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  • 251.
    Lemaitre, Romain
    et al.
    ENSTIB/LERMAB, University of Lorraine, France.
    Bocquet, Jean-Francois
    ENSTIB/LERMAB, University of Lorraine, France.
    Schweigler, Michael
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bader, Thomas K.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Beam-on-foundation modelling as an alternative design method for timber joints with dowel-type fasteners: Part 1: Strength and stiffness per shear plane of single-fastener joints.2018In: 5th INTER Proceedings, 2018: International Network on Timber Engineering Research 2018, Karlsruher Institut für Technologie , 2018, article id 51-7-13Conference paper (Refereed)
    Abstract [en]

    Optimised manufacturing processes made possible the production of larger dimensions timber products, which allow for the design of remarkable structures. In the last version of the EN 1995-1-1, it seemed important to its drafters to propose design formulas to estimate stiffness of joints in accordance with the needs of that time. Aware of the technical jump that had to be managed, the proposed rules remained simple. However, simple design equations became insufficient to cope with present-day challenges, which are, e.g., related to the design of high-rise wooden buildings. In EN 1995-1-1, the resistant capacity of dowel-type timber joints is no longer determined by empirical formulas but it is based on the limit analysis proposed by Johansen (1949). This methodology however shows limits for complex joints even though many improvements have been made since its introduction (Blaß and Laskewitz 2000). In parallel with these analytical approaches, developments in computational mechanics made it possible to develop simple numerical methods (Foschi 1974, Hirai 1983), which taken even into account nonlinear phenomena. These approaches have remained unused in practical design due to their complex implementation and their high running time, at the time of their invention, while todays computational resources strongly reduced corresponding limitations. Thus, numerical modelling of connections can help engineers to fill the gaps of the EN 1995-1-1 and to cope with variability in connection design. For this purpose, dowel-type fasteners are numerically modelled as elastoplastic beams on a nonlinear foundation in engineered in wood-based products (Sawata and Yasumura 2003, Hochreiner et al. 2013). This method is called Beam-On-Foundation (BOF) modelling and shows huge potential for engineering design. The purpose of this paper is to show how this method can substitute and complement limit analysis and empirical stiffness formulas of timber joints with dowel-type fasteners.

  • 252.
    Lemaitre, Romain
    et al.
    University of Lorraine, France.
    Bocquet, Jean-Francois
    University of Lorraine, France.
    Schweigler, Michael
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bader, Thomas K.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Beam-on-Foundation Modelling as an Alternative Design Method for Timber Joints with Dowel-Type Fasteners: Part 2: Modelling Techniques for Multiple Fastener Connections2019In: INTER: International Network on Timber Engineering Research: Proceedings, Meeting 52, 26-29 August 2019, Tacoma, USA, Karlsruhe, Germany: Timber Scientific Publishing, KIT Holzbau und Baukonstruktionen , 2019, article id 52-7-9Conference paper (Refereed)
    Abstract [en]

    In many design codes for timber structures (e.g. Eurocode 5 and SIA 265), the stiffness of a connection is given by empirical equations for a single dowel-type fastener per shear plane. The global stiffness of the connection is then given by multiplication with the number of dowels and shear planes. In the codes cited above, the empirical equations to estimate stiffness only depend on two parameters, namely the dowel diameter and the wood density. The main difference between different codes and stiffness of different types of fasteners is the choice of the exponent on these two parameters. Development and background of empirical equations for stiffness in different codes were recently reported in Jockwer and Jorissen (2018), who analysed about one thousand double shear timber-to-timber connection tests to evaluate the influence of further parameters on stiffness, such as number of fasteners in a row, number of rows of fasteners and dowel slenderness. From this huge database, they have been able to estimate another empirical stiffness equation, that includes dowel slenderness as an additional parameter. Effects of the latter have even been reported in Lemaître et al. (2018), by using a phenomenological numerical model instead ofexperiments. Sandhaas and van de Kuilen (2017) reported that using the slip modulus Kser, calculated according to Eurocode 5 for stiffness prediction of multiple fastener joints, considerably overestimates the experimentally observed stiffness and they proposed to introduce an effective number of dowels in their design, which was also recommended in Jockwer and Jorissen (2018).

    This paper continues the work presented in Lemaître et al. (2018) on strength and stiffness estimations of single-fastener connections using a beam-on-foundation (BOF) modelling. In Lemaître et al (2018), the beam-on-foundation model calculations were compared to design equations of Eurocode 5, i.e. the load-carrying capacity and slip modulus. By these comparisons, the validity of the method for the design of single-fastener connections was highlighted. Moreover, effects that are not explicitly covered in the empirical design equations, namely the influence of the dowel slenderness and the nonlinear dowel diameter on the slip modulus were demonstrated.

    In the present paper, the same comparisons are made for multiple dowelled connections. Moreover, load distribution between dowels in this type of connection, which was shown to be non-uniform by Blass (1995), is studied by means of the BOF model. Different approaches to estimate the load distribution have been proposed by Cramer (1968), Lantos (1969) and Wilkinson (1986).

  • 253.
    Lindblad, Fredrik
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Bolmsvik, Åsa
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Pettersson, Jenny
    Wiberg, Sara
    Efficiencies in the On-Site Material Handling Process by Using Radio Frequency Identification in the Wood Building Construction Industry2018In: International Journal of Innovation, Management and Technology, ISSN 2010-0248, Vol. 9, no 6, p. 252-259Article in journal (Refereed)
    Abstract [en]

    In the past decades, the housing shortage in Sweden accumulated to a level that led to problems finding accommodation for many people, which created opportunities for the market producing multi-family houses. The market is dominated by concrete solutions whereas solutions using wood as a building material only comprise 9 % of the market. This market is highly competitive with many companies offering relatively similar products or services. One way to develop new business opportunities is to enhance other competence besides production technology that currently acts as a market development barrier. Hence, the material handling process at building sites is seen as a barrier that can contribute improving competitiveness.

    There are currently problems with material handling at many building sites of wood-building solutions in Sweden, materials arrive at the wrong time, waste of storage space, unnecessary tracking of materials or wrong quantities arriving at the sites. The purpose of the study is to investigate if Radio Frequency Identification (RFID) is a technology that can be used to achieve an efficient material handling process and if the wood building industry in Sweden is willing to implement the technology. Thus, investigate if material handling using RFID can improve time effectiveness, minimise waste and monitor moisture levels in the material efficiently, creating improved competitiveness. The study shows that the use of RFID improves time efficiency and control the material handling, indicating that RFID has potential to improve this process. Further, the study identifies possibilities by using RFID technology to minimize damages and control moisture levels.

