derivations as well as practical implementations are given in detail. Their numerical accuracy and computational efficiency are then compared. Moreover, four predictors and various possibilities to simplify the tangent inertia matrix are tested.

    In the third journal paper, a new consistent beam formulation is developed for 3D analysis. The novelty of the formulation lies in the use of the corotational framework to derive not only the internal force vector and the tangent stiffness matrix but also the inertia force vector and the tangent dynamic matrix. Cubic interpolations are adopted to formulate both inertia and internal local terms. In the derivation of the dynamic terms, an approximation for the local rotations is introduced and a concise expression for the global inertia force vector is obtained. Four numerical examples are considered to assess the performance of the new formulation against two other ones based on linear interpolations.

    Finally, in the fourth journal paper, the previous 3D corotational beam element is extended for the nonlinear dynamics of structures with thin-walled cross-section by introducing the warping deformations and the eccentricity of the shear center. This leads to additional terms in the expressions of the inertia force vector and the tangent dynamic matrix. The element has seven degrees of freedom at each node and cubic shape functions are used to interpolate local transversal displacements and axial rotations. The performance of the formulation is assessed through five examples and comparisons with Abaqus 3D-solid analyses.

  • 233.
    Le, Thanh-Nam
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges. Université Européenne de Bretagne, France.
    Battini, Jean-Marc
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Hjiaj, M.
    Université Européenne de Bretagne, France.
    Corotational formulation for nonlinear dynamics of beams with arbitrary thin-walled open cross-sections2014In: Computers & structures, ISSN 0045-7949, E-ISSN 1879-2243, Vol. 134, p. 112-127Article in journal (Refereed)
    Abstract [en]

    A new consistent corotational formulation for nonlinear dynamics of beams with arbitrary thin-walled cross-section is presented. The novelty is that the warping deformations and the eccentricity of the shear center are fully taken into account. Therefore, additional terms are introduced in the expressions of the inertia force vector and the tangent dynamic matrix. Their contribution is then investigated considering several numerical examples. Besides, the element has seven degrees of freedom at each node and cubic shape functions are used to interpolate local transverse displacements and axial rotations. The formulation's accuracy is assessed considering five examples with comparisons against 3D-solid solutions.

  • 234.
    Ledezma, Javier
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Mobilenhet för Akutintag: Förslag till konstruktion av ett fältsjukhus för akuta sjukvårdsinsatser2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 235.
    Lekander, Jon R. G. M.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Real estate portfolio construction for a multi-asset portfolio2015In: Journal of Property Investment & Finance, ISSN 1463-578X, E-ISSN 1470-2002, Vol. 33, no 6, p. 548-573Article in journal (Refereed)
    Abstract [en]

    Purpose – The purpose of this paper is to explore how tenant end demand dependence and investment market segmentation, as estimated through sector type, impacts real estate portfolio strategy in the context of the multi-asset portfolio. Design/methodology/approach – The analysis is performed for six investor domeciles, for domestic and international investments over several cycles. The analysis is performed in a mean variance framework. Findings – The findings are consistent with the hypothesis that an investor benefits from investing in real estate assets where end demand is dependent on local factors rather than global factors. Practical implications – The efficiency of the overall multi-asset portfolio benefits from a deeper understanding of how the real estate portfolio is constructed. Locally dependent real estate, i.e. real estate that is dependent on local economic factors, tends to better support the overall portfolio than do real estate that is dependent upon global factors. Originality/value – The paper contributes to the broader knowledge through extending earlier studies using similar methodology by extending the data series to cover the impact of the latest global financial crises, as well through extending the knowledge how the real estate portfolio should be constructed to better support the overall objectives of the multi-asset portfolio.

