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  • 1.
    Aalto, Jonatan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Neuman, Elisabeth
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Comparison of Punching Shear Design Provisions for Flat Slabs2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Abstract

    A new generation of EN 1992-1-1 (2004) also known as Eurocode 2 is under development

    and currently there is a set of proposed provisions regarding section 6.4

    about punching shear, PT1prEN 1992-1-1(2017). It was of interest to compare the

    proposal with the current punching shear design provisions.

    The aim of this master thesis was to compare the punching shear resistance obtained

    in accordance with both design codes. Furthermore the eect of some parameters

    on the resistance was to be compared. It was also of interest to evaluate the userfriendliness

    of the proposal.

    In order to meet the aim, a case study of a real  at slab with drop panels was performed

    together with a parametric study of a pure ctive  at slab. The parametric

    study was performed for inner, edge and corner columns in the cases prestressed,

    without and with shear reinforcement.

    It was concluded that the distance

    av from the column axis to the contra  exural

    location has a big in uence on the punching shear resistance. The factor

    ddg

    considering concrete type and aggregate properties also has a big impact on the resistance.

    The simplied estimation of

    av according to 6.4.3(2) in PT1prEN 1992-1-1

    (2017) may be inaccurate in some cases.

    The length

    b0 of the control perimeter has a larger eect on the resistance in EN

    1992-1-1 (2004) than in PT1prEN 1992-1-1 (2017).

    In PT1prEN 1992-1-1 (2017), studs located outside the second row has no impact

    on the resistance.

    The tensioning force in a prestressed  at slab has a larger in uence on the resistance

    in PT1prEN 1992-1-1 (2017) than in EN 1992-1-1 (2004). Furthermore,

    the reinforcement ratio is increased by the tendons, and thus aect the resistance in

    PT1prEN 1992-1-1 (2017).

    Clearer provisions for the denition of the support strip

    bs for corners and ends

    of walls are needed in PT1prEN 1992-1-1 (2017).

    It may be questionable if the reduction of the perimeter for a large supported area in

    accordance with 6.4.2(4) in PT1prEN 1992-1-1 (2017) underestimates the resistance

    v

    in some cases.

    Considering the work-load with PT1prEN 1992-1-1 (2017), more parameters are

    included. However, they may not require that much eort to obtain.

    Keywords: Punching shear, resistance, concrete,  at slab, design provisions, Eurocode

    2, case study, parametric study, shear reinforcement, prestressed

    vi

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  • 2.
    Aamodt, Edvard
    et al.
    RISE Research Institutes of Sweden, Safety and Transport, Fire and Safety.
    Holmvaag, Ole Anders
    RISE Research Institutes of Sweden, Safety and Transport, Fire and Safety.
    Sanfeliu Melia, Cristina
    RISE Research Institutes of Sweden, Safety and Transport, Fire and Safety.
    Erfaringer med mobile vanntåkeanlegg installert i boliger2022Report (Other academic)
    Abstract [en]

    Experiences regarding personal protection water mist systems installed in dwellings. Personal protection water mist systems can produce a water mist that can cool down and limit a fire in a small area in a dwelling. The system is equipped with sensitive detectors which can activate the system in the early stages of the fire and limit the fire spread, and in some cases extinguish the fire. This gives more time for evacuation, which can be especially important for vulnerable people with risk factors, like impaired cognitive and physical functioning. The goal of this study has been to map the experiences in Norway regarding personal protection water mist systems, considering how the municipalities have experienced the work related to the systems and whether the systems have activated and saved lives. This will shed light upon whether mobile water mist systems are appropriate measures for vulnerable people in the society, and the risk factors that determine whether the measure is appropriate or not. This study has used literature studies, questionnaires, and interviews to map the experiences of personal protection water mist systems in Norway. The results showed that personal protection water mist systems installed in Norwegian dwellings have been activated in connection with fire outbreaks, and thus limited or extinguished the fire. This has saved lives on several occasions and reduced the damage potential. There are many people who have risk factors that make it appropriate to install a mobile water mist system in their home, but there are also exceptions. The risk factors that indicate that it is beneficial to install mobile water mist systems in Norwegian dwellings are - Impaired cognitive abilities - Impaired physical abilities - Drug and alcohol problems - Smoking - Living alone The systems are particularly suitable when several of the risk factors are present at the same time. It was also shown that personal protection water mist systems are not suitable for mobile people who spend time in several places in the home and are therefore often outside the system's coverage area. Personal protection water mist systems are not recommended for people who may have the potential to sabotage the system. In questionnaires and interviews, it emerged that there are big differences between how Norwegian municipalities work with assigning, installing, operating, and maintaining personal protection water mist systems. In larger municipalities, there are more people who rely on routines and formal processes for the work, and there is therefore a greater proportion of the larger municipalities who distribute the facilities out to individuals than in the small municipalities where the work is more characterised by informal routines and personal relations. 3 Based on the results from this study, it is our opinion that the following aspects should be covered by future work: • Need for a new and updated cost-benefit analysis for personal protection water mist systems. • Need for a better statistical basis for assessment of the personal protection water mist systems. • Need for a Norwegian test standard for personal protection water mist systems. • Need for clear guidelines for assignment, procurement, installing, operation, and maintenance of personal protection water mist systems.

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  • 3.
    Aamodt, Edvard
    et al.
    RISE Research Institutes of Sweden, Safety and Transport, Fire Technology.
    Rønning, Birger
    RISE Research Institutes of Sweden, Safety and Transport, Fire Technology.
    Sikkerhetsbehov for kullgriller i restauranter2020Report (Other academic)
    Abstract [en]

    The RISE report 2019:04 «Charcoal and wood burning ovens in restaurants – Fire safety and documentation requirements» [1] investigated regulations and documental demands tied to charcoal and wood burning ovens in restaurants in Norway. A part of the conclusion in this report emphasized the need for, through physical testing, mapping whether existing test standards covers the safety requirements of charcoal ovens in restaurants. NS-EN 13240:2001 «Roomheaters fired with solid fuel. Requirements and test methods» [2] was chosen as a relevant test standard. Three test ovens (a closed test oven, a dummy oven and an open test oven) was produced at RISE Fire Research. Their construction with regard to insulation capabilities, materials and dimensions was based on existing charcoal ovens placed on the Norwegian marked. This was done to achieve an objective depiction of the issue, without the need for a specific brand of ovens. Restaurant oven charcoal was utilized to achieve as real heat development as possible in the test ovens. The test layout is based on NS-EN 12340:2001, with a test rigg constructed of two «safety walls», ceiling and floor attached with thermocouples. Temperatures from the test oven are registered in the safety walls at several positions according to a standardised grid, and in the ceiling and the floor each have one single measurement position measuring warmest point. Thermocouples in the chimney and exhaust duct measured the flue gas temperatures transported to the exhaust system. Four different tests were conducted, where the first one was a standardized safety test including the closed oven model. The second test was the same safety test setup with the dummy oven besides the closed oven. The dummy contained a built-in propane burner to simulate the heat load from a real oven. The purpose was to simulate two ovens placed next to each other. The third test was an overload test on the closed test oven with 150 % fuel load and higher refuelling frequency. The last test was a test of the open test oven. The safety test method described in NS-EN 13240:2001 is suitable to test the level of stable maximal temperature in the surrounding combustible materials, in the same way as for roomheaters, which the method is designed for. The method addresses safety aspects such as surface temperatures and handles on the oven. Tests show that the temperatures developed in the ovens have the potential to breech the temperature criterion given by the test standard, and therefore contribute to the ignition of surrounding combustible materials. Such situations pose a fire risk and safety measures regarding this aspect must be documented by the producer. NS-EN13240:2001 does not cover temperatures for exhaust duct and the production of sparks and their possible spread to combustible materials. These are important safety aspects which must be addressed when documenting the fire safety of restaurant grills. Tests show that sparks are created in the oven, including from restaurant charcoal fuel, and are transported into the exhaust duct, and out through the opening of the grill door. Together with high flue gas temperatures in the exhaust duct and deposits of soot and cooking oil this pose a fire risk. Documentation must therefore be presented, showing that the oven is equipped with measures (for instance spark screen) which guards the exhaust duct from sparks to a satisfactory degree. Operators of the oven must receive adequate training and must operate the closed oven with caution, as to avoid incidents with sparks being released though the door. The placement of ovens next to each other does not seem to increase the heat load on surrounding walls but may lead to increased temperatures in between the ovens. The consequences of temperature increases must be documented. Tests show that overloading with fuel and intensifying the refuelling intervals can lead to increased temperatures in the oven, which can affect materials and welding seams. Overloading can also affect the temperatures towards surrounding walls and exhaust ducts and therefore may affect fire safety negatively. NS-EN 13240:2001 requires the producer to documents how the oven is constructed and of what materials, and that the welding seams are dimensioned for the materials used. It is recommended that the producer documents the safety level of the oven materials with an overload test. It must also be documented that the exhaust ducts in which the flue gas are transported are constructed to handle the potential temperatures that can arise, including erroneous use.

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  • 4.
    Aamodt, Edvard
    et al.
    RISE Research Institutes of Sweden, Safety and Transport, Fire and Safety.
    Steen-Hansen, Anne
    RISE Research Institutes of Sweden, Safety and Transport, Fire and Safety. NTNU, Norway.
    Holmvaag, Ole Anders
    RISE Research Institutes of Sweden, Safety and Transport, Fire and Safety.
    LEARNING FROM FIRE INCIDENTS : Analysis of a devastating fire in a building with municipal housing in Norway2022In: Proceedings of the 32nd European Safety and Reliability Conference (ESREL 2022), 2022, p. 1156-Conference paper (Refereed)
    Abstract [en]

    This article presents an analysis of a fire in a municipal apartment building used as housing for people with challenges connected to drug addiction. The fire took place in Norway 7th of August 2021. The incident happened during the night and the fire was spreading quickly and intensely via the external wooden balconies. The combination of risk factors both connected to the fire development and the characteristics of the occupants raises the potential for fire fatalities. This analysis seeks to understand why the fire spread with such a speed, and how everyone in the building survived without injuries. The analysis identified both technical and human factors that may help to answer these questions. The findings suggest that there were deficiencies connected to the technical fire safety design that if improved could have reduced the fire damage. Factors promoting the fire spread and fire intensity include the choice of wood material used in the construction of the balconies, no sprinkler system installed on the balconies and a large fire load on the balconies caused by the occupants’ tendency to accumulate possessions on the balconies. Factors contributing to the outcome of no injuries or fatalities included occupants being awake during these late hours, and the strong social network between them. Such a network should be seen as a positive factor regarding robustness against fire and should be encouraged.