  • 254.
    Lindblad, Fredrik
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Magnusson, Bengt
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Luu, Alan
    Ragnarsson, John
    Information Flow Optimisation: Enabling Standardisation towards Modular Building Methods of Wood-Building Solutions2018In: International Journal of Innovation, Management and Technology, ISSN 2010-0248, Vol. 9, no 6, p. 232-239Article in journal (Refereed)
    Abstract [en]

    Currently, there is a considerable lack of residential buildings in Sweden. Hence, companies that are active in the housing industry producing wood-building solutions have been affected by high demand for their products. The industry tries to be more effective, and one means of achieving this goal is to automate the production, similar to the automotive industry. However, improvements in the information flow have not come as far as developments in the production. Therefore, it is necessary to streamline the entire process and reduce the amount of manual work using rationalisation and automation to enhance competitiveness. This is not only applicable to the actual manufacturing process but also in a large degree to the design process, i.e. the transition from the basic to the detail design stage. The purpose of this research is to compare the information flow for various building projects before production, identifying development possibilities by using an improved information process.

    Information has been collected into a status report using interviews, surveys and from data in the Enterprise Resource Planning (ERP) system.

    Two areas were identified out of the status report: standard projects and special projects. The special projects constitute 90 % of the project departments actual workload, whereas standard projects do not exceed the projected lead times creating less problem than special projects. Therefore, the long-term development strategy for the industry should be to improve the level of project standardisation, developing an advanced modular system based on improved information flow minimising the need for special projects.

  • 255.
    Lindblom, Mikael
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Toll, Lucas
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Dimensionering av infästningsplåtar i prefabricerade betongelement - viktiga parametrar2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Arbetet går ut på att för Nybro Cementgjuteri utföra dimensioneringsberäkningar för infästningsplåtar ingjutna i prefabricerade betongelement. Genom att utföra dessa beräkningar har ett beräkningsunderlag i Microsoft Excel kunnat framställas och levereras till företaget. I underlaget kan företaget föra in olika plåtparametrar som bredd, höjd och tjocklek på plåten samt förankringsstängernas längd och tjocklek med mera och få ut vilka kapaciteter plåtarna besitter gällande normalkraft, tvärkraft samt moment i tre olika riktningar.

    Dessutom har en parameterstudie utförts där det har undersökts vilka konsekvenser det skulle medföra att till exempel ändra avståndet mellan förankringsstängerna.

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  • 256.
    Lindell, Emma
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Gröna tak och växtväggar - förutsättningar och effekter2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bruket att täcka in tak och väggar med växtlighet är något som ökar mer och mer. Klimatförändringar tvingar oss att förändra vårt förhållningssätt till naturen och tänka mer klimatsmart. Vidare skapar de hårdgjorda ytor som dominerar i städer problem med avrinning av regnvatten samt lokalt varmare miljöer som inte förekommer naturligt. Gröna tak och växtväggar skulle kunna vara en del av lösningen på dessa problem. Det här arbetet svarar på vilka typer av olika gröna tak och växtväggar som finns tillgängliga idag i Sverige samt vilken typ av grönt tak som går att använda vid olika sorters takläggning. Det undersöktes även hur gröna tak och växtväggar påverkar omgivningen och klimatet, lokalt och i viss mån globalt. Arbetet tar också upp hur vi människor påverkas av att ha gröna tak och växtväggar i den urbana miljön.

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  • 257.
    Linder, Ludvig
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Analytisk implementering av 4D projektering2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The building sector is in need of enhanced efficiency. The methodology behind Building Information Modeling, BIM, which is being used increasingly in extent, has shown to improve the efficiency of the flow of information in projects. The concept of 4D is based on the working method and methodology of integration between BIM and a time schedule. This can under certain circumstances further improve the efficiency of the planning phase of building- and civil engineering projects. Today there are not many companies that have begun to use this method and methodology, even though it has been shown to be effective for some conditions. This report addresses this dilemma, why and how companies can implement the work and process of 4D. 

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  • 258.
    Lindfors, Hampus
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Cedmert, Philip
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Digital energistyrning av lägenheter - Är det lönsamt?2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Äldre flerbostadshus i dagens Sverige använder sig av väldigt mycket energi i onödan. Uppvidingehus är ett fastighetsbolag som anser att deras flerbostadshus har en hög energianvändning. Tre områden i Åseda granskas under denna studie för att se ifall ett digitalt energistyrningssystem kan förminska energianvändningen på dessa områden. Resultatet redovisar vilka byggnader som skulle kunna uppnå en lägre energianvändning och ifall det är lönsamt för ett mindre bostadsföretag att investera i ett digitalt energistyrningssystem.

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  • 259.
    Lindmark, Filip
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Vestholm, Adam
    Potentialen i stadens överblivna ytor2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bostadsbristen är ett problem  som sträcker sig över hela landet. Platser för bebyggelse i städerna minskar.  Arbetet undersöker tre platser i Stockholm för framtida bebyggelse. Rapporten behandlar problem som dycker upp vid förtätning av Sveriges storstäder.

    Sverige har en lång historia gällande stadsbyggnad där olika ideal har format städerna under åren. Sveriges storstäder begränsas när det gäller platser som behövs för framtida bostäder. Nya metoder undersöks för att skapa ny mark att bebygga och en av platserna som behandlas i arbetet planeras en överdäckning. Platserna som behandlas i arbetet ligger på Lilla Essingen, överdäckning av Fredhällstunneln och östra delen av Södermalm.

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  • 260.
    Lindstam, Gustaf
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Larsson, Beatrice
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Optimized utilization of raw materials for production of Cross Laminated Timber: Quality of laminations and its effects on mechanical properties of multi-layer panels2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Cross laminated timber (CLT) is a product increasingly demanded by the market. This has led to an interest among producers to further optimize the use of raw material. The aim of this investigation is therefore to analyze how the material properties in softwood lamellas, when used in different layers of a CLT plate, affect the stiffness and strength for CLT floor elements. This is done by analysis of CLT constructions with different dimensions, constructions and quality of lamellas. For the bending stiffness of CLT plates, the most important lamination property is the longitudinal modulus of elasticity. However, the stiffness to rolling shear of the lamellas has also large influence on the combined bending and shear stiffness of a CLT plate. The properties for the lamellas that has being used in this investigation are valid for Norway spruce (Picea Abies .L). For investigation and analysis of the lamellas and the CLT floors has Finite Element simulations by the software Abaqus (2017) along with hand calculations been used. A total of three different simulations were performed to accomplish the objectives set in this work.

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    bilaga
  • 261.
    Lindström, Lisa
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Lätt, Julia
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Vad är en tillgänglig bostad?: En studie om funktionsanpassning i en bostad2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Många människor lever idag med någon form av rörelsenedsättning. Att planera en bostad bör till stor del handla om tillgänglighet och användbarhet där alla människor ska kunna leva på lika villkor oavsett behov. Det här arbetet undersöker om de lagar och regler som redan finns angående tillgänglighetsanpassning är tillräckliga och vad som krävs utöver detta med fokus på entré, badrum, kök samt brukarens sovrum. 