  • 236.
    Leyton, Israel
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Åtgärdsplan mot sättningsskador: En allmän jämförelse mellan pålning- och geopolymermetoden.2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    Demand for foundation reinforcement has increased significantly and is becoming more andmore common around the world. Today, there are several solutions for settlement damages,as well as the various factors that determine which one is most suitable. In Sweden, piling andconcrete reinforcement are the most common methods, but the use of geopolymer is alsobecoming increasingly popular action plan against settlement damages.The solution to settlement damage itself is to reinforce the soil on which the structure is built.The major problem is that the methods available for solving settlement problems today arecomplicated and expensive to perform.The geopolymer method is a technology based on injecting the geopolymer into the soil, whichis then responsible for reinforcing it by a swelling effect from it’s chemical reaction. Themethod is considered extremely efficient and with no major interference to the surroundingenviroment when repair occurs.This thesis deals with the effectiveness of the geopolymer technology in comparison to othertraditional basic reinforcement methods, such as piling. The comparison itself is more focusedon the economic and technical aspects of each method, with a slight insight into it’senvironmental impact.When we build more, it becomes more common to build on soil with poorer conditions, whichmeans that the development of reinforcement methods and ground stabilization becomesessential for future settlement problems.

  • 237.
    Liljare, Mattias
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Silveira Övrebö, Theodore
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Utveckling av betong för 3D-skrivare2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    3D printing, also known as additive manufacturing, is a manufacturing method that has revolutionized many industries and has grown widely both in industry and private use. The technique means using a layer-upon-layer method to manufacture different objects. With today's technology, it is possible to print objects of, for example, metal, plastic, concrete and several other materials. Additive manufacturing of concrete structures can be used to create new smart design solutions, which means significant material savings and reduced material waste. Production costs and time reduction may also be achieved using the method due to lower labor requirements and reduced costs for manufacturing and assembling of molds. This study contributes to an increased understanding of what is required to develop a functioning concrete material for additive manufacturing. In order for additive manufacturing to be standardized, become commercial and be broadly used, a deeper understanding of the concrete properties is required. This is because the material used in 3D printing differs from conventional concrete. The purpose of this project is to develop a concrete mixture adapted for additive manufacturing. A survey is made to find (i) a concrete mixture with suitable mechanical material properties, and (ii) a concrete mixture well adapted to 3D printers. The most important thing for a concrete mix to be used for additive production is that the mixture can be pumped through the system and extracted through the nozzle during manufacture and that the final material shows good buildability. Pumpability is a prerequisite for the concrete to be used in a 3D printer. The concrete must be sufficiently flexible to be pumped out through a nozzle, but also have a sufficiently good internal cohesion so as not to deform after it has been pumped out. Pumpability is largely affected by the type of pump system used. The results vary depending on the pump, nozzle and hose used in the material tests. It seems that a general mix adapted to several different pump systems is difficult to achieve. In this work, six different mixtures with different variations have been tested. This led to 38 mixtures that underwent various tests. The mixtures with the best results after fine adjustments were mix 4.1 and 5.1, they showed high quality for pumpability and buildability. Mixture 4.1 contains water, plant cement, starvis 3040, glenium, CERW, crush ballast and glass fibers and mixture 5.1 is similarly fixed with fly ash instead of CERW.

  • 238.
    Liljestrand, Mathias
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Ljungberg, Kirill
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Utveckling av betong för additiv tillverkning2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    3D writing of concrete has great potential for future building engeneering. Other industries such as the automotive industry, pharmaceutical industry, aerospace industry, etc. have already additive manufacturing methods for commercial purposes. The reason for this is the high standards set in the construction industry as well as difficulties to balance the demanded properties. At the additive manufacturing creates objects through that the matter be placed in the warehouse incrementally. The objects are first created digitally as a 3D object, which is then divided into horizontal layers. Then a 3D printer follows a pre-programmed path where it places the material until the object has reached its final form. . Despite the major challenges so for additive manufacturing methods in the construction industry, with potential benefits that outweigh the difficulties; complex designs for low cost, no material waste, fast build time, less labor, , less environmental degradation, etc. Conventional concrete is unusable when the concrete for additive manufacturing methods require properties that have not previously been demanded. It should be fluid enough for pumping but at the same time rigid enough for stacking. The concrete opening time is required to be constant in order to avoid that the concrete starts to harden before it is printing.

    The report intends to contribute to the development of concrete adapted for additive manufacturing methods in the construction industry. This is accomplished through the development and analysis of new types of concrete. There are no standard and proven methods for assessing concrete adapted for additive manufacturing methods. How the manufacturing method affects the environment is examined with the aim of reducing environmental impacts.