  • 5.
    Aarts, Mariëlle P. J.
    et al.
    Building Physics and Services, Department of the Built Environment, Eindhoven University of Technology, Eindhoven, the Netherlands.
    Aries, Myriam
    Jönköping University, School of Engineering, JTH, Civil Engineeering and Lighting Science. Jönköping University, School of Engineering, JTH. Research area Built Environment. Building Physics and Services, Department of the Built Environment, Eindhoven University of Technology, Eindhoven, the Netherlands.
    Diakoumis, Adonia
    Building Physics and Services, Department of the Built Environment, Eindhoven University of Technology, Eindhoven, the Netherlands.
    van Hoof, Joost
    Fontys EGT—Centre for Healthcare and Technology, Fontys University of Applied Sciences, Eindhoven, the Netherlands.
    Shedding a light on phototherapy studies with people having dementia: A critical review of the methodology from a light perspective2016In: American Journal of Alzheimer’s Disease and Other Dementia, ISSN 1533-3175, E-ISSN 1938-2731, Vol. 31, no 7, p. 551-563Article in journal (Refereed)
    Abstract [en]

    Light therapy is applied to older people with dementia as a treatment to reset the biological clock, to improve the cognitive functioning, and to reduce behavioral symptoms. Although the methodological quality of light therapy studies is essential, many aspects concerning the description of the lighting applied are missing. This study reviewed light therapy studies concerning the effects on people with dementia as a way to check the methodological quality of the description of light from a light engineering perspective. Twelve studies meeting the inclusion criteria were chosen for further analysis. Each study was scored on a list of aspects relevant to a proper description of lighting aspects. The overview demonstrates that the overall quality of the methodologies is poor. The studies describe the lighting insufficiently and not in the correct metrics. The robustness of light therapy studies can be improved by involving a light engineer or specialist.

  • 6.
    Aarts, Mariëlle P. J.
    et al.
    Department of the Built Environment, Eindhoven University of Technology, Eindhoven, Netherlands.
    Aries, Myriam
    Jönköping University, School of Engineering, JTH, Civil Engineeering and Lighting Science. Department of the Built Environment, Eindhoven University of Technology, Eindhoven, Netherlands.
    Straathof, Jochem
    Department of the Built Environment, Eindhoven University of Technology, Eindhoven, Netherlands.
    van Hoof, Joost
    Centre for Healthcare and Technology, Fontys University of Applied Sciences, Eindhoven, Netherlands.
    Dynamic lighting systems in psychogeriatric care facilities in the Netherlands: A quantitative and qualitative analysis of stakeholders’ responses and applied technology2015In: Indoor + Built Environment, ISSN 1420-326X, E-ISSN 1423-0070, Vol. 24, no 5, p. 617-630Article in journal (Refereed)
    Abstract [en]

    Long-term care facilities are currently installing dynamic lighting systems with the aim to improve the well-being and behaviour of residents with dementia. The aim of this study was to investigate the implementation of dynamic lighting systems from the perspective of stakeholders and the performance of the technology. Therefore, a questionnaire survey was conducted with the management and care professionals of six care facilities. Moreover, light measurements were conducted in order to describe the exposure of residents to lighting. The results showed that the main reason for purchasing dynamic lighting systems lied in the assumption that the well-being and day/night rhythmicity of residents could be improved. The majority of care professionals were not aware of the reasons why dynamic lighting systems were installed. Despite positive subjective ratings of the dynamic lighting systems, no data were collected by the organizations to evaluate the effectiveness of the lighting. Although the care professionals stated that they did not see any large positive effects of the dynamic lighting systems on the residents and their own work situation, the majority appreciated the dynamic lighting systems more than the old situation. The light values measured in the care facilities did not exceed the minimum threshold values reported in the literature. Therefore, it seems illogical that the dynamic lighting systems installed in the researched care facilities will have any positive health effects.

  • 7.
    Aarts, Mariëlle P.J.
    et al.
    Eindhoven University of Technology, Eindhoven, The Netherlands.
    van Duijnhoven, Juliëtte
    Eindhoven University of Technology, Eindhoven, The Netherlands.
    Aries, Myriam B. C.
    Jönköping University, School of Engineering, JTH, Civil Engineeering and Lighting Science. Eindhoven University of Technology, Eindhoven, The Netherlands.
    Rosemann, Alexander L.P.
    Eindhoven University of Technology, Eindhoven, The Netherlands.
    Performance of personally worn dosimeters to study non-image forming effects of light: Assessment methods2017In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 117, p. 60-72Article in journal (Refereed)
    Abstract [en]

    When determining the effects of light on human beings, it is essential to correctly measure the effects, and to correctly measure the adequate properties of light. Therefore, it is important to know what is being measured and know the quality of the measurement devices. This paper describes simple methods for identifying three quality indices; the directional response index, the linearity index and the temperature index. These indices are also checked for several commonly used portable light measurement devices. The results stresses what was already assumed, the quality and the outcome of these devices under different circumstances were very different. Also, the location were these devices are normally worn has an impact on the results. The deviation range between worn vertically at eye level and the wrist is between 11% (outdoor) to 27% (indoor). The smallest deviation, both in indoor and outdoor, was found when the device was placed on the sides of the eye (7%). 

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  • 8.
    Abbas, Ibrahim
    et al.
    Jönköping University, School of Engineering, JTH, Civil Engineering and Lighting Science.
    Thurann, Alexander
    Jönköping University, School of Engineering, JTH, Civil Engineering and Lighting Science.
    Implementering av Aerogel-matta vid köldbryggor2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
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  • 9.
    Abbas, Qaalid
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Hussein, Abdiwahab
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Studie om framtagning av montageplaner: En granskning av monteringsprocessen för prefabricerat byggande2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Dagens industrier anpassar numera sin tillverkning för att kunna massproducera och dra ner på personal och kostnader. Detta innebär ökad automatisering med större och kraftigare maskiner, utrustning och verktyg. För att garantera säkerheten på arbetsplatsen är det därför viktigt att rätt skyddsanordning och myndighetskrav följs och används. I byggbranschen ställer arbetsmiljöverket krav på branschföretagen gällande arbetsmiljö och särskilda underlag för produktionsarbetet. Denna studie undersöker montageplanen som används vid industriellt byggande som innebär användning av tunga, prefabricerade, element vid husbyggnad.

    Syftet är att studera hur en montageplan planeras, upprättas och implementeras. Studien utförs på uppdrag av In3prenör och omfattar 10 veckors arbete. Författarna har tillhandahållits information kring montageplanen för två projekt som studerats jämsides. Det ena, ett pågående projekt, är Allégården som är ett ROT-projekt av ett vård- och omsorgsboende och det andra, projekt Arlanda, är en nybyggnation av en servicebyggnad. Metoder som använts för att uppnå resultatet har varit en kombination av litteraturstudier, granskning av montageplaner, platsbesök och intervjuer.

    Resultatet visar på att otydliga riktlinjer kring vad som ska inkluderas i montageplanen är det största skälet till att det blir fel på arbetsplatsen. Det har även från intervjuerna påpekats att på grund av den tidspressade situationen och målbilden att undgå förseningar kan det ske misstag som kan få allvarliga konsekvenser. För att förbättra kvaliteten i montageplanerna måste riktlinjer från arbetsmiljöverket och boverket bli tydligare gällande montageplanens innehåll. Det är också viktigt att kritiska moment som kan medföra ökade risker framgår i montageplanen, vidare kan montörer utbildas för att öka deras riskmedvetenhet.

  • 10.
    Abbu, Muthanna
    et al.
    Building and Construction Engineering Deptartment, Northern Technical University, Mosul, Iraq.
    Al-Attar, Alyaa A.
    Building and Construction Engineering Deptartment, Northern Technical University, Mosul, Iraq.
    Abd Alrahman, Saad
    Building and Construction Engineering Deptartment, Northern Technical University, Mosul, Iraq.
    Al-Gburi, Majid
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    The mechanical properties of lightweight (volcanic pumice) concrete containing fibers with exposure to high temperatures2023In: Journal of the Mechanical Behavior of Materials, ISSN 2191-0243, Vol. 32, no 1, article id 20220249Article in journal (Refereed)
    Abstract [en]

    Fires are considered one of the main risks leading to building collapse. Lightweight concrete comprises a variety of components, each of which has a distinct behavior under the effect of temperature change. A total of sixteen concrete mixtures were investigated in this paper. A reference mix of concrete comprising simply ordinary Portland cement and ten mixes having varying percentages of fine and coarse lightweight aggregates (pumice), which were replaced gravel and sand by fine pumice and coarse aggregates pumice by 20%, 40%, 60%, 80%, and 100%, respectively. In addition, the study focused on the effects of adding fibers to lightweight aggregate concrete mixtures. Polypropylene fibers, carbon fibers, and steel fibers were employed as fiber additions. The binary mixture had higher density than the remaining mixtures containing one substitute. The behavior of six concrete mixes in addition to the reference mix of ordinary concrete after exposure to temperatures 100, 250, 350 and 450 °C for two hours and then cooled in two ways (water and air) as well as examined directly and the results showed that the concrete mixes containing fiber better behavior compared to other mixtures, especially at high temperature. If left to cool in the air, the lightweight concrete containing Volcanic Pumice can recover its compression strength after being exposed to high temperatures.

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  • 11.
    Abdel, Berivan
    Mälardalen University, School of Business, Society and Engineering.
    Utveckling av en robust strategi för systematiskt brandskydd på sjukhus: En fallstudie om brandskydd på Västerås nya akutsjukhus2024Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Purpose: This essay aims to examine the organizational and technical fire protection for the new emergency hospital in Västerås and analyze what measures are needed to ensure a safe hospital. By involving the staff and ensuring that they have the necessary knowledge and participation, one can ensure a safe care environment for the patients and create the conditions for dealing with potential dangers in an effective manner. Method: To achieve the objectives of the study the method involved carefully selected interviews with various professional roles possessing expertise in fire risks. Through these interviews, the aim was to attain a more comprehensive depiction of the results. In addition to the interviews, a versatile approach was adopted, encompassing surveys, site visits, literature reviews, and meticulous calculations of airlocks. Furthermore, data collection was augmented by utilizing documents from the Västmanland Region. Result: The outcome of the study showed a lack of knowledge, experience and ability to act when it comes to evacuation situations. The building was designed with fire safety in mind. Despite this, the opportunity to implement measures to further improve safety was identified. With regard to the building's fire protection, the possibility of implementing airlocks was identified to supplement and strengthen fire protection in departments where there were fewer fire cells. Conclusion: l the implementation of airlocks is important to improve the evacuation situation and safety. Regular evacuation drills should be prioritized to increase staff preparation and confidence. Measures such as clear fire separations, reliable fire alarm systems, automatic extinguishing systems and well-designed emergency escape routes need to be implemented to increase robustness and improve fire protection. This requires cooperation with fire safety experts. Airlocks can streamline the evacuation process for bedridden patients and staff, which is crucial for quick and safe evacuation in emergency situations. 