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  • 262.
    Lovén, Joacim
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kallay, Viktor
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Utredning av byggavfall och ställtider2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studien har undersökt Botrygg ABs ställtider och uppkomsten av byggavfall. Målet har varit att optimera ställtiderna och minimera byggavfallet. Metoderna som ansågs vara lämpligast för studien var intervjuer, framtagning av statistik samt observationer. Detta genomfördes på två av Botrygg ABs byggarbetsplatser med specifikt fokus på platsen Kv. Duvkullen. Intervjupersonerna representerade inköp, logistik, plats -och byggchef. De uppnådda resultaten sett till olika moment i avfallshantering och planering mot ställtider gav möjlighet att dra slutsatser mot vad Botrygg AB kan göra för möjliga ändringar för en förbättrad produktion sett till kostnader, tidseffektivisering och ge en reducerad miljöpåverkan. Framtagna resultat är statistik av byggavfallet vid en av byggarbetsplatserna, intervjupersonernas resonemang och åsikter kring de två berörda frågor, sett till vad som kan göras bättre samt vad som i nuläget fungerar. Dessa resultat jämfördes och följande slutsatser kunde dras:

    • närmare samarbete med leverantörer,
    • vidareutveckla Just-in-time,
    • kontinuerlig kommunikation mellan berörda aktörer,
    • uppföljningar av projektens byggavfall för att se vad som genereras,
    • sätt upp ett tydligt mål om mängder byggavfall genom att t.ex. använda statistik.
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  • 263.
    Lowentoft, Carolina
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Vändal, Susanna
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Utvärdering av Portvakten Söders spillvattenvärmeväxlare och varmvattenförbrukning2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    År 2009 färdigställdes två passivhus på Portvakten Söder i Växjö. Mellan de två byggnaderna finns en spillvattenvärmeväxlare installerad i ett försök att ta tillvara på outnyttjad energi ifrån byggnadernas utgående spillvatten. Växlarens effektivitet undersöks genom beräkning av dess temperaturverkningsgrad över ett dygn. Verkningsgraden bestäms genom temperaturmätning med tekniken termoelement. Vald metod tillsammans med upptäckten av grundvatten på mätplatsen medförde att temperaturmätningen inte blev tillförlitlig och uträknad verkningsgrad för växlaren blev därmed inte rimlig.

    Under 2013 var skillnaden i varmvattenförbrukning 55 % mellan de två husen. En enkät utformades med syfte att utreda skillnaden i varmvattenanvändningen. Resultatet av enkätundersökningen jämförs mot verklig varmvattenförbrukning under år 2013.

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    Utvärdering av Portvakten Söders spillvattenvärmeväxlare och varmvattenförbrukning
  • 264.
    Lukacevic, Markus
    et al.
    Vienna University of Technology, Austria.
    Kandler, Georg
    Vienna University of Technology, Austria;Dynardo Austria GmbH, Austria.
    Hu, Min
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Olsson, Anders
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Füssl, Josef
    Vienna University of Technology, Austria.
    A 3D model for knots and related fiber deviations in sawn timber for prediction of mechanical properties of boards2019In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 166, p. 1-18, article id 107617Article in journal (Refereed)
    Abstract [en]

    Increased use of wood has led to complex timber constructions and new types of engineered wood products. In simulations, however, mainly simplified models are used to describe this material with its strongly varying properties. Therefore, reliable prediction tools for mechanical properties of wooden boards are needed. Those varying properties mainly originate from knots and fiber deviations. Thus, we use fiber directions on board surfaces to reconstruct knots within boards. Combined with a fiber deviation model we assess our model with experiments on different levels: fiber directions on surfaces, strain fields and bending stiffness profiles.

    This model now better describes fiber patterns near knots and knot clusters. Also, we showed that accurate modeling of the pith is important to avoid large regions of incorrect fiber deviations. Furthermore, modified knot stiffness properties were successfully used to consider pre-cracked knots. Finally, we obtained multiple bending stiffness profiles, where we showed that even local effects can be simulated accurately.

    We anticipate our tool to be a starting point for improving strength grading models, where effects of knot configurations can be studied more easily than with experiments alone. Furthermore, the presented improvements will render the simulation of realistic failure mechanisms in wooden boards more likely.

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  • 265.
    Lundström, Alice
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Karlsson, Adrian
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Att skapa ett attraktivt stadsrum2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Städer i Sverige utvecklas ständigt och samhällsplanerarna ställs inför nya utmaningar. Utvecklingen av dagens moderna städer formas av utmaningen att uppnå EU:s hållbarhetsprinciper. Detta ska göras genom att tillfredsställa dagens behov utan att äventyra kommande generationers möjlighet att tillfredsställa sina. En stad som anses vara hållbar kännetecknas av att planeringen och byggandet sker efter ett långsiktigt mål för ett beständigt samhälle. Det hållbara samhället präglas av trivsamma miljöer som skapar mänsklig närvaro. För att detta skall uppnås måste stadsrummet upplevas som attraktivt. Det attraktiva värdet har en betydande roll i arbetet och strävan i skapandet av hållbara städer. I följande rapport undersöks vilka arkitektoniska attribut som anses vara attraktiva i stadsmiljöer samt vilka attribut som upplevs ha en positiv inverkan på människan. Undersökningen baseras på datainsamling från en enkät, intervjuer och platsobservationer. Resultatet redovisar information om vilka arkitektoniska kvalitéer som människan anser som attraktiva, de utmaningar och svårigheter som uppstår i ett stadsutvecklingsprojekt samt vilka kvalitéer som kännetecknar en stads identitet. Den insamlade informationen användes som grund för framtagandet av ett visuellt förslag av utveckling för Brädholmen i Oskarshamns inre hamn. Ett attraktivt stadsrum innefattas av relationen mellan byggnadernas variation, originalitet, småskalighet, kulörrikedom och historiska komponenter. Stadsrummet bör kännetecknas av tre samverkande faktorer, byggnaders estetiska utförande, mänsklig rörelse och landskapets kvalitéer.

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  • 266.
    Lundström, Fredrik
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Utvärdering av miljön i området Torparängen med laserskanning2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Rapportens syfte är att få reda på om utvändig laserskanning av en byggnad är en lämplig metod att använda för byggbranschen. En laserskanning kommer göras av torpet Furutå, i området Toparängen, som ligger i Växjö.

    Laserskanningen har gjorts genom att tre uppställningar med skannern har genomförts. Denna data sammanfogas sedan i programmet Leica Cyclone. Sedan bearbetas modellen i Autodesk Recap och AutoCAD. Här skapas sedan 2D-ritningar av fasader och även en 3D-modell. Laserskanningen kommer även georefereras, vilket innebär att modellen flyttas från ett lokalt koordinatsystem till svenska referenssystemet SWEREF99. Studien visar på att laserskanning har ett brett användningsområde och med tillräckligt låg mätosäkerhet.