    A good concrete mix for additive manufacturing methods is based not only on its structural purpose, but also on the type of nozzle used. Because of this, it is currently impossible to create a universal mix that is adapted for all of the nozzles and the printer system. The concrete requires a high cement share which leads to higher carbon dioxide emissions, but the percentage of concrete required is lower due to no material play. Additives are used to lower the cement share and achieve a more cohesive concrete mixture. The final concrete mixtures have room for improvement. Further adjustments of vct, additives, reinforcement and chemical admixtures should be made for the development of concrete for additive manufacturing methods.

  • 239. Lim, E.
    et al.
    Ito, K.
    Sandberg, Mats
    KTH Research School University of Gävle, Sweden.
    Performance evaluation of contaminant removal and air quality control for local ventilation systems using the ventilation index Net Escape Velocity2014In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 79, p. 78-89Article in journal (Refereed)
    Abstract [en]

    A concept of ventilation efficiency, Net Escape Velocity (NEV), developed by authors presents the net and integrated velocity of contaminant transport by convection and diffusion effect at a point within the room. The NEV is the effective ventilation rate with a velocity scale determining the contaminant concentration at a target point and can be expressed by vector and scalar quantities. It is the most important characteristic of NEV concept. An expanded concept of NEV (NEV*), under an assumption that the inflow flux of a contaminant on the control volume is a contaminant generation, was proposed. We believe that the NEV and NEV* distributions can provide helpful information for ventilation design to control contaminants.The purpose of this study was to demonstrate the advantage and contribution of NEV* to current ventilation design procedure by using numerical analysis. Here, it was evaluated by the NEV* that the contaminant removal performances of local ventilation systems which are a kitchen exhaust hood in a kitchen environment, a push-pull hood in an industrial environment and an adsorptive building material in a test chamber. The distributions of the NEV* as vector quantities under the different flow and diffusion fields were analyzed to investigate contaminant leakage across the hypothetical boundaries of the control target domain of the local ventilation hood and to investigate the contaminant concentration reduction performance of the adsorptive building materials.

  • 240.
    Lin, Chang
    et al.
    Natl Chung Hsing Univ, Dept Civil Engn, Taichung 40227, Taiwan..
    Wong, Wei-Ying
    Natl Chung Hsing Univ, Dept Civil Engn, Taichung 40227, Taiwan..
    Kao, Ming-Jer
    Natl Chung Hsing Univ, Dept Civil Engn, Taichung 40227, Taiwan..
    Yang, James
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures. Älvkarleby Lab, Vattenfall AB Res & Dev, SE-81426 Älvkarleby, Sweden..
    Raikar, Rajkumar V.
    KLE Dr MS Sheshgiri Coll Engn & Technol, Dept Civil Engn, Angol Main Rd, Belgaum 590008, Karnataka, India..
    Yuan, Juan-Ming
    Providence Univ, Dept Data Sci & Big Data Analyt, Taichung 43301, Taiwan..
    Hydrodynamic Features of an Undular Bore Traveling on a 1:20 Sloping Beach2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 8, article id 1556Article in journal (Refereed)
    Abstract [en]