  • 12.
    Abdeljaber, Osama
    et al.
    Qatar University, Qatar.
    Hussein, Mohammed
    Qatar University, Qatar.
    Avci, Onur
    Qatar University, Qatar.
    Davis, Brad
    University of Kentucky, USA.
    Reynolds, Paul
    University of Exeter, UK.
    A novel video-vibration monitoring system for walking pattern identification on floors2020In: Advances in Engineering Software, ISSN 0965-9978, E-ISSN 1873-5339, Vol. 139, article id 102710Article in journal (Refereed)
    Abstract [en]

    Walking-induced loads on office floors can generate unwanted vibrations. The current multi-person loading models are limited since they do not take into account nondeterministic factors such as pacing rates, walking paths, obstacles in walking paths, busyness of floors, stride lengths, and interactions among the occupants. This study proposes a novel video-vibration monitoring system to investigate the complex human walking patterns on floors. The system is capable of capturing occupant movements on the floor with cameras, and extracting walking trajectories using image processing techniques. To demonstrate its capabilities, the system was installed on a real office floor and resulting trajectories were statistically analyzed to identify the actual walking patterns, paths, pacing rates, and busyness of the floor with respect to time. The correlation between the vibration levels measured by the wireless sensors and the trajectories extracted from the video recordings were also investigated. The results showed that the proposed video-vibration monitoring system has strong potential to be used in training data-driven crowd models, which can be used in future studies to generate realistic multi-person loading scenarios.

  • 13.
    Abdul Gabar, Allan
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Protic, Dennis
    Halmstad University, School of Business, Engineering and Science.
    Kartläggning av arbetsledarens arbetsfördelning i byggproduktion: En undersökning av möjliga förbättringar inom yrkesrollen2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Every company strives for maximum efficiency. The construction industry, which is complex while margins are small, makes efficiency an important issue. In the construction industry today,the high demand for production is to be delivering high quality projects as well as within certain timeframes. In order for this to be achieved, there is a great demand for work management in production. Therefore, we have chosen to analyze improvement areas within the supervisor’s role.The purpose of this report is to investigate the supervisor’s situation in the construction industry.Furthermore, the purpose is to identify work-related tasks in the professional role that have the potential for efficiency enhancement.A frequency study has been conducted in three different workplaces where we have followed three different supervisors for a total of nine days to get an insight into how the supervisors spend theirtime. Interviews have been conducted with supervisors for an even broader view of the study. Literature search has been made where we have found theories that we also present. During the course of the study we have found that there are a few improvement areas. As an enhancement, we think digitalization should be implemented, and everyone should keep order and clean up afterwards, more feedback to employees, and develop communication.

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  • 14.
    Abdul Hakim, Faisal
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Said, Shazad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    En studie av småhusentreprenader: Varför går det fel?2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to investigate the single-family home construction industry and what problems arise. Furthermore, it was intended that this study would give the public a better idea of why conflicts arise between customers and contractors and how home suppliers work to counteract these problems.

    To achieve the purpose and get answers to the research questions, we used a qualitative research method in the form of semi-structured interviews. The reason why this interview technique was applied was to give respondents the freedom to talk openly about their experiences and views. The respondents interviewed were four representatives of house suppliers, three clients, a building inspector and an inspection manager.

    The results of the interviews showed that there was a common opinion among clients and house suppliers on certain issues, but then there were also opinions that differed. The study showed that customers experience the construction of detached houses as a slow and energy-intensive process. The problems that are common in detached house contracts are that there is a difference in language and knowledge between the involved parties. This results in a lack of communication which in turn can lead to various conflicts.

    Home suppliers are aware of the problems that exist in the industry and work continuously to develop solutions. One such solution is to place great emphasis on documentation and contracts because they are the ones that are legally binding. The conclusion of this study was that good communication results in fewer misunderstandings and conflicts. Conflicts, on the other hand, cannot be completely avoided, but will always arise due to human factors. 

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  • 15.
    Abdul Hamid, Akram
    et al.
    Lund University, Sweden.
    von Platten, Jenny
    RISE Research Institutes of Sweden, Built Environment, System Transition and Service Innovation. Lund University, Sweden.
    Mjörnell, Kristina
    RISE Research Institutes of Sweden. Lund University, Sweden.
    Johansson, Dennis
    Lund University, Sweden.
    Bagge, Hans
    Lund University, Sweden.
    Determining the Impact of High Residential Density on Indoor Environment, Energy Use, and Moisture Loads in Swedish Apartments-and Measures for Mitigation2021In: Sustainability, E-ISSN 2071-1050, Vol. 13, no 10, article id 5446Article in journal (Refereed)
    Abstract [en]

    Recently, there has been an increase in apartments with a large number of inhabitants, i.e., high residential density. This is partly due to a housing shortage in general but also increased migration, particularly in suburbs of major cities. This paper specifies issues that might be caused by high residential density by investigating the technical parameters influenced in Swedish apartments that are likely to have high residential density. Interviews with 11 employees at housing companies were conducted to identify issues that might be caused by high residential density. Furthermore, simulations were conducted based on extreme conditions described in the interviews to determine the impact on the energy use, indoor environmental quality, and moisture loads. In addition, the impact of measures to mitigate the identified issues was determined. Measures such as demand-controlled ventilation, increase of a constant ventilation rate, and moisture buffering are shown to reduce the risk for thermal discomfort, mold growth, and diminished indoor air quality; while still achieving a lower energy use than in a normally occupied apartment. The results of this study can be used by authorities to formulate incentives and/or recommendations for housing owners to implement measures to ensure good indoor environmental quality for all, irrespective of residential density conditions.

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  • 16.
    Abdula, Sham
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Oksman, Dan
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Attefallshus som komplementbostadshus: Drömhus eller mardröm?2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den 2 juli 2014 blev det enligt lag tillåtet för en- och tvåbostadshusägare att uppföra en bygglovsbefriad komplementbyggnad på max 25 kvadratmeter på den egna fastigheten. Rapporten undersöker vilket genomslag lagändringen har haft i Stor-Stockholm, Stor-Göteborg och Stor-Malmö. Undersökningen visar att lagändringen ännu inte har haft något stort genomslag. I rapporten undersöks även en utvald del av marknadsaktörers utbud av attefallshus avsett som komplementbostadshus. 

    Ett attefallshus utformas med miljövänligt hållbara material och inspireras av Vitruvius tre principer för god arkitektur. Huset konstrueras med avsikt att uppfylla kraven som ställs i PBL, PBF, BBR och EKS. Målet med de framtagna bygghandlingarna är att få startbesked från byggnadsnämnden i Växjö. 

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  • 17.
    Abdulhadi, Ahmed
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Brånemo, Oskar
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Jämförelse av betongkonstruktioner som dimensionerats under olika svenska byggnormer2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the construction sector today, there is a lot of discussion about material reuse tominimize the negative environmental impact. By reuse of precast concreteelements, significant amounts of CO2 emissions can be prevented. In order toreuse a concrete element for structural purposes in a building, the element need tobe assessed to ensure it can withstand the required loads.

    This report is based on a comparison of different building codes, it describes andcompares three selected building codes and their associated concrete standardsfrom different eras. The purpose of the report is to compare the results obtainedwhen designing predetermined concrete elements and components. The findingswill indicate whether it is possible to reuse concrete elements that were designedaccording to previous standards. The calculations will demonstrate bothsimilarities and, more importantly, differences in the design approaches of thebuilding codes and how they have evolved.

    An investigation concludes that by employing a chain of checks, it is possible todetermine if an existing component is reusable considering its load capacity.

    The differences in reinforcement content vary within approximately 0-25% infavor of the previous code, i.e. the older code requires more reinforcement.

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  • 18.
    Abdulhalim, Mohammed
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Angmyr, Sebastian
    Tillämpning av Partnering vid ombyggnad av bostäder: Vad krävs för ett framgångsrikt partnering projekt?2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
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  • 19.
    Abdulkader, Ammar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Förseningar i byggprojektering och hur de kan förebyggas2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Idag är förseningar inom byggbranschen vanliga och orsakar problem och konsekvenser i byggprojekt. När ett projekt blir försenat uppstår extra kostnader för projektägaren, entreprenören eller båda parter. Med andra ord innebär förseningar ekonomiska förluster och skapar en stressig arbetsmiljö för alla inblandade aktörer och projektmedlemmar. I detta examensarbete identifieras betydande risker som kan orsaka förseningar i projekteringsfasen av byggprocessen, samt presenteras lösningar för att förebygga dem.

    Byggprocessen består av fyra faser: förstudie, projektering, produktion och överlämning. Projekteringsfasen är ett av de viktigaste stegen i byggprocessen och har stor betydelse för att förebygga förseningar. I denna fas utformas och ritas byggnader, och bygghandlingar tas fram med konstruktionsritningar, tekniska lösningar och beskrivningar upprättas för att styra hela byggprocessen.

    Detta arbete fokuserar på förseningar i själva projekteringsfasen och dess påverkan på hela projektet, samt hur de kan förebyggas. Arbetet består av en teoretisk och en praktisk del. Syftet med arbetet är att undersöka orsakerna till förseningar inom projekteringsfasen och att hantera dem på bästa sätt genom att utveckla riskhanteringen. Orsakerna kan vara ofullständig information, förändringar i projektspecifikationer och tekniska problem. Teorin bygger på litteratur om projektering i byggprocessen för att ge en bred kunskapsbas om projektering innan den praktiska delen genomförs. Den praktiska delen baseras på intervjuer med erfarna projektledare inom projektering som har varit involverade i olika försenade projekteringsprocesser. Resultatet presenterar projektledarens svar angående orsakerna till förseningarna i de två projekten. I diskussionen jämförs och analyseras resultaten med teorin, vilket visar att sjukdomar och bristande kommunikation, tillsammans med andra risker, kan vara orsaker till förseningar i projekteringsfasen. Förbättringsförslag inkluderar att skapa en trygg och hälsosam arbetsmiljö som en viktig faktor för projektets framgång, genom att anlita ytterligare konsulter från andra företag vid arbetsbelastning och erbjuda avkopplande aktiviteter som exempelvis spa-besök när det behövs. Andra förslag innefattar att lägga extra tid på riskanalys för att identifiera potentiella problem samt att etablera en kommunikationsmetod för grupper, såsom en grupp på Messenger eller en annan applikation, där all information om projektet regelbundet delas.