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  • 267.
    Mahapatra, Krushna
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Johansson, Martina
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Petersson, Johanna
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Enviromental implications of Växjö municipality’s energy requirement for new residential buildings2014In: Energy Procedia: INTERNATIONAL CONFERENCE ON APPLIED ENERGY, ICAE2014 / [ed] Yan, J; Lee, DJ; Chou, SK; Desideri, U; Li, H, Elsevier, 2014, Vol. 61, p. 411-414Conference paper (Refereed)
    Abstract [en]

    The Växjö Municipality in Sweden sets specific energy requirements above the national building code while sellingland for new residential buildings. A main energy requirement for Östra Lugnet residential area in Växjö was that allbuildings must be connected to the district heating network. In this paper we analysed final energy use of thebuildings, and compared the primary energy use and CO2 emission from operation of the buildings connected todistrict heating system with hypothetical scenarios where only air-source heat pumps were installed. The resultshowed that district heating is the better option from the perspective of lower carbon emission. Therefore, it seemsappropriate for Växjö Municipality to set conditions for new residential buildings in Östra Lugnet to connect to thelocal district heating network as it contributes to its goal of low carbon society.

  • 268.
    Malmgren, Sebastian
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Thiel, Olivia
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Måste dörren stängas till din framtida arbetsplats?2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Allt fler anställda runt om i landet väljer att ta med sig arbetet hem för att sitta och jobba i en hemmamiljö istället för att ta sig till företagets egna lokaler. Varför? Vem arbetar bäst bakom stängda dörrar? Hur ska ett företag tänka kring sin arbetsmiljö för de anställda? Det är några av de frågor som rapporten tar upp och diskuterar för att få svar på den universella frågan:

    “Måste dörren stängas till din framtida arbetsplats?”  

    De kontorsmiljöer som tas upp i rapporten är cellkontor, ABW-kontor och kombikontor. Dem tre jämförs och behandlas genom tre aspekter som är socialt, arbetseffektivt och hållbart perspektiv. Även den personliga arbetsytan tas upp och diskuteras, hur den påverkar den anställda men också organisationen i stort. Rapporten fungerar som en riktlinje för både Linnéuniversitetet och andra företag som vill utveckla eller förnya sina respektive arbetsmiljöer. Rapporten lyfter fram för- och nackdelar av de tre kontorsmiljöerna (cellkontor, ABW-kontor och kombikontor) som undersöks och ger förslag på vilka arbetsmoment som bäst lämpar sig i de olika miljöerna.

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    Måste dörren stängas till din framtida arbetsplats?
  • 269.
    Mattsson, Johan
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Anton, Vestesson
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Moderna tillgänglighetsanpassningar för ett bekvämare åldrande2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Vid nyproduktion av bostadshus är det viktigt att inte glömma bort den äldre målgruppen och dess behov när det kommer till design, utformning och funktion. Den äldre målgruppen utgör en stor del av vårt samhälle och det här arbetet redovisar tydliga riktlinjer på hur bostadshus ska anpassas för att göra de användbara och tillgängliga för personer med nedsatt rörelseförmåga.

    Alla rum i ett bostadshus behandlas med fokus på badrum/tvätt, kök och entré/hall. 

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  • 270.
    Merlo García, Ramón
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Glass-fibre reinforcement on steel to timber connections.: A parametric study through FEM modelling on double-shear single-dowelled connections.2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In a context where timber is gaining popularity as a building material and glass-fibre reinforced composites (GFRC) are becoming more accessible in a wide variety of formats, it is considered appropriate to reconsider the combination of these two materials. Additionally, given the increasing use of laminated timber elements where stiffness and strength are better controlled, attention is drawn back to the connection between elements. For these reasons, it is considered of interest to study reinforcing possibilities for connections within timber structures.

    This work consists in a parametric study of a single-dowelled connection between a timber part and a slotted-in steel plate, reinforced wirh GFRC plates glued into the timber slot at both sides of the steel plate. The study was carried out through simulations in ABAAUS Finite Element Analysis software considering the effect of specimen's geometry and the fibre distribution within the GFRC.

    Results show the increase of stiffness for the different configurations and give an insight of what can be expected from such type of reinforcements.

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  • 271.
    Mmari, Winston
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Modeling of nailed timber connection: Displacement path dependency in sheathing-to-framing connections2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Connections in wood have been investigated and advanced ever since the ground-breaking work of Johansen in the early nineteenth century. Nevertheless, not much investigation has been undertaken on the existence of load-displacement path dependency in a sheathing-to-framing connection. Herein, a sheathing-to-framing connection is investigated in relation to displacement path dependency. This work uses 3D Finite Element beam-on-foundation models of an Oriented Strand Board (OSB/2) sheathing nailed to a C24 wood framing, to study possible strategies to numerically simulate the displacement path dependency. The models are used to study if non-linear elastic or elastic-plastic embedment properties of an annular-ringed shank nail in the wood-based materials bring about the path dependency using Connector elements in combination with different material models in the FE software Abaqus. Numerical results are compared with corresponding experimental test results of the connection together with the Eurocode 5 approach. The outcome of the numerical study both; confirms the existence of displacement path dependency and shows that this property in the connection can be described by plasticity properties in nail, sheathing material and the wood framing.

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  • 272.
    Moayed, Dena
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Ly, Nancy
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Marcuson, Anna
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Utemiljöer som främjar människors lika värde: Tillgänglighetsanpassning för personer med synnedsättning2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    FN har tagit fram regler kring främjandet av rättigheterna för personer med funktionsnedsättning. Detta innebär att allmänna platser och utemiljöer ska vara tillgängliga och användbara för alla. Målet med detta examensarbete är att ta fram typlösningar som är anpassade för personer med nedsatt orienteringsförmåga, med fokus på synnedsättning. Den geografiska avgränsningen är Östra Sjukhuset i Göteborg, men resultatets lösningar skall även vara applicerbara på andra allmänna utemiljöer.

    Lagar och rekommendationer har jämförts med brukarnas subjektiva upplevelser av utemiljöer för att se om eventuella glapp uppkommer. Av platsobservationerna och studier av lagar och bestämmelser kan det konstateras att strängare krav måste ställas vad gäller tillgänglighet. Att skapa en fungerande tillgänglig och användbar miljö kräver dock inte enbart att regler efterföljs, även kunskap om verklig behov och hur lösningar fungerar i praktiken har en betydande roll.