    The hydrodynamic characteristics, including local and convective accelerations as well as pressure gradient in the horizontal direction, of the external stream of an undular bore propagating on a 1:20 sloping beach are experimentally studied. A bore with the water depth ratio of 1.70 was generated downstream of a suddenly lifted gate. A high-speed particle image velocimetry was employed to measure the velocity fields during the run-up and run-down motions. The time series of free surface elevation and velocity field/profile of the generated bore, comprising a pure bore accompanied by a series of dispersive leading waves, are first demonstrated. Based on the fast Fourier transform (FFT) and inverse FFT (IFFT) techniques, the free surface elevation of leading waves and the counterpart of pure bore are acquired separately at a specified measuring section (SMS), together with the uniform horizontal velocity of the pure bore. The effect of leading-wave-induced velocity shift on the velocity profiles of the generated bore are then evaluated at the SMS. To understand the calculation procedure of accelerations and pressure gradient, three tabulated forms are provided as illustrative examples. Accordingly, the relationships among the partially depth-averaged values of the non-dimensional local acceleration, convective acceleration, total acceleration and pressure gradient of the generated/pure bore acquired at the SMS versus the non-dimensional time are elucidated. The trends in the non-dimensional accelerations and pressure gradient of the external stream of generated bore are compared with those of the pure bore. During the run-up motion from the instant of arrival of the bore front to the moment of the peak level at the SMS, continuous decrease in the onshore uniform horizontal velocity, and successive deceleration of the pure bore in the onshore direction are evidenced, exhibiting the pure bore under the adverse pressure gradient with decreasing magnitude. However, the pure bore once ridden by the leading waves is decelerated/accelerated spatially and accelerated/decelerated temporally in the onshore direction during the rising/descending free surface of each leading wave. This fact highlights the effect of pre-passing/post-passing of the leading wave crest on the velocity distribution of generated bore. It is also found that, although the leading waves have minor contribution on the power spectrum of the free surface elevation as compared with that of the pure bore, the leading waves do play an important role on the magnitudes of both accelerations and pressure gradient. The largest magnitude of the acceleration contributed by the leading waves is around 26 times the counterpart contributed by the pure bore. Further, during the run-down motion right after the moment for the peak level of the bore, a linear increase in the magnitude of the offshore uniform horizontal velocity and a constant local acceleration with increasing time are both identified. The partially depth-averaged value of the non-dimensional pressure gradient is equal to a small negative constant (-0.0115) in the offshore direction, indicating that the bore is subject to a constant favorable pressure gradient.

  • 241.
    Lindblad, Hannah
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Värdet med en certifiering i Miljöbyggnad: Ur fastighetsägarens och hyresgästens synpunkt2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 242.
    Lindblad, Hannes
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    BIM in Translation: Exploring Client Organisations as Drivers for Change in Construction2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    New technology is constantly being developed, presenting new opportunities and enabling innovative solutions to both known and unknown problems. Most industries place a large amount of trust in the opportunities offered by digitalisation. Information technology is being developed to enable new work practices and thereby drive change. However, the use of technology often drifts away from the developer’s intentions when it is introduced into an organisational setting. The management of such technology implementations is thus complex, both in terms of the technology itself and the organisational context in which it is implemented.

    In the architectural, engineering and construction (AEC) industry, the technology ‘Building Information Modelling’ (BIM) is currently being introduced. This industry is often described as fragmented, having low productivity and being reluctant to innovate. BIM is presented as new paradigm for this industry, as it is able to drive change towards inter-organisational collaboration, increase overall quality, and simultaneously lower costs. The industry has, however, been tentative towards BIM and widespread implementation has not yet taken place. To influence the industry towards adopting this new technology, public client organisations have been argued to play a vital role as innovation champions, demanding BIM-use through procurement. Still, there is a lack of studies exploring such implementation initiatives from the client perspective.

    In this thesis, the case of BIM implementation at the largest infrastructure client in Sweden is presented. This case shows how the client has undertaken an implementation process to both benefit its own organisation and increase productivity and innovation within the whole infrastructure branch of the AEC industry. With the purpose of problematising and contributing with reflective perspectives on the role of client organisations as drivers for industry change by implementation of information technology, the BIM implementation at this organisation is viewed as an empirical example of how information technology is introduced to influence an inter-organisational network of actors and establish change. 

    The case is analysed from the perspective of an analytical framework, taking inspiration from actor-network theory and sociology of translation. Thus, the implementation is viewed as a process of translation, where key actors are identified and enrolled into using BIM. Viewing BIM implementation as a translation reveals a complex network of actors linked to the implementation in question. The implementation is developed as a sequential translation, where project managers are intended to act as delegates, demanding and promoting BIM in their projects.

    This thesis problematises the role of client organisations in initiating change through the implementation of technology. Enrolling actors into using BIM has, in the studied case, primarily been done by the development of new demand documents. This strategy has, however, been problematic as the demands have not been accepted as intended. Instead, the results of this thesis argue for the importance of client organisations as negotiators, and that they are not only needed to establish demand for new technology.