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  • 20.
    Abed, Ahmed Ghafel
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energieffektivisering vid renovering av Lamellhus på Mariehemsvägen2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In Sweden more houses than ever before are being built, and the house production is moving forward. At the same time, awareness of the energy use of buildings and its accompanying impacts on climate and sustainability are increasing. Therefore, Boverket constantly raises the demands for the energy performance of newly built and refurbished buildings.

    According to current requirements from Boverket (BBR, 2017), the primary energy value for apartment buildings may not be more than 85 kWh per square meter of tempered floor space and year. This also applies according to future requirements in 2021, but with the difference that the average U-value will decrease from 0.4 to 0.35 W/m2 K which means that apartment buildings must be built in an efficient way to reduce energy use. A large part of new construction and newly refurbished apartment buildings must then implement energy efficiency measures on their buildings to meet future requirements.

    This degree project has been carried out in collaboration with Rikshem AB who wants to investigate the impact of various energy efficiency measures on their apartment building ”Lamellhus”. The aim is to theoretically reduce apartment buildings ”Lamellhusets” specific energy use from 187,4 to 70 kWh/m2 Atemp, year and thus reduce the primary energy enough to meet future requirements according to BBR near-zero energy building.

    To theoretically reduce specific energy use and thus primary energy value, the project through manual calculations and with the help of computer tools examined various energy efficiency measures on the building's construction and installation system.

    The results show that the measures on the property climate shell are sufficient to meet the requirements. If all the measures according to package 1 or 2 on the design are combined, specific energy use according to BBR 16 (2010) will be at 83-94 kWh/m2 Atemp, year and the primary energy value according to BBR 25 (2017) will be at 68-77 kWh/m2 Atemp, year.

    The results also show how much of a building's energy use is ventilated. Replacing the ventilation system from F-systems to FTX-systems on the reference house in the base case, is the measure that gives one of the greatest impacts with a heat saving of (25.5-26.7%). In combination FTX-system with district heating, specific energy consumption can be reduced as low as possible. If the operation with the FTX-system is applied together with the existing district heating and all measures on the construction according to package 1 or 2, this gives a reduction of approximately (70-75 %) compared to the base case corresponding to 42-51 kWh/m2 Atemp, year according to BBR 16 and according to BBR 25, the figures are even lower. If the calculation considers thermal bridges and air leakage in the house, the result will increase.

    The results also show that the investment repays itself after 15-16 years with a simplified payback. With a calculation rate of 5 %, it is profitable over 30-31 years or more, but with a calculation rate of 8 % it is not profitable.

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    Energieffektivisering vid renovering av Lamellhus på Mariehemsvägen
  • 21.
    Abrahamsen, Rune
    et al.
    Moelven Limtre, Norway.
    Bjertnaes, Magne A.
    Sweco, Norway.
    Bouillot, Jacques
    Eiffage, France.
    Brank, Bostjan
    University of Ljubljana, Slovenia.
    Cabaton, Lionel
    Arbonis, France.
    Crocetti, Roberto
    Moelven, Sweden.
    Flamand, Olivier
    CSTB, France.
    Garains, Fabien
    Eiffage, France.
    Gavric, Igor
    InnoRenew, Slovenia.
    Germain, Olivier
    Galeo, France.
    Hahusseau, Ludwig
    Eiffage, France.
    Hameury, Stephane
    CSTB, France.
    Johansson, Marie
    RISE, Sweden.
    Johansson, Thomas
    Moelven, Sweden.
    Ao, Wai Kei
    University of Exeter, UK.
    Kurent, Blaz
    University of Ljubljana, Slovenia.
    Landel, Pierre
    RISE, Sweden.
    Linderholt, Andreas
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Malo, Kjell
    NTNU Norwegian University of Science and Technology, Norway.
    Manthey, Manuel
    CSTB, France.
    Nåvik, Petter
    Sweco, Norway.
    Pavic, Alex
    University of Exeter, UK.
    Perez, Fernando
    Smith and Wallwork, UK.
    Rönnquist, Anders
    NTNU Norwegian University of Science and Technology, Norway.
    Stamatopoulos, Haris
    NTNU Norwegian University of Science and Technology, Norway.
    Sustersic, Iztok
    InnoRenew, Slovenia.
    Tulebekova, Salue
    NTNU Norwegian University of Science and Technology, Norway.
    Dynamic Response of Tall Timber Buildings Under Service Load: The DynaTTB Research Program2020In: EURODYN 2020, XI international conferece on structural dynamics: Proceedings, Volym II / [ed] M. Papadrakakis, M. Fragiadakis, C. Papadimitriou, National Technical University of Athens , 2020, p. 4900-4910Conference paper (Refereed)
    Abstract [en]

    Wind-induced dynamic excitation is becoming a governing design action determin-ing size and shape of modern Tall Timber Buildings (TTBs). The wind actions generate dynamic loading, causing discomfort or annoyance for occupants due to the perceived horizontal sway – i.e. vibration serviceability failure. Although some TTBs have been instrumented and meas-ured to estimate their key dynamic properties (natural frequencies and damping), no systematic evaluation of dynamic performance pertinent to wind loading has been performed for the new and evolving construction technology used in TTBs. The DynaTTB project, funded by the Forest Value research program, mixes on site measurements on existing buildings excited by heavy shakers, for identification of the structural system, with laboratory identification of building elements mechanical features coupled with numerical modelling of timber structures. The goal is to identify and quantify the causes of vibration energy dissipation in modern TTBs and pro-vide key elements to FE modelers.

    The first building, from a list of 8, was modelled and tested at full scale in December 2019. Some results are presented in this paper. Four other buildings will be modelled and tested in spring 2020.

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  • 22.
    Abrahamsen, Rune
    et al.
    Moelven Limtre, Norway.
    Bjertnæs, Magne A.
    Sweco, Norway.
    Bouillot, Jacques
    Eiffage, France.
    Brank, Boštjan
    University of Ljubljana, Slovenia.
    Crocetti, Roberto
    Moelven SE, Sweden.
    Flamand, Olivier
    CSTB, France.
    Garains, Fabien
    Arbonis, France.
    Gavrić, Igor
    InnoRenew, Slovenia.
    Hahusseau, Ludwig
    Eiffage, France.
    Jalil, Alan
    CSTB, France.
    Johansson, Marie
    RISE, Sweden.
    Johansson, Thomas
    Moelven, Sweden.
    Ao, Wai Kei
    Uni Exeter, UK.
    Kurent, Blaž
    University of Ljubljana, Slovenia.
    Landel, Pierre
    Linnaeus University, Faculty of Technology, Department of Building Technology. Rise, Sweden.
    Linderholt, Andreas
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Malo, Kjell
    NTNU, Norway.
    Manthey, Manuel
    CSTB, France.
    Nåvik, Petter
    Sweco, Norway.
    Pavic, Alex
    Uni Exeter, UK.
    Perez, Fernando
    Smith&Wallwork, Switzerland.
    Rönnquist, Anders
    NTNU, Norway.
    Šušteršič, Iztok
    InnoRenew, Slovenia.
    Tulebekova, Saule
    NTNU, Norway.
    Dynamic response of tall timber buildings under service load: results from the dynattb research program2023In: World Conference on Timber Engineering 2023 (WCTE 2023): Timber for a Livable Future, 19-22 june, 2023,Oslo, Norway / [ed] Nyrud, A. Q. and Malo, K. A. et al., Curran Associates, Inc., 2023, p. 2907-2914Conference paper (Refereed)
    Abstract [en]

    Wind-induced dynamic excitation is a governing design action determining size and shape of modern Tall Timber Buildings (TTBs). The wind actions generate dynamic loading, causing discomfort or annoyance for occupants due to the perceived horizontal sway, i.e. vibration serviceability problem. Although some TTBs have been instrumented and measured to estimate their key dynamic properties (eigenfrequencies, mode shapes and damping), no systematic evaluation of dynamic performance pertinent to wind loading had been performed for the new and evolving construction technologies used in TTBs. The DynaTTB project, funded by the ForestValue research program, mixed on site measurements on existing buildings excited by mass inertia shakers (forced vibration) and/or the wind loads (ambient vibration), for identification of the structural system, with laboratory identification of building elements mechanical features, coupled with numerical modelling of timber structures. The goal is to identify and quantify the causes of vibration energy dissipation in modern TTBs and provide key elements to finite element models. This paper presents an overview of the results of the project and the proposed Guidelines for design of TTBs in relation to their dynamic properties.

  • 23.
    Abrahamsen, Rune
    et al.
    Moelven Limtre, Norway.
    Johansson, Marie
    RISE Research Institutes of Sweden, Built Environment, Building and Real Estate.
    Tulebekova, Saule
    NTNU, Norway.
    DYNAMIC RESPONSE OF TALL TIMBER BUILDINGS UNDER SERVICE LOAD – RESULTS FROM THE DYNATTB RESEARCH PROGRAM2023Conference paper (Refereed)
    Abstract [en]

    Wind-induced dynamic excitation is a governing design action determining size and shape of modern Tall Timber Buildings (TTBs). The wind actions generate dynamic loading, causing discomfort or annoyance for occupants due to the perceived horizontal sway, i.e. vibration serviceability problem. Although some TTBs have been instrumented and measured to estimate their key dynamic properties (eigenfrequencies, mode shapes and damping), no systematic evaluation of dynamic performance pertinent to wind loading had been performed for the new and evolving construction technologies used in TTBs. The DynaTTB project, funded by the ForestValue research program, mixed on site measurements on existing buildings excited by mass inertia shakers (forced vibration) and/or the wind loads (ambient vibration), for identification of the structural system, with laboratory identification of building elements mechanical features, coupled with numerical modelling of timber structures. The goal is to identify and quantify the causes of vibration energy dissipation in modern TTBs and provide key elements to finite element models. This paper presents an overview of the results of the project and the proposed Guidelines for design of TTBs in relation to their dynamic properties.