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    Utemiljöer som främjar människors lika värde
  • 273.
    Mohammad, Hossam
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Riquelme, Leonardo
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Analys av prefabricerade installationsbjälklag i koncepthus2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Ventilationssystem tar ofta mycket plats och kan beroende på utformning påverka

    bygghöjden. Studentbostäder kräver låga hyror och därmed låga produktionskostnader.

    Examensarbetet visar hur ventilationssystemet kan byggas in i ett innovativt

    installationsbjälklag och på så sätt spara bygghöjd. Lägre bygghöjd leder till lägre kostnader.

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  • 274.
    Mohammadianfar, Omid
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Imanizabayo, Lambert
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Study of the Bonding Properties for Timber – Glass Composite Beams: The influence of viscoelastic adhesives on the load-bearing capacity2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The study of the influence of viscoelastic adhesives on timber-glass composite beams addresses the development of new and innovative load bearing structures. Hybrid timber-glass beams, comprising of timber flanges and a glass web, were considered. The solutions proposed in this study are based on utilizing viscoelastic adhesive bond lines to obtain optimal structural interaction between timber and glass. For hybrid timber-glass beams, numerical simulations have been developed with Abaqus, Finite element software which are verified by analytical methods according to the Eurocode 5 (EN 1995). In this study, three different bond-line geometries and three adhesives (epoxy, silicone and acrylate) have been investigated. The beams were analyzed under four-point bending. This report summarizes theoretical investigations, background studies, numerical modelling and analytical solution that have been performed. Guidance is presented which can be used for the design of timber-glass composite beams. The study has shown that the viscoelastic properties of the adhesive had no significant influence for the selected epoxy adhesive, but it can slightly affect the beam behavior with the silicone and acrylate adhesives used. From the three geometries studied, the design with an epoxy bond-line on both sides and on top of glass is regarded the best way, leading to good load-bearing structural elements where the response of the adhesive was highly influenced by its near incompressible behavior.

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  • 275.
    Mohammed, Rana
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Ismail, Ahmed
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Hur köksutformning påverkar människors hälsa2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Köket utgör en essentiell del i hemmet. De trånga köken med låga arbetsbänkar följde kvinnorna långt in på 1950-talet, och skapade opraktiska och otrevliga arbetsmiljöer. Studier av olika arbetsmoment i kök gjordes av Carin Boalt och Brita Åkerman, för att på så sätt studera vad som behövdes och därmed skapa en bekväm arbetsmiljö utan tröttande och skadliga moment i arbetet. Dagens kök planeras baserat på olika krav och bestämmelser i avsikt att skapa bra funktioner och underlätta köksarbetet. Men frågan är om dessa, idag inte lika bindande, standarder och byggregler skapar ett rationellt och hälsosamt kök.Syftet med examensarbetet är att få djupare inblick i hur köksutformning utvecklades samt hur utformningen påverkar människors hälsa. För att nå detta studerades bl.a. resultat från Hemmens forskningsinstitut som undersökte köksarbete och dess rörelsemönster. Vidare intervjuades olika kökstillverkare, köksbrukare och en fysioterapeut. Resultatet visar att dagens köksstandard i huvudsak passar majoriteten av köksbrukarna som intervjuades, men statistik från Statistiska centralbyrån, SCB, visar att svenskars samtida medellängd inte passar standardhöjden i kök.

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  • 276.
    Mohlén, Marcus
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Malmberg, Jesper
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Hahrs, Filip
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Dimensioning of slabs for high-speed railway lines2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Swedish Transport Administration has been giving the task to set up a new standard for concrete slabs for the new high-speed railway in Sweden. They are demanding that the concrete slabs must be dimensioned according to the German Beton Kalender 2000. This report will explore the results when dimensioning a slab track, according to the German Beton Kalender 2000. Moment capacity, deformation, and crack width are calculated according to two structural theories, namely slab and beam theory, and a comparison between the two methods is presented.

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    Dimensioning of slabs for high-speed railway lines
  • 277.
    Movehede, Aidin Ramin
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Botic, Martin
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Fuktskador i skolor från 1970-talet i Växjö Kommun2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    På grund av bristande erfarenheter inom byggtekniken gällande fukt har många skolor byggda under 1970-talet fuktproblem idag. I uppdrag av Vöfab ska tre olika fuktskadade objekt som har renoverats jämföras med varandra. Objekten består av tre skolor i Växjö som är byggda under 1970-talet. Objektens fuktskador och åtgärder ska undersökas. Detta görs för att analysera om samma typ av åtgärder vidtagits samt om samma typ av fuktproblem uppkommit i alla tre objekten. I studien ska det med hjälp av det teoretiska ramverket även undersökas om ytterligare fuktproblem kan uppkomma i framtiden trots renoveringarna.

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    Examensarbete Byggteknik
  • 278.
    Muraleedharan, Aishwarya
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Markus Reiterer, Stefan
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Combined glued laminated timber using hardwood and softwood lamellas2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis, the behaviour of glued laminated timber combined with hardwood and softwood lamallae is investigated. The influence of hardwood in the tension and compression zone, in terms of strength and stiffness is evaluated.The basis of evaluation consists of determining the behaviour of beams with various combinations of hardwood solely in the tension zone along with beams with hardwood in the tension and compression zone. The influence of different amount of hardwood for both cases is studied my means of experimental and analytical methods.Experimental data attained by performing bending tests are evaluated for different combinations made from spruce and oak. By comparing the experimental and analytical data an increase in the strength and stiffness in various combinations is observed and potrayed which varies based on different wood species.

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  • 279.
    Murin, Justin
    et al.
    Slovak Univ Technol Bratislava, Slovakia.
    Aminbaghai, Mehdi
    Vienna Univ Technol, Austria.
    Hrabovsky, Juraj
    Slovak Univ Technol Bratislava, Slovakia.
    Balduzzi, Giuseppe
    Vienna Univ Technol, Austria.
    Dorn, Michael
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Mang, Herbert A.
    Vienna Univ Technol, Austria;Tongji Univ, Peoples Republic of China.
    Torsional warping eigenmodes of FGM beams with longitudinally varying material properties2018In: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 175, p. 912-925Article in journal (Refereed)
    Abstract [en]

    In this paper, the influence of torsional warping of thin-walled cross-sections of twisted Functionally Graded Material (FGM) beams with a longitudinal polynomial variation of the material properties on their eigenvibrations is investigated, considering the secondary deformations due to the angle of twist. The transfer relations needed for the transfer matrix method are derived. Based on them, the local finite element equations of the twisted FGM beam are established. The warping part of the first derivative of the twist angle, caused by the bimoment, is considered as an additional degree of freedom at the beam nodes. The focus of the numerical investigation, with and without consideration of the Deformation due to the Secondary Torsional Moment (STMDE), is on modal analysis of straight cantilever FGM beams with doubly symmetric open and closed cross sections. The influence of the longitudinal variation of the material properties and the secondary torsion moment on the eigenfrequencies is investigated. The obtained results are compared with the ones calculated by a very fine mesh of standard solid and warping beam finite elements.