  • 243.
    Lindblad, Hannes
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Black Boxing BIM: The public client’s strategy in BIM implementation2019In: Construction Management and Economics, ISSN 0144-6193, E-ISSN 1466-433X, Vol. 37, no 1, p. 1-12Article in journal (Refereed)
    Abstract [en]

    Building information modelling (BIM) is widely discussed in both industry and academia and studies have argued that public clients play an important role in industry’s implementation of BIM. While public client initiatives have gained much interest in previous research, there is still a lack of knowledge exploring the public clients’ role and choice of strategies when implementing BIM with the aim to change industry. Based on a case study of BIM implementation at the largest infrastructure client in Sweden, this paper applies the theory sociology of translation to explore the role of the public client as a driver for industry change and the strategy used during this process. The case study shows how the public client tries to influence its own organization and the construction industry as a whole. Findings show that the main strategy for enrolling actors to implement BIM is to demand its use in the procurement of all construction projects, thereby attempting to establish the BIM issue as a Black Box. A Black Box, a locked network element, which includes associated inscriptions aimed at prescribing BIM use in projects conducted by this client. The acceptance of this Black Box has however been problematic, resulting in a diverse influence on the demand for BIM in procured construction projects.

  • 244.
    Lindblad, Hannes
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Lost in Translation: A case of BIM implementation at a large public client2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The technology of Building Information Modelling (BIM) is being introduced to the Architectural, Engineering and Construction (AEC) industry. This industry is generally perceived as being fragmented, having low productivity and with a low rate of innovation. BIM is presented as new paradigm within this industry, enabling inter-organisational collaboration, overall increasing quality while simultaneously lowering costs. But widespread BIM implementation has not yet taken place. In order to increase adoption, public client organisations have been argued to be the actors needed to initiate and drive the implementation of BIM. However, the client perspective of such implementation initiatives has not been the main focus of earlier research.

    In this licentiate thesis the BIM implementation process conducted by the largest infrastructure client in Sweden is analysed. This organisation implements BIM both to benefit their own organisation but also to increase productivity and innovation within the whole infrastructure branch of the AEC-industry. With the purpose of increasing the understanding of technology driven change processes at public client organisations, the BIM implementation at this organisation is analysed as an empirical example. 

    The case study is analysed by a theoretical framework taking inspiration from Actor-Network theory and Sociology of Translation. Based on this analysis the translation process, where key actors are identified and enrolled into using BIM are described. The analysis reveals a complex network of actors linked to the implementation in question. Instead of a single BIM concept, several different and sometimes conflicting interpretations of BIM are simultaneously being translated.

    This licentiate thesis problematizes the role of client organisations in initiating change within a network of actors. The main ways of enrolling actors into using BIM have in the studied case been the development of new demand documents. This strategy has however been problematic as the new demands for BIM have not been accepted as intended within many construction projects. Instead, the results of this thesis argue for the importance of client organisations as negotiators, not only needed to establish demand for a new innovation.

  • 245.
    Lindblad, Hannes
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Organising the Implementation of BIM: A study of a large Swedish client organisation2016In: Building up business operations and theirlogic: Shaping materials and technologies / [ed] Arto Saari, Pekka Huovinen, 2016, Vol. 3, p. 356-367Conference paper (Refereed)
    Abstract [en]

    Building information modelling (BIM) is currently much discussed in the construction industry.It has been brought forward as a way to address the problems with slow increase in productivityperceived in the industry. To support and drive the industrywide implementation of BIM, manylarge public client organisations are currently in the process of implementing BIM. The purposeof this paper is to explore how a large client organization organises their BIM implementation.In order to reach this objective a case study of the BIM implementation process at the largestpublic infrastructure client in Sweden has been conducted. This case study is supplementedwith interviews with the management of the implementation project together with interviewswith project managers in pilot projects implementing BIM. Based on the results of this study, ithas been found that the BIM implementation is mainly focused on the technical requirements tosupport the shift from traditional drawings, to object oriented information. How this shifttowards object oriented information will influence changes to work practices is however notdefined within this implementation project.