  • 24.
    Abrahamsson, Alexandra
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Arbetsmiljöarbetet på SverigesBostadsrättsCentrum: Vad ändringarna i arbetsmiljölagen innebär2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This diploma work was performed because the company Sveriges BostadsrättsCentrum, with the abbreviation SBC, had a need to gain insight into how changes in the Work Environment Act and related regulations which took effect January 1, 2009 affecting their work with the work environment. The changes mean that the client may hand over his work environment responsibilities to a contractor and that he has to select so-called building work environment co-ordinators. At SBC they are working as representatives for tenant-owner's association when a construction is about to be carried out. The purpose was to ascertain how changes may affect the work at SBC. The diploma work intends to educate the staff at SBC how work with the work environment would look like if they met the regulatory requirements. The main issue that the diploma work deals with is whether SBC has the responsibility to select a building work environment co-ordinator for the planning and projecting before the contractor takes over responsibility for the work environment. Questions were answered by information from the Work Environment Act, AFS 1999:3 and other material from the Work Environment Authority. Two interviews with staff at the Work Environment Authority were also held. One of the conclusions drawn from the diploma work is that it’s the client who will select a building work environment co-ordinator for the planning and projecting. That should be done as soon as the planning and projecting has begun. The planning and projecting usually begins before the main contractor takes over responsibility for the work environment as the employee. It is not clear that SBC will take on the client’s responsibility to select a building work environment co-ordinator for the planning and projecting in the early planning, before the contractor takes on responsibility and there are several ways to do this.

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  • 25.
    Abrahamsson, Caroline
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Waltersson, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    FLEXIBLA BYGGNADER: Utformning av en förskola med en möjlig verksamhetsändring för framtida behov2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Society today has an increasing demand for environmentally and economically sustainable developments in order to create a sustainable society. Society’s growth in new construction is a big part of this, and by planning and building more sustainable buildings these requirements can be fulfilled. The development of flexible buildings, which can adapt to future needs of society, lead to a more efficient utilization and longevity of premises and generate more sustainable buildings.In Sweden, the municipalities are the country’s largest property developers and therefore have a significant responsibility to provide society with real estate and public buildings. In recent time we have seen a shift towards flexible public buildings and in particular preschools. With the current socio-economic climate and ageing population buildings like preschools need to be flexible to ensure they can cater for future demands of society.

    This degree project, within the Bachelor programme in Construction Engineering, has been carried out during 10 weeks on Tengbom Architects in Uppsala. The thesis deals with the subject of flexibility in buildings and includes a proposal for the design of a flexible building as a pre-school that in the future can be converted into a retirement home.

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  • 26.
    Abrahamsson, Jenny
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    la Fleur, Filip
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    The impact of connection stiffness on the global structural behavior in a CLT building: A combined experimental-numerical study2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Cross Laminated Timber (CLT) has in recent years become a more important building material. This means that the demand for accurate calculation methods in building standards such as Eurocode 5 has increased. There is limited knowledge about the connections in CLT buildings which is an important part of a CLT structure. This thesis was therefore focused on investigating a wall-floor-wall type connection commonly found in platform type buildings. 

    An experimental and numerical study on typical wall-floor-wall connections was carried out in this thesis. In the experimental part 60 tests with 8 different configurations were conducted to investigate the influence of different parameters on the connection, moment capacity and rotational stiffness. During the tests the deformation of the specimens under four load levels were investigated. Compression tests were also performed on the specimens to determine the compressive strength and stiffness of the elements. In the numerical part two different models for the connection were created. One simplified model with rotational springs and one more complex model with compression springs. With these models the influence from the number of stories, span and thickness of the wall on the global behavior of a structure was investigated. 

    The result from this thesis shows that there is both moment capacity and rotational stiffness in the wall-floor-wall type connection that can be utilized in the design phase of a structure. This was proven by both the experimental and the numerical study. The parameters that influence the behavior of the connection most were the load level applied on the wall and the wall thickness. The model created in the numerical study showed great potential regarding the replication of the connection behavior observed in the experimental study.  

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  • 27.
    Abrahamsson, Mickael
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Berg, Simon
    Halmstad University, School of Business, Engineering and Science.
    Tillfälliga modulhus - en ekonomisk och kvalitetsmässig analys2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The populations of Sweden are right now facing an acute housing shortage. One of the reasons of this is the huge amount of immigrants that have been taken in over recent years. The construction industry hasn’t been able to keep up with the rising demand and is right now looking for a solution. Modular housing is one solution that has been proposed by Boverket, the national board of housing, building and planning as it reduces construction times. The purpose of this paper is to analyze this method and the potential consequences/gains it has. In this paper we have used three different case studies were we have done 3 interviews in each.   This research concludes that the problem doesn’t lie within the quality or the costs associated with modular housing. It lies within the temporary building permits that are often used when time is of the essence. 

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  • 28.
    Abrahamsson, Nora
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Söderström, Fanny
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Påbyggnad av bostäder på tak i Stockholm City: En möjlighet för att göra Stockholm City till en funktionsblandad och mer levande stadsdel2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Stockholm City is currently well composed in the aspect of commercial and public service. A consequence to this is a desolated City during the late night. A requirement to accomplish a more living inner city is a satisfying combination of functions whereas people are in motion between the home, work and other social activities. The main function missing today in City is habitats. A problem with supplying more accommodations in City is however the limited asset of ground area due to exploitation.

    In this thesis research is made whether it is possible to transform City into a mixed-function and thereby urban living area. With reference to the limited asset of ground area aswell as the opportunity to preserve the existing qualities that occupy these areas, a research is conducted for the purpose of more residential buildings with the method of expansion of existing buildings.

    The result of this thesis is a proposition for residential buildings on roof tops in City and the requirements for such project are being analyzed. The additional building is added to a specific building and by its shaping reflects a good residential environment and a design appropriate to the surrounding built-up area. The proposal consists of a rooftop landscape with eight pairs of houses. To insert accommodations throughout expansion of existing buildings generally is applicable in City and therefore an adequate solution to the problem considering the problems in the area.

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  • 29. Abrahamsson, Sam
    et al.
    Rosén, Eric
    Entreprenörer och konsulters hantering av byggmaterialens prisökning och tillgängligheten på byggmaterial i Sverige under Covid-19.2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 30.
    Abu Sulaiman, Iyad
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Ibrahim, Miran
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Framställning av dränerande bärlager från bergtäkt2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Bearing layers are used in road and building constructions as underlying soil layers to provide stability and support to the top layer that takes up the load. A normal bearing layer contains different amounts of materials such as stone, gravel, and filler. That mixture of materials contains a large amount of filler to give the product tightness and stability. Draining bearing layers usually contain less filler than ordinary bearing layers, because their purpose is to improve the drainage properties and reduce the risk of damage due to water collection.This thesis work took place at NCC's quarries in Sälgsjö and Hammarby. At NCC's rock quarry, there already is a standard bearing layer with a grain size of 0/32 and a filler content of approximately 4–5%. In this degree project, a production process has been created to obtain a drain bearing layer where the filler content is reduced to approximately 2–3%. The requirement for a draining carrier layer is 2–3% filler content and this requirement has been followed in this production process. The draining bearing layer has been produced based on a standard product with the same grain size.There are practical limitations in how the operations work and what capabilities are required. Moisture in the material has also been a limitation. In this project, work is done with freshly crushed material, which has a relatively low moisture content (1–2%). A vibration-free screen like the function of the harp has been designed and built. Then the standard product was run through the harp at different gradients and the new product was analyzed in the lab to see what filler content was achieved. A simulation test was performed using a FEM design program called Digiroad at Chalmers University of Technology in Gothenburg.The results demonstrate that the utilization of the developed models of harp screens reduces the proportion of filler in the material. Additionally, the conducted harp screen analyses confirm that the designed harp screens are effective in transforming a standard bearing layer into a draining bearing layer, which helps to prevent water accumulation under roads or buildings and thus reduces the risk of damage and problems. The efficient production process for producing draining bearing layers can be of great importance to ensure a sustainable and safe infrastructure.

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  • 31.
    Abushaqfa, Omar
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Bakero, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Materials brandförmåga för mellanväggar2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nowadays, architects, designers and engineers pay a lot of attention to fire safety in buildings.Due to the high number of accidents, fire safety in construction is becoming increasinglyimportant.In order to use more fire-resistant material in the structure, attention was paid to the propertiesof the materials used. The material has begun to be evaluated for standard resistance and somestandard tests have been developed. Based on how long the material did not show anysignificant damage, these materials were evaluated and graded. This classification can beaccessed from Eurocodes (Svensk trä,2022).Timber was used in construction even before history was written. Since the ancient civilization,wood has been an important building material.Wood exhibits great resistance to fire due to its self-insulating property.When wood burns, it first chars to a certain depth. Then the outer charred layer acts as a barrierand suppresses the fire. This fire-extinguishing property in itself is the wood's self-insulatingproperty. (Swedish wood, 2021).Fire exposure usually occurs according to the standard fire curve that describes a fullydeveloped fire as defined in EN 1363-1. Building parts must withstand fire for a certain time,for example 60 minutes. With wooden constructions, it is possible to achieve high fire resistancewith the help of insulating material (EI). (Swedish wood, 2021).In the first part of the thesis, the properties of wood as a building material are discussed. INthe next part discusses the fire classes Br0, Br1, Br2 and Br3 for buildings. After that, the readercan learn about how a building can be divided into sections depending on its fire rating. Amaterial investigation will be done to be able to see the fire properties of certain materials thatwe will add to or remove from the wall such as extra plasterboard or insulation material withoutchanging the thickness of the wall to make them more fireproof and to be able to last longerwithout the fire spreads to the other spaces with the help of better material ability. (Swedishwood, 2021).This work also presents the theory behind wall fire sectioning in terms of materials and thevarious fire engineering solutions with some examples of calculations relating to the fireresistance of the materials, with references to the instructions in SS-EN 1995-1-2:2004/AC:2010. Finally, the results are analyzed and compared with different materials. Usingthe results of reactions of different types of materials and insulation, the fire resistance ofwooden walls can be discussed in more detail.Results show that gypsum boards combined with stone wool is the best choice of material forcreating fireproof partition walls. The results of our calculations show that double gypsumboards on each side with a thickness of 15 mm combined with stone wool with a thickness of95 mm provides fire resistance up to 109 minutes. Compared to a partition wall with a gypsumboard on each side without insulation, fire resistance is up to 48 minutes. This has beenemphasized with a study where the fire resistance has been investigated for walls, they havefound that double gypsum board combined with stone wool with the right conditions providesfire resistance up to 142 minutes. However, it is crucial for fire resistance to work that theinstallation is carried out correctly. All resulting screws must be placed correctly, there must beno holes on the gypsum boards and the number of gypsum boards and insulation thicknesstogether with the correct assembly provides better fire protection. This is based on the resultsthat have been obtained from articles, calculation during this work and from interviews withthe companies that work with requirements, manufacture and installation of fireproof partitionwalls. 