  • 280.
    Music, Nermina
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Lund, Hilda
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Energianalys av Sveriges största skola byggd med passivhusteknik2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In order to achieve Sweden's energy goals, the service sector needs to build energy-efficient buildings. Therefore, the national board of housing, building and planning proposed building regulations called BBR that consists of requirements and general recommendations for both new and existing building and contains multidimensional aspects including energy management in the building. Passive house building is also another promising solution to approach an energy efficient building. The main aim of this study is to assess the energy performance of a case study building according to the both BBR and passive house building criteria. Correspondingly, Elmeskolan, which has been built based on passive house standards, is chosen as the case study and a model is developed using a building energy-modelling program, VIP-Energy.

    The result of the energy calculation has been compared with the requirements of BBR 22 and 25 and the Passive House Standards. The study shows that the requirements for BBR and Passive House Standards were met for the case studied building.

    The primary energy demand of the heat supply system in the building is assessed by considering either geothermal or district heating system according to the Boverket’s energy management building regulations. It is concluded that the primary energy demand in case of using geothermal system is lower than district heating system to supply building heating demand.

    A simplified LCC analysis has been considered in this study due to the passive house standard and BBR 22 and 25 building regulations. The results show energy cost of the case studied building that is built based on passive house criteria is 25 % of total energy cost of similar building that built based on BBR 22 requirements. The results show the benefits of passive house requirements in comparison with BBR regulations for the case studied building in terms of thermo-economic objectives.

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  • 281.
    Muszyński, Lech
    et al.
    Oregon State University, USA.
    Akter, Shaheda T.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Nairn, John
    Oregon State University, USA.
    Bader, Thomas K.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    On the need for reliable rolling shear characteristics in CLT lamellas and for efficient related test methods2019In: Bool of abstract: CompWood 2019, International Conference on Computational Methods in Wood Mechanics – from Material Properties to Timber Structures. June 17-19, 2019, Växjö, Sweden., Lnu Press , 2019Conference paper (Refereed)
    Abstract [en]

    Effective modeling of structural behavior of cross-laminated timber (CLT) elements requires reliable input on the mechanical properties of its laminations. The cross-lamination of layers provides for dimensional stability of CLT elements. In this arrangement, however, all laminations in shear walls and the layers of floor elements oriented perpendicular to the major strength axis transfer shear stress in the radial–tangential plane, often referred to as rolling shear. It is among the least documented characteristics of wood, since it had been of marginal interest for structural lumber and engineered wood composites until the emergence of CLT. While the numerical models may easily account for the contribution of rolling shear in the immediate and long-term deformations of laminated panels, simulations are charged with wide margins of uncertainty because of shortage of reliable experimental data. Rolling shear is not the easiest property to measure, and it received only limited coverage in the literature [1-7]. What has been documented was that the rolling shear strength and stiffness in the cross-layers in CLT floor panels is related to the species, density, growth ring orientation, and manufacturing parameters, but there is no evidence for a meaningful correlation with the grade of lumber, whether established by visual or machine grading. In the presentation, we will discuss the pressing need for reliable data on rolling shear characteristics in clear wood and in structural lumber, their statistical distributions in species important for CLT industry, as well as for efficient test methods to allow generation of relevant data in timely manner. Prototype methods and preliminary data will be presented.

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  • 282.
    Myhrberg, Jakob
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Raab-Obermayr, Gustav
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Koldioxidreducering av en bergtäkts fordonsflotta2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Ballast as a building material is important for developing our society as it’s used as a component in asphalt and concrete. Hence it is important that crushed rock extracted from a quarry have a functioning production to meet the demand that exists, but also because Sweden should be able to reach the goal of being climate neutral 2045. The purpose of this study is to reduce the environmental impact in a quarry from the internal transports and the aim is to bring out suggestions to achieve this. The methods that have been used are literature studies, calculations, simulations and interviews. Through the calculations, a result in this work showed that a reduction of 88 % of carbon dioxide emissions can be made by using the biofuel HVO Diesel 100. In addition, with the help of interviews and literature studies, conclusions have been drawn that the future quarries are believed to produce crushed rock with electric autonomous machines.

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  • 283.
    Ncube, Noah
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Sabaa, Stephen
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Non-uniformly distributed compression perpendicular to the grain in steel-CLT connections: Experimental and Numerical Analysis of bearing capacity and displacement behaviour2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Previous studies have mainly focused on the behaviour of timber under uniformly distributed compression perpendicular to the grain (CPG) loads. However, there are many practical applications in which timber is loaded by non-uniformly distributed CPG loads. Different design and test codes like the Eurocode 5 (EC5), DIN 1052:2004, ASTM D143- 94 and EN-408:2010 only account for load configurations where timber is subjected to uniformly distributed loads. For specific uniformly distributed load (UDL) configurations the bearing capacity of timber (solid softwood timber or Glulam) in compression is adapted by using a load configuration factor (kc,90) according to EC5, the European code for design of timber structures. EC5 has no guidelines for cross-laminated timber (CLT) under UDL with the exception of the Austrian National Regulations for EC5.

    In this work, an experimental and numerical study on the bearing capacity and displacement behaviour of CLT subjected to non-uniformly distributed loading (NuDL) is conducted on eight different load configurations. A steel-CLT connection in which the CLT is partially loaded is used in this study. Finite element modelling, performed using the commercial software Abaqus CAE is used as the numerical simulation of the experimental study and is validated by experimental results. Load configuration factors (kc,90) from experimental results are compared with values from the Swedish CLT handbook (KL-Trähandbok). The outcome of the study shows that load configuration factor for NuDL cases is higher than for UDL cases. Hence, for same load configurations a lower CPG strength is required in NuDL than in UDL. Moreover, numerical results feature overall good congruence with the elastic phase of the experiments and have the potential to augment experiments in further understanding other complex steel-CLT connections

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  • 284.
    Nicklisch, Felix
    et al.
    Technische Universität Dresden, Germany.
    Dorn, Michael
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Weller, Bernhard
    Technische Universität Dresden, Germany.
    Serrano, Erik
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Joint study on material properties of adhesives to be used in load-bearing timber-glass composite elements2014In: Glass | Facade | Energy / [ed] Jens Schneider, Bernhard Weller, Technische Uni Dresden , 2014, p. 271-280Conference paper (Refereed)
    Abstract [en]

    Beyond its transparency, glass offers a large potential to fulfill load-bearing functions. Timber-glass composite elements take advantage of the high stiffness and strength of glass. At the same time the post-breakage behavior of the composite element increases significantly compared to the brittle failure of a pure glass. The current study relates to timber-glass composites where the composite action is obtained via a linear bondline connecting the glass pane to a timber frame. The full potential of these composite elements arises from the use of adhesives of medium and high stiffness which exhibit rather small deformations compared to e.g. structural silicones. A central objective of the research is the assessment and the optimization of the bondline properties with respect to stiffness of the adhesive. The paper summarizes the results of an in-depth study on commercially available adhesives and evaluates their general suitability in timber-glass composites.