  • 246.
    Lindblad, Hannes
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Gustavsson, Tina Karrbom
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Receptiveness for change: The case of a public client2017In: Association of Researchers in Construction Management, ARCOM - 33rd Annual Conference 2017, Proceeding, Association of Researchers in Construction Management (ARCOM), 2017, p. 64-72Conference paper (Refereed)
    Abstract [en]

    The construction industry needs to change to meet the needs for a more sustainable built environment. For industry change to happen, public clients have been suggested to play a key role as change agents because of their power to state requirements when procuring, and due to their role as long-term property owner. This makes receptiveness for change within public client organizations a vital issue for industry change. The aim of this paper is to explore receptiveness for change at a public client organisation by applying the framework of receptive contexts developed by Pettigrew et al., (1994). Based on an empirical case study of a public client's implementation of Building Information Modelling (BIM) during the period between 2013 and 2017, findings indicate that there is a lack of a receptive context, which hamper the public client's ability to take on the role as change agent and drive industry change. The conclusion is that the idea of public client's as change agents also comes with challenges and that there is a need for more studies on how to develop receptiveness in large public organizations.

  • 247.
    Lindblad, Hannes
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Karrbom Gustavsson, Tina
    Public Clients as Drivers for Change: Exploring BIM implementation, Systems Integrators and Relative BoundednessIn: Construction Management and Economics, ISSN 0144-6193, E-ISSN 1466-433XArticle in journal (Refereed)
    Abstract [en]

    Public client organizations are suggested as drivers for change and innovation towards a more sustainable, efficient and productive construction industry. It is argued that clients have power and are in a position to act as ‘innovation supporters’ or ‘change agents’. However, clients’ role and ability in driving change is underexplored and in need further investigation. The purpose here is to further explore public clients’ ability in driving construction industry change. We do this by investigating a change initiative – the implementation of BIM – at a large public infrastructure client. Receptiveness for change is used as framework and the analysis is based on combining literature on systemic innovation and the role of systems integrators together with the phenomena of relative boundedness.Findings show that client driven change by systemic innovation is challenging because of relative boundedness and that client driven change in relatively unbounded contexts requires a two-stage process. By combining the concept of systems integrators with the concept of relative boundedness we contribute to the understanding of challenges with client driven change in construction. Findings are relevant for research on the project managers’ role as systems integrators in BIM implementation, for public project governance and, in particular, for procurement.

  • 248.
    Lindblad, Hannes
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Project Communication.
    Rudolphsson Guerrero, Jacob
    Client’s Procurement Policies for Promoting BIM Implementation and Innovation in ConstructionIn: Article in journal (Refereed)
    Abstract [en]

    The construction industry is often described as a fragmented, loosely coupled industry, slow to innovate and lacking in productivity. In order to address these issues, client organizations are commonly acknowledged as key actors for change. However, what this role constitutes of is less clear, for example, questions arise such as: should innovation be mainly supplier-led or client-led? The aim in this paper is to explore different strategies clients can adapt in the promotion of innovation in the construction industry. To achieve the purpose, a case study has been conducted of the largest infrastructure client in Sweden; exploring two strategies which is simultaneously deployed to stimulate innovation. The studied organization is on one hand trying to influence the industry to implement Building Information Modelling (BIM), adopting a BIM policy and actively influencing the supply chain, while on the other hand stimulate innovation through providing more flexibility in projects, enabling suppliers to propose new solutions and emphasising market competition. Although the strategies essentially deal with different types of innovation, either a known or unknown innovation; the research finds that simultaneous use of these strategies creates intra-organizational tensions within the client organization. The findings provide insights in different strategies clients can use in order to stimulate innovation and contribute to understanding of client organization’s role in stimulating innovation in the construction industry.

  • 249.
    Lindman, Markus
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Gustafsson Magnusson, Martin
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Dynamiska egenskaper hos håldäcksbjälklag: En jämförelse mellan uppmätta egenskaper och analytiskt beräknande2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 250.
    Lindmark, Jakob
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Medlöv, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Analys av Kv. Släggan med gestaltningsförslag: Innehållande konstruktionslösningar, energiberäkningar, volymstudier och förbättringsåtgärder2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
2345678 201 - 250 of 420
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