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  • 32.
    Adevik Hammensten,, Sebastian
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Axelsson, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Solsidan – Utnyttjande av solenergi i småhus2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 33.
    Adhi, Boma
    et al.
    RIKEN, Ctr Computat Sci R CCS, Wako, Saitama, Japan..
    Cortes, Carlos
    RIKEN, Ctr Computat Sci R CCS, Wako, Saitama, Japan..
    Tan, Yiyu
    RIKEN, Ctr Computat Sci R CCS, Wako, Saitama, Japan..
    Kojima, Takuya
    RIKEN, Ctr Computat Sci R CCS, Wako, Saitama, Japan.;Univ Tokyo, Grad Sch Informat Sci & Technol, Tokyo, Japan..
    Podobas, Artur
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Computational Science and Technology (CST).
    Sano, Kentaro
    RIKEN, Ctr Computat Sci R CCS, Wako, Saitama, Japan..
    Exploration Framework for Synthesizable CGRAs Targeting HPC: Initial Design and Evaluation2022In: 2022 IEEE 36Th International Parallel And Distributed Processing Symposium Workshops (IPDPSW 2022), Institute of Electrical and Electronics Engineers (IEEE) , 2022, p. 639-646Conference paper (Refereed)
    Abstract [en]

    Among the more salient accelerator technologies to continue performance scaling in High-Performance Computing (HPC) are Coarse-Grained Reconfigurable Arrays (CGRAs). However, what benefits CGRAs will bring to HPC workloads and how those benefits will be reaped is an open research question today. In this work, we propose a framework to explore the design space of CGRAs for HPC workloads, which includes a tool flow of compilation and simulation, a CGRA HDL library written in SystemVerilog, and a synthesizable CGRA design as a baseline. Using RTL simulation, we evaluate two well-known computation kernels with the baseline CGRA for multiple different architectural parameters. The simulation results demonstrate both correctness and usefulness of our exploration framework.

  • 34.
    Adiego Abad, Sonia
    Halmstad University, School of Business and Engineering (SET).
    Degree project:HOSTEL2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A construction project including planning, cost estimation and design of a Hostel on a property in the city of Halmstad.

  • 35.
    Adolfsson, Rasmus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Utformning av en infästningsstandard: En utveckling av kvalitetsarbetet hos Nordmarkens Fasader AB2015Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    As the construction industry today is increasing the demands on its actors and procedures to ensurethe quality of the final product, the work on quality assurance has increased in a greater degree.Quality assurance involves a systematic approach that often follow a specific quality system orquality mark. That this is conducted is often demonstrated by a certain certification.Nordmarkens Fasader in Töcksfors is a manufacturer and installator of windows, doors, walls androofs in aluminum and glass. To ensure the quality of their products, they work for the P-markingsystem that later allows them to P-label their products. The P-mark is the Science Partners ownquality mark and proves, among other things, that the product complies with statutory or regulatoryrequirements but also in most cases higher standards demanded by the market.In their work, Nordmarkens Fasader follows a quality manual, which in its turn is modeled after therules for P-marking. This is the official summarized description of the P-marking and contains orrefers to all the documents and document types included in the quality system of NordmarkensFasader.For the products of Nordmarkens Fasader to be developed a further step in working towards a goodquality and function, they want to establish drawings that deal with attaching elements in the wall, inthe quality manual. All this to get better track of what happens to the product after manufacture.Something that makes this even more important is that they do not always handle assembly of theirproducts. A standard of attachments in this case would result in that they can influence whathappens after manufacture. To achieve this it was necessary for a standard of attachments ofelements to be designed and then also integrated in the quality manual.Because there are many wall types to choose from, the most common and most abundant of thesewas elected. It all resulted in a number of standard drawings showing where some of the products ofNordmarkens Fasader should be attached in the selected wall. For this to be put into use in everydaylife it also had to be integrated into the quality manual. In addition to these standard drawings, themanual were changed while new documents also were created in this. All to achieve the best resultswith the quality work at Nordmarkens Fasader.This work will serve as a basis for future work on attachment drawings, in the quality manual, asthere is interest in bringing in multi-wall types in this.

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  • 36.
    Adolfsson, Robin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Jönsson, Caroline
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Är SundaHus materialklassning kompatibel med Miljöbyggnads, BREEAMs och LEEDs materialkrav?: En studie om SundaHus miljöklassningar.2015Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    We live in a society where there is a shortage of housing and the demand for new and sustainable buildings is growing. The houses that are being built today are focused on being energy efficient to save resources. Something that is forgotten is the choice of materials to house constructions. Materials can affect nature and people from the cradle to the grave by for example material hazardous components. The certification systems Miljöbyggnad, BREEAM and LEED have been checked and their material criteria have been defined. Through a selection of construction materials taken from SundaHus a review has been made of these materials towards the certification systems´ criteria on materials to see if they are compatible. The minority of the criteria were reviewed to separate materials and could be verified in SundaHus. Almost all materials passed the criteria that could be used of Miljöbyggnad and BREEAM regardless of classification in SundaHus. None of the LEED criteria were compatible with SundaHus for separate materials. The fact that the worse classifications in SundaHus could pass the criteria that were reviewed indicates that the requirements in environmental certification systems are too low. Higher and more demands should be made on individual materials and the hazardous substances in them.

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  • 37.
    af Klintberg, Tord
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Heated air gaps: a possibility to dry out dampness from building constructions2008Licentiate thesis, comprehensive summary (Other scientific)
    Abstract [en]

    The air gap method is a modification of the common way of building indoor walls and floors. The aim of the method is to make a construction, less fragile to water damage, with air gaps where moisture can be removed with a thermally driven air flow, caused by a heating cable. The thesis includes a number of experimental studies of this method.

    Temperature and convective air flow in a vertical air gap was studied and it was noted how air flow increased with raised power of the heating cable. The air flow for one meter of wall varied between 50 m3/day (13 air changes per hour) and 140 m3/day (36 air changes per hour). The lower value was caused by a temperature difference in the range 0.2-0.3 oC. Without heating no air flow was found.

    In studies of moisture and RH in wet “slab on ground” constructions, it was noted how the slab in the room with the air gap method dried to a much higher extent than the slab in the room built in an ordinary way. It was also noted that moisture was transported from the air gap in the floor and up through the air gap in the wall. In the room with the air gap construction, the RH values beneath the floor was at a lower level (and below 75 % RH) than the RH values beneath the floor of conventional construction. Mould does not grow below 75 % RH.

    In the study of a flooded intermediate floor it was noted how the thermally driven convective air flow evidently speeded up drying of the construction. Mould growth was only noted in the case where the heating cables were turned off.

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  • 38.
    af Klintberg, Tord
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Björk, Folke
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Air gap method: measurements of airflow inside air gaps of walls2008In: Structural Survey, ISSN 0263-080X, E-ISSN 1758-6844, Vol. 26, no 4, p. 343-363Article in journal (Refereed)
    Abstract [en]

    Purpose - Water damage is a severe problem in modern construction, causing economic loss and health implications. By using the patented Air Gap Method inside building constructions, harmful water in the construction can be dried out. The method drains and ventilates air gaps inside walls and floors with an airflow driven by thermal buoyancy caused by a heating cable in vertical air gaps. This paper aims to investigate this method and measurements of airflow inside air gaps of walls. Design/methodology/approach - This study investigates the measured correlation between the power of the heating cable, the difference of temperature inside and outside the air gap, and the airflow. Data are collected by experimentation with a full-scale constructed wall. Findings - The study finds that airflow increases with raised temperature difference between the air gap and room and with raised power of the heating cable. The measured airflow reaches values up to 140 m3/metre wall and day for one cable. A small increase in temperature, between 0.2 and 0.3 oC inside the vertical air gap results in an air flow of approximately 60 m3/metre wall and day. The air change rate per hour for the air inside the wall construction varies between 15 times for a 6 W/m cable and 37 times for a 16 W/m cable. Practical implications - The method provides the means to build houses in a more robust way, minimising the negative effects of water damage. This investigation provides an understanding of how temperature and ventilation are related in this method of construction. Originality/value - The issue of ventilated construction is rarely investigated in scientific research.

  • 39.
    af Klintberg, Tord
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Högberg, Lovisa
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Björk, Folke
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Stegvis renovering2020Report (Other academic)
    Abstract [sv]

    Den tekniska utvecklingen medför att det finns ett ökande utbud av metoder för att göra renovering stegvis. Det finns också en utveckling mot att renoveringsåtgärder kan göras kortvarigt, så att de boende inte behöver störas så svårt.

     

    Det går att genomföra en stegvis renovering på ett flertal teknikområden, exempelvis av rör, badrum, fönsterbyten. Utvecklingen av relining i olika typer av rör och kanaler har inneburit en stor förändring i och med att åtgärder för renovering kan göras i stort sett utan att riva i stommar och schakt, även i fall då rör och kanaler är ingjutna. Både resultat av experiment i detta projekt och insamlade erfarenheter visar att relining är ett koncept som nu är i stark utveckling och som kommit för att stanna. Användning av relining är även gynnsamt ur ett LCA-perspektiv.

     

    Stegvis renovering ger ofta ett mer ekonomiskt och ett mindre komplext renoveringsförfarande. Bland annat gäller:

    • När systemen renoveras i taget, så optimeras livslängden för dem, vilket är kostnadseffektivt.
    • Det är mer hanterbart att bara renovera ett system i taget och arbetet blir mer effektivt.
    • Stegvis renovering minimerar antalet inblandade yrkesgrupper och minimerar då även missförstånd mellan dessa yrkesgrupper och missförstånd med beställare och boende.
    • Omvärldsfaktorer kan bättre kontrolleras vid stegvis renovering och arbetet blir då mer industriellt och därmed och effektivare.
    • Om byggnadens system renoveras ett i taget som kortvariga kampanjer, så ökar möjligheten för boende att bo kvar under processen, vilket sparar pengar för fastighetsbolaget.
    • Stegvis renovering gör det lättare för byggherren att behålla kontrollen över projektet, bland annat förenklas upphandlingsprocessen.