    The material properties of the adhesives were determined by thorough mechanical testing of the bulk material in the first place under varying conditions, typically encountered in façades. The potential use in glass-timber composites was then evaluated using small bonded specimens comprising birch plywood or massive pine wood in combination with soda-lime glass. Failure modes were categorized in order to ascertain the influence of the timber strength on the load-bearing capacity.

    In order to guarantee reliable results from various sources, parts of the tests were executed repeatedly at different laboratories. Results were compared and validated throughout the project. Hence the results of this study provide a reliable basis for material models used in e.g. numerical analysis and engineered design solutions. The study presented here is part of the WoodWisdomNet project “LBTGC - Load Bearing Timber Glass Composites”

  • 285.
    Nicoară, Alexandru
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Carlsén, Arvid
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Optimal fönsterstorlek för kontors- och behandlingsrum – Länssjukhuset Kalmar2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete beskriver optimeringsprocessen för ett fönster utifrån relevanta parametrar som tillämpas i Miljöbyggnad 3.0 med avseende på energi och inomhusmiljö. Miljöbyggnad 3.0 är ett miljöcertifieringsystem som bygger på Boverkets Byggregler och Arbetsmiljöverkets regler om arbetsmiljö. De parametrar som fönsterstorleken optimerats utifrån är solvärmelasten, värmeeffektbehovet, den specifika energianvändningen, dagsljuset samt det termiska inneklimatet sommar- och vinter. För betyget i Miljöbyggnad 3.0 på dessa parametrar har fönstrets storlek i förhållande till rummets storlek en avgörande betydelse. Objekten för studien bestod av två typrum, ett behandlingsrum och ett kontorsrum, som kommer att ligga i en framtida byggnad vid Kalmars Länssjukhus. Med hjälp av utredningar och jämförelser mellan teoretiska utgångspunkter och praktiska simuleringar på relevanta parametrar som tillämpas i Miljöbyggnad 3.0 har endast två fönstermått valts för att uppnå minst betygen SILVER i Miljöbyggnad 3.0. Påverkan av invändiga solskydd har även studerats i arbetet.

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  • 286.
    Nilsson, Elin
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Rebecca, Calderon
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Förväntningar och förbättringar på planlösning i flerbostadshus2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The survey has processed expectations and improvements on floor plans in a multi-family house. A survey by the public and residents in Vikaholm, Växjö, and interviews with experts were made to get views of improvements. Also interviews with residents were also made to get more developing and motivational answers than just from the opinion poll.

    The design and layout of the planning has been designed according to the desires and views expressed in the survey. The plan solutions are highly space-efficient and are designed with regard to, inter alia, intangible values that exist in a dwelling, which is spatial qualities that are less obvious and difficult to quantify.

    Different items such as comfort, better furnishing and more storage have made the accommodation a different design than the original floor plans. Flexible and general spaces that meet design requirements and have no unnecessary surfaces have been the aim of the work.

    The results of the work can be used for other future floor plans than for the multi-family house that has been the basis for this degree project.

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  • 287.
    Nilsson, Henrik
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Andersson, Sixten
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Slitage i studentbostäder2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Deta examensarbete undersöker slitaget i Växjöbostäders studentlägenheter genom att genomföra en enkätundersökning och att göra ekonomiska bedömningar av material för ytskikt.

    De ekonomiska bedömningarna görs med hjälp av livscykelanalys (LCC) och de material som analyserades var golv, väggbeklädnad och bänkskiva.

    Examensarbetet undersöker också andra faktorer som kan påverka slitage. 

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  • 288.
    Nilsson, Jonaz
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Ormarsson, Sigurdur
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Johansson, Jimmy
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Moisture-related distortion and damage of lightweight wood panels: experimental and numerical study2017In: Journal of the Indian Academy of Wood Science, ISSN 0972-172X, Vol. 14, no 2, p. 99-109Article in journal (Refereed)
    Abstract [en]

    This study was conducted to increase the knowledge of moisture-related distortion and damage in the field of wood-based lightweight panels. By increasing the possibilities of predicting moisture-related distortion and damage, the possibilities of using lightweight wood materials could increase. The study was performed through experiments and modelling work on a wooden panel product with numerous struts and two thin outer-face sheets of beech-wood glued tightly onto the struts, as well as reference panels of solid wood. During the testing period the results showed the density of the studied lightweight panels to vary from 170 to 290 kg/m3. These panels shrunk and swelled less than the solid wood panels and reacted faster to changes of surrounding humidity and temperature. Moisture related distortions such as twist and bow were not inferior compared to the solid wood panels. Shrinkage or swelling produced moisture related stresses. This may mean that the panel will have a risk of serious damage in the form of cracks or glue release between the outer face sheet and the struts when it is exposed to intense drying. The experimental tests also followed how various damages arose in the panels. Until the damage occurred, the deformation results showed a strong agreement between the experimental and the model findings. Better knowledge of how this type of panel reacts to climate variations is important for the further design and development of this type of product.

  • 289.
    Nilsson, Josephine
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Construction, social structure and policy response in Jamaica - A hurricane hit country: 2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Jamaican hurricane history goes back a long time. The country has an average ratio of getting hit or brushed every 3.84 years and it is estimated to be hit directly every 9.47 years.

    This underscores the relevance of this paper since it seeks to investigate the construction, social structure and policy response of Jamaica.

    The impressions of the author combined with the interviews and literature study resulted in the conclusion of the constructions and social structure not being the main issue, but the policy response.

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    Degree Project - Construction in Jamaica
  • 290.
    Nilsson Malmqvist, Rebecca
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Lagerblad, Lovisa
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Finns det behov av fuktspärr i badrum med korslimmad trästomme?2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna fuktstudie handlar om användandet av diffusionsspärr i väggkonstruktioner i anslutning till badrumsmiljöer med KL-trä som stomme. Metoden som används är datorprogrammet WUFI, som beräknar värme- och fukttransport genom Fourier’s lag, Fick’s lag och Darcy’s andra lag. Indata till programmet är skapad genom mätningar av verkliga badrumsklimats variationer. Resultat från simulering visar att KL-trästommen riskerar mögelangrepp om inget ytterligare ytskikt finns applicerad på insidan av KL-trästommen. En ytskiktssimulering genomförs som visar att ett ytskiktsmaterial med en viss diffusionstäthet måste appliceras på KL-träytan för att undvika fuktrisknivåer inuti konstruktionen.