     

    Nuvarande lagstiftning hindrar en värd att ta betalt för underhåll. Detta är ett arv från den bostadssociala utredningen, som tillsattes 1932. Då var byggnads- och boendesituationen helt annorlunda än nu, exempelvis avseende inomhusmiljö och hygien. Det fanns då många bostäder med usel uppvärmningssituation utan varmvatten och många bostäder med torrdass på gården. Det fanns inte heller någon allmännytta som kunde hålla hyror på en rimlig nivå för ett flertal, istället fanns det somliga hyresvärdar som utnyttjade en bostadsbrist med ohemula hyror. Det var då fullt rimligt att den bostadssociala utredningen kom fram till att en hyresvärd endast skulle kunna höja hyran om det gjordes standardhöjningar. Om bostadssituationen då hade liknat dagens ur ett inomhusmiljö- och hygienperspektiv kan man undra ifall utredningen kommit till samma resultat.

     

    Fortfarande är det så att en hyresvärd bara kan göra hyreshöjningar för underhållsåtgärder om alla hyresgäster går med på det. Om en boende tar frågan till hyresnämnden så kommer värden att fällas och hyreshöjningen accepteras inte. Fastighetsägaren är alltså tvungen att tillgripa standardhöjande åtgärder och dessa kan vara väl så dyra om inte dyrare för de boende än de nödvändiga underhållsåtgärderna. Det finns då en risk att en oseriös fastighetsägare genomför standardhöjande åtgärder och höjer hyran utan att vidta nödvändigt underhåll. En fastighet med höga hyror kan sedan säljas. Till slut blir hyresgästerna drabbade, både av höga hyror och av ett hyreshus, utan fungerande system. Lagen bör ändras, så att om en majoritet av de boende accepterar att betala för underhållsåtgärder så bör detta gälla. Dessutom bör en majoritet av de boende acceptera standardhöjande åtgärder för att dessa ska bli av.

     

    Stegvis renovering har tillämpats fullt ut vid Knivstabostäders renovering, som resulterade i hyreshöjning på 13 %. En förutsättning för detta var dels att fastighetsbolaget var helt transparenta med ekonomin, undvek fördyrande standardhöjande åtgärder och fick ta betalt för sina underhållskostnader.

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  • 40.
    af Klintberg, Tord
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Sustainable Buildings.
    Högberg, Lovisa
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Building and Real Estate Economics.
    Brick, Karolina
    Riksbyggen.
    Björk, Folke
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Kristoffersson, Jan
    Sustainable innovation.
    Riksbyggens renoveringsverkstad 2: Energieffektivisering i samband med renovering hos bostadsrättsföreningar2012Report (Other academic)
    Abstract [en]

    The results of this project show that the main barrier is financial. It is difficult to justify measures such as additional insulation of facades or heat recovery from ventilation air, If you do not count with any real rising in energy prices. The individual cases can of course differ and it is important to examine the profitability of investments in connection with the planning of major maintenance and refurbishment. Ongoing technology development may also contribute to make this kind of measures more interesting in the future. The result from the previous project that optimizing measures (eg adjustment of the heating system) often are very profitable is also confirmed in this project. The economy would naturally be affected by introduction of policy instruments and incentives. However, it is quite doubtful to prioritize instruments for reducing heat used in apartment buildings, since this to a large extent is produced from renewable energy sources (compared to eg traffic).

    The project has also studied how the banking and insurance sectors could contribute to more energy efficiency in housing cooperatives. The conclusion is that these industries have a rather marginal ability to influence. However, there may be a possible "trigger effect” if there are special offers on the market for associations, actively working with their energy efficiency. The work continues to explore different possibilities in that area.

    The project has studied Riksbyggen’s current range of energy related services and has several suggestions for additional services and processes. This applies both to the long-term financial planning, which is an important factor for the cooperatives to be properly prepared for larger investments, and the more short-term / operational planning when the cooperatives are approaching decisions on major maintenance measures. Related to this, various forms of training, especially for the boards of the cooperatives, is of great importance. The project proposes a broad educational effort, based on role-playing. Riksbyggen may also develop the role as a competent discussions partner to the cooperatives and also encourage networking among housing cooperatives for facilitating dissemination of information and perhaps even coordination of efforts.

     

    This project is a direct continuation of the Riksbyggen’s renovation workshop. That project has analysed barriers to more extensive energy saving processes and how these can be bridged, based on housing cooperatives and the environment they are a part of. The project Riksbyggen’s renovation workshop was conducted as a joint project of Riksbyggen, KTH and Sustainable Innovation in 2010-2012 with the aim to highlight good examples of renovation efforts of housing cooperatives ,that can help reduce energy consumption. The project showed that there are good economic potential for energy savings, mainly through operational optimization and other less extensive measures.

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  • 41.
    af Klintberg, Tord
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Jóhannesson, Gudni
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Björk, Folke
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Air gaps in building construction avoiding dampness and mould2008In: Structural Survey, ISSN 0263-080X, E-ISSN 1758-6844, Vol. 26, no 3, p. 242-255Article in journal (Refereed)
    Abstract [en]

    Purpose - Water damage is a severe problem in modern construction, causing economic loss and health implications. The patented Air Gap Method, which is a slight modification of the common infill wall construction, provides means to build houses in a more robust way, minimizing the negative effects of water damage. This full-scale study of the method aims to show how walls and floors may be built to create ventilation within the construction, with air gaps equipped with heating cables. The general hypothesis is that the patented Air Gap Method drains and evaporates dampness after water damage. The purpose of this study is to show how the method is built and how the method deals with water damage, such as a flooding, and with mould growth. Design/methodology/approach - The Air Gap Method is based on a common timber-framed construction and is completed by the provision of inlets, air gaps, slits, and outlets. The power for the convective airflow is given by an electrical heating cable. The study was carried out as a full-scale experiment using a 24m2 large apartment build by this method. This apartment was flooded with 120 litres of domestic wastewater and the drying period was compared when heating cables were switched on or not. Mould growth was also investigated. Findings - The method dries out a flooded floor in nine days when two heating cables were switched on, in 13 days with one heating cable and 21 days when the heating cables were off. The method prevents all mould growth provided that the indoor RH is lower than 65 per cent. Practical implications - The method provides means to build houses in a more robust way, minimizing the negative effects of water damage. Originality/value - The issue of ventilated construction is rarely investigated in scientific research.

  • 42.
    Afkari, Arash
    Halmstad University, School of Business and Engineering (SET).
    Sustainable Low-Cost Housing in Ethiopia: A Study of CSSB-Technology2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project is about sustainable low-cost housing in Ethiopia with a focus on CSSB-technology, which is one method of constructing houses. The project allowed me to visit Ethiopia during seven weeks in 2010, to observe, gather information and to perform tests regarding the specific subject. It is a sub-project to a larger research project initiated in 2002 at Halmstad University in an attempt to introduce low-cost housing technologies for the Kambaata Region in Ethiopia. The aim of the research project has been to develop and test new, sustainable, low-cost building technologies intended for the population, with regard to local traditions, needs and affordability.

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  • 43.
    Afza, Zukhrook
    Jönköping University, School of Engineering, JTH, Civil Engineering and Lighting Science.
    Förstå BIM acceptans i ett utvecklingsland sammanhang: Fallet med Bangladesh's första BIM konsultverksamhet2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • 44.
    Agardh, Ella
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Jämförelse av kostnad och klimatpåverkan för olika typer av bjälklag och bärande innerväggar2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Byggnadsdelar av hållbara material är viktigt för att uppnå de miljömål som satts upp för Agenda 2030 samt för att skapa ett mer hållbart samhälle. För att bidra till detta analyserades och jämfördes olika uppbyggnader av bjälklag och innerväggar tillverkade av trä. Byggnadsdelarna ska uppnå de tekniska kraven som ställs och hur de olika skiljer sig i kostnad och CO2e-utsläpp vid olika spännvidder och laster. Bjälklagen och innerväggarnas olika materialskikt kontrollerades för att undersöka vilket skikt som bidrar med det högsta utsläppet, för att göra det möjligt att utveckla materialet i framtiden. En jämförelse utfördes för bjälklagen tillverkade av korslamminerat trä och betonghåldäckets kostnad och undersöka om användningen av träbjälklaget blir mer lönsamt. 

    Arbetet utgick ifrån fyra alternativa typer av bjälklag och två typer av bärande innerväggar till en skolbyggnad som Sweco ansåg intressanta att utvärdera. Utformningen på dessa bjälklag och väggar bestämdes i detalj genom val av materialskikt för att uppfylla de tekniska kraven och dimensionering av de bärande delarna i konstruktionerna. För bjälklagen dimensionerades stommen utifrån spännvidder mellan 4–12 meter och väggarna dimensionerades utifrån antagandet att skolbyggnaden bestod av fyra våningsplan. Efter att detaljutformningen bestämts beräknades materialvolymerna som sedan låg till grund för kostnadsberäkning och klimatpåverkan. Det fyra bjälklagstyperna var baserade på KL-trä, limträ, lättbalk och betonghåldäck som bärande konstruktion för skolbyggnaden medan de två väggtyperna konstruerades av KL-trä och reglar.

    Resultatet bidrar till att undersöka vilken stomme som är mest effektiv utifrån ett kostnads och klimatperspektiv samt ge ökad kunskap om trästommars egenskaper. Jämförelsen visar att bjälklagen tillverkade i trä är mer gynnsamt ur ett klimatperspektiv för alla träbjälklag medan kostnaden varierar beroende på vilket träbjälklag som kontrollerades. Genom att undersöka kostnaden utifrån ett framtidsperspektiv kan trästommar vara mer lönsamt. För bjälklagen var limträbalken fördelaktigast för kostnaden för alla spännvidder. KL-trät var dock mest gynnsam utifrån utsläppet för spännvidderna 4–8 meter medan lättbalken hade det högsta utsläppet. För innerväggarna var kostnaden högst för KL-trät men hade det lägsta utsläppet upp till tre våningar därefter hade regelstommen ett lägre utsläpp. 

    De slutsatser som kan dras utifrån arbetet är att trästommar är mer lönsamt ur ett hållbarhetsperspektiv dock har trä en relativt hög kostnad i dagsläget. Limträbjälklaget och regelväggen har en relativ låg kostnad i jämförelse med de andra och ett lågt utsläpp som skulle kunna användas för att bidra till de uppsatta klimatmålen. En minskad kostnad av trä skulle göra att respektive träbjälklag är mer lönsamma utifrån både kostnaden och klimatet i jämförelse med betong. 

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  • 45.
    Agebro, Andreas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Datormodellering av en värmelagrande betongväggs inverkan på det termiska klimatet i ett växthus2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes the building of a computer model that makes it possible to simulate the thermal climate in a greenhouse. The computer model is built on the physical theory of heat exchange that occur in a greenhouse, such as radiation and convective heat exchange. The model also includes the heat storage that is active in a greenhouse.

    The computer model is used to simulate the thermal climate in a greenhouse under three periods, winter, spring and summer. It also investigates which effect a concrete wall has on the thermal climate in a greenhouse. The purpose of putting a concrete wall in the greenhouse model is to investigate the possibility to store heat during the day and then use this heat when the temperature drops during the night.

    The result from the simulations shows that a concrete wall levels the big difference in temperature that normally occurs under a day in a greenhouse. It also shows that heat is stored in the concrete wall and during the night the wall temperature is higher than both the outdoor temperature and the greenhouse temperature. This makes the wall a source of heat during this time.

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  • 46.
    Ageby, Oscar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Sher, Nardin
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Bjälklagselement i håldäck och korslimmat trä: En jämförelsestudie mellan två bjälklagselement2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In society today, the focus is on sustainability, which places high demands on the designer when designing the structural frame for apartment buildings. A large part of the CO2 emissions in the construction process can be traced to the choice of material, where the combustion of lime in the cement industry and the production of steel from iron ore are among the main factors for the emissions.

    This report intends to provide answers to the differences and similarities between two frame systems with different floors slabs; a version in cross-laminated wood, hereinafter referred to as KL-trä (CLTwood), and a version in hollow core slabs. The two objects have been given identical conditions, with a reservation for flooring material, with a steel frame with varying cross-sectional profiles.

    Data for CO2 equivalents and price of each frame material have been examined and compiled in tabular form where the two buildings are evaluated and results are discussed in the analysis part. The result provides an answer as to which element performs best for an office building with two floors with regard to cost and CO2 equivalents for individual profiles compiled for the two buildings.

    Dimensioning of beams has been carried out with regard to bending moment capacity, columns with respect to buckling of concentric pressure force and flat bending buckling with elements of wind load and normal force against columns. Tekla Structures has been used to visualize the frame and FEM-Design20 has been used to verify load counts.

    The financial part of the report refers to costs of the two buildings, which are reported in tabular form with cost per steel and floor profile. The lump sum for each case has been compiled and in the discussion section of this report explanations and conclusions are given to the financial part.

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  • 47.
    Agnesson, Stina
    et al.
    Jönköping University, School of Engineering, JTH, Civil Engineering.
    Bagger-Sjöbäck, Josefina
    Jönköping University, School of Engineering, JTH, Civil Engineering.
    PREFABRICERADE SMÅHUS PLANLÖSNINGAR: En jämförelse mellan tillverkare och kund2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med arbetet är att analysera utformningen av planlösningarna i prefabricerade småhus. Resultatet ska kunna utnyttjas som underlag vid planlösningsutformning och möjliggöra planlösningar med färre kundändringar.  

    Metoder som används är litteraturstudier, intervjuer och en fallstudie. Fallstudien är gjord med material från företaget Anebyhus som tillverkar prefabricerade småhus. Ur en av deras kataloger valdes tre olika hus med snarlika förutsättningar. Det som analyseras är tillverkares och kunders prioriteringar samt de vanligaste kundändringarna. Problemet är att om kunden ska bli nöjd med den slutliga planlösningen måste kunden och tillverkaren ha liknande kvalitetsprioriteringar. Ändringar som återkommer frekvent är ett tecken på en svaghet i ursprungsplanlösningen.

    Resultaten visar att tillverkare av prefabricerade småhus möter kundernas behov och önskemål genom prioriteringar av livslångtboende och flexibilitet i planlösningen. Kunderna visar prioritering av mer bänkytor i köket, vardagsrummet storlek och samband till köket och att alla i familjen ska få varsitt sovrum. De kundändringar som förekommer mest frekvent är minskning av antalet klädkammare, sammanslagning av teknik och klädvård samt att ändra till en U-formad köksuppställning. 

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  • 48.
    Agredo Chávez, Angélica
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Gonzalez-Libreros, Jaime
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Wang, Chao
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Capacci, Luca
    Department of Civil and Environmental Engineering, Politecnico di Milano, Milan, Italy.
    Biondini, Fabio
    Department of Civil and Environmental Engineering, Politecnico di Milano, Milan, Italy.
    Elfgren, Lennart
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Sas, Gabriel
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Assessment of residual prestress in existing concrete bridges: The Kalix bridge2024In: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 311, article id 118194Article in journal (Refereed)
    Abstract [en]

    The direct socio-economic consequences of the deterioration of aging infrastructure systems have triggered a continuous process of revising and updating current design standards and guidelines for critical network components. Specifically, long-term degradation processes demand the analysis and evaluation of vital structural assets such as prestressed concrete bridges. It is crucial to develop theoretically consistent, user-friendly, and non-destructive methodologies that engineering professionals can employ to prevent and mitigate potential catastrophic outcomes during the service life of these bridges. This study provides a thorough review of the available testing methods employed over the years for prestressed concrete bridges and introduces a comprehensive framework for evaluating existing methods for residual prestress force assessment. Through a multi-criteria selection process, the three most feasible tests were designed and carried out on an existing 66-year-old balanced cantilever box girder bridge exposed to freezing temperatures that affected the instrumentation plan and test execution. Finally, predictive models compliant with standard codes were calibrated based on the experimental results and the life cycle loss of prestress forces was evaluated to assess relevant bounding intervals. Findings reveal limited on-site testing and discrepancies between calculated residual forces and predictions by standard codes. The saw cut method showed a 18% difference from the initial applied prestress according to the prestress protocol, suggesting the use of a cover meter and concrete modulus evaluation for improved accuracy. The strand cutting method resulted in a 14% difference, emphasizing the need for stress redistribution assessment. The second-order deflection method showed a 6% difference, indicating a focus on enhanced boundary conditions and thorough sensitivity analysis for future investigations.

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  • 49.
    Agriam, Pia
    Jönköping University, School of Engineering, JTH, Civil Engineering.
    Socialt hållbart boende2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    We need more research about what gives man good conditions for quality of life in a home environment. Social sustainability is a topic that is cherished more than ever in the world of architectures. The goal is to develop a knowledge base based on the experiences of users, architects and clients that can be used for the design of residential areas with apartment buildings.

    To achieve the goal there are questions to be answered as: "How is socially sustainable housing valued, according to architects and clients, when residential areas with apartment buildings are designed?" and "How are the values of social sustainability perceived, in residential areas with newly constructed apartment buildings, of the residents?" The questions are answered by means of an survey and several of interviews which together constitute a qualitative research.

    The results show that social sustainability can be seen from different angles. It is common to observe social sustainability from a community perspective and from an urban perspective according to scientific references. As an overall summary it is the beautiful shape and appearance of a building and its functionality weighed in with a reasonable cost that creates a socially sustainable housing according to interviews with architects and clients. It is about balance between beauty, functionality and economy, which together create a housing that lasts over time and confirms the human social dignity. According to those living in the area of Nysäter in Mölnlycke as the studied phenomenon, socially sustainable housing stands for comfort, security, privacy and community. Access to nature and outdoor activities, fresh air and good neighbourship are other factors that are highly valued. Socially sustainable housing has therefore connections to both physical parameters as well as non-physical qualities that needs to be linked with each other.

    The summarized results highlight the essential aspects that should be included in the planning of a new residential complex for it to be socially sustainable for residents. The knowledge base has a logical order from analyzing an unspoilt area with its qualities to analyze how the private residence must meet human needs for well-being.

    The Report is wide in its choice of subject tough it is limited to man's relationship to the dwelling and residential area in social contexts, how individuals perceive their environment both in and outside their home. With additional constraints had a deeper research been able to implement on a specific theme.

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  • 50.
    Ahaki Lakeh, Amir
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Tahmasbi, Milad
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Life cycle assessment and structural analysis of renovation of Ulriksberg school building in Växjö2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Massive volumes of hazardous emissions have been produced by the construction sector for which some adequate steps are implemented, but the rising trend of emissions can still be seen. In this thesis, the goal is to identify and analyze renovation measures from primary energy use and environmental impacts perspective, according to Boverket’s mandatory provisions and general recommendations (BBR 2018), for an old school building. Also, as a part of the study goal, the building structure is analyzed under the updated Eurocode SS-EN 90-91-96 in order to see if the building meets structural stability requirements. Life cycle assessment of the building is limited to production and construction stages, and it is used as a tool to evaluate the environmental impacts according to standard SS-EN 15978:2011. Most of the relevant data are provided by VÖFAB, in cooperation with Växjö municipality, as well as the company WSP group.

    The object of the thesis is an old three-story school building constructed in 1950 in Växjö, Sweden. The gross area of the building is 1,300 m2 and for renovation scenarios, building envelope components are investigated by adding new insulation materials considering two life cycle stages. In the production phase, the lowest primary energy use was 137 kWh/m2 for the scenario of using cellulose insulation material plus windows and exterior doors with a U-value of 1.1 [W/m2 K]. The lowest environmental impacts were also obtained for this scenario, with 14 kg CO2-eq/m2 global warming potential (GWP), 0.06 kg SO2-eq/m2 acidification potential (AP), and 0.06 kg NO3-eq/m2 eutrophication potential (EP). The results indicate that the share of the installation step in the primary energy use and environmental impacts during the construction phase is negligible, but the transportation role in this stage is significant. The highest global warming potential is for the scenario using cellulose insulation material plus windows and exterior doors with a U-value of 0.7 [W/m2 K] with 4.4 kg CO2-eq/m2 in the construction stage. Ultimately, the material production stage accounts for the most share of primary energy use and environmental impacts. 

    This research provides several renovation measures investigated by life cycle assessment resulting in performing climate declarations. Regarding the sensitivity analysis, the electricity source has a considerable effect on reducing total primary energy consumption and environmental impacts during the production phase. It is also found that the scenario utilizing cellulose insulation material with windows with a U-value of 1.1 [W/m2 K] shows the lowest total primary energy use and environmental impacts. Through analyzing the building structure, all Eurocode criteria within the serviceability limit state (SLS) and ultimate limit state (ULS) are fulfilled, and the structure is still stable when new materials are added through renovation.

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