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    BI_7_LovisaLagerblad_RebeccaNilssonMalmqvist
  • 291.
    Nilsson, Matilda
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Stövegård, Linn
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Flytande studentbostäder, baserat på Compact Living2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Arbetet behandlar en möjlig lösning på bostadsbristen, för dagens Studenter i form av flytande studentbostäder på vatten i ett modulkoncept. Vilket betyder att bostäderna kan förflyttas där bostadsbristen befinner sig.

    Utifrån metoden, System Development, har ett utformningsförslag av en flytande studentbostad lagts fram, baserat på Compact Living.

    Undersökningen baseras på litteraturstudier, observationer och intervjuer. Resultatet visar ett koncept, på hur flytande studentbostäder skulle kunna sättas samman i en modulenhet. 

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    fulltext
  • 292.
    Nordmark, August
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kågesjö, Tobias
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kan industriellt byggande skapa en god arkitektur?: En detaljstudie i utveckling av gaveln på ett modulhus2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Med dagens bostadsbrist är det viktigt för samhället att påskynda byggandet. Därav har byggandet av prefabricerade hus ökat, exempelvis modulhus. Vid denna typ av byggande ligger ekonomi i stort fokus, det kan medföra att arkitekturen blir lidande. Modulhus byggs genom industriellt byggande, på grund av detta är förändringar av konstruktioner ett omfattande arbete då produktionsflödet är känsligt.

    I denna rapport undersöks en önskad förändring av BoKloks husmodell Flex. Förändringen undersöks utifrån arkitektur och produktion. Studien utreder hur förändringen påverkar byggnadens egenskaper ur en arkitektoniskt synvinkel, detta genom en enkätundersökning. Genom ett skissarbete i flera skeden som mynnat i ritningar togs en konstruktion fram för att anpassas till industriellt byggande och därmed BoKloks tillverkning.

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    Kan industriellt byggande skapa en god arkitektur?
  • 293.
    Nylander, Oskar
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Svensson, Sebastian
    Draghållfasthet i historiska träförband2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis was carried out to study tensile strength in pine dowels and cut nails in historical wooden joints. Today no standard of calculations for joints with pine dowels or cut nails exists. By performing tensile tests in combination with calculations according to both Swedish and international standard, the suitability of different formulas will be graded.

     

    The results show that the formulae have a tendency to underestimate the dowels probable tensile strength, although some of them could be applied according to what this study has shown. Further the behavior and strength between different diameter sizes and wooden parts vary unreliably since a greater dowel size didn’t always lead to a higher tensile strength. The same type of failure appeared in all of the joints.

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    Draghållfasthet i historiska träförband
  • 294.
    Nyström, Martin
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Tomaz, Tainan Pantano
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Fatigue analysis of welded joints in a forestry machine: Utilizing the notch stress concept 2015Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Welding is one of the most applied technics in the world for joining steel. Welds are liable to the phenomenon of fatigue, which is, primarily, the formation of a crack and consequently reduction of strength due to the action of time varying loads. Fatigue is one of the main causes of failure in steel structures. The aim of this thesis is to do static and dynamic analyses of a forestry crane with the purpose of using the analyses to determine the lifetime due to fatigue of welded components.

    Two methods for fatigue assessment are used in this work, the Hot-Spot Method and the Notch Stress Method. The first boom, which is a key component for the crane, is analyzed in a Finite Element Method (FEM) software. The found principal stress in accordance with the notch stress method in the first boom is ±165 MPa for the analyzed load case, rendering in a stress range of 330 MPa. The fatigue strength class FAT-225 (m=3), leads to an expected number of 633000 cycles, with a probability of survival of 97,7% for this case.

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    fulltext
  • 295.
    Olsson, Anders
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Determination of sawn timber properties using laser scanning: Development potentials and industrial applications2016In: WCTE 2016 - World Conference on Timber Engineering: August 22-25, 2016, Vienna, Austria. e-book, Full Papers / [ed] Josef Eberhardsteiner, Wolfgang Winter, Alireza Fadai, Martina Pöll, Vienna: tuverlag , 2016, p. 82-91Conference paper (Refereed)
    Abstract [en]

    This paper starts with an overview of methods for machine strength grading of timber being used in industry. It discusses attempts that have been made over the years to improve the accuracy of different grading concepts. Then a newly approved method based on laser scanning and utilization of the tracheid effect is presented. It utilizes high resolution data supplied by an industrial scanner and it gives, in comparison to other methods, very accurate results. Still it is based on several crude assumptions. Therefore the latter part of the paper takes a starting point in the limitations of this scanning based method and discusses what can be done within research and development to reach an even higher grading accuracy. Future work should lead to detailed and accurate models for timber, including geometry of knots, growth layers and fibre orientation in 3D and information of local material stiffness properties, and it should be possible to establish such models for individual boards in productions speed. Some recent and ongoing research that contributes in this direction is discussed. With access to accurate timber models several different strategies for prediction of strength and other engineering properties would be possible.

  • 296.
    Olsson, Anders
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Briggert, Andreas
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Oscarsson, Jan
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Increased yield of finger jointed structural timber by accounting for grain orientation utilizing the tracheid effect2019In: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 77, no 6, p. 1063-1077Article in journal (Refereed)
    Abstract [en]

    Finger joints in structural timber and glulam lamellae are often used to enable production of long members or to allow forre-connection of parts of a member after removal of weak sections. According to the European Standard EN 15497, certainmargins are required between knots and a finger joint in structural timber, which means that a considerable amount of clearwood becomes waste when finger joints are applied. The purpose of this paper was to investigate the possibility of reducingthe quantity of waste using different criteria for placement of finger joints. The investigation was based on (1) applicationof methods of colour scanning and tracheid effect scanning to detect knots and grain disturbance on board surfaces, and (2)interpretation of the requirements of EN 15497 regarding where finger joints may be placed. The standard’s requirementwhen producing finger joints is that the minimum distance between a knot and a finger joint is three times the knot diameter.The standard allows for the minimum distance between a knot and a finger joint to be shortened to 1.5 times the diameterwhen the local fibre orientation is measured. Utilizing this in simulated production resulted in reduction of waste from 7.4to 4.0%, when using finger joints simply to produce timber of long lengths. If finger joints are also used to re-connect partsof members after removal of weak sections, even larger savings can be made. Furthermore, it is concluded that knowledgeof fibre orientation obtained from scanning could be used not only to decrease the waste in production but also to increasethe quality of finger joints.

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    fulltext
  • 297.
    Olsson, Anders
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Källsner, Bo
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Shear modulus of structural timber evaluated by means of dynamic excitation and FE analysis2015In: Materials and Structures, ISSN 1359-5997, E-ISSN 1871-6873, Vol. 48, no 4, p. 977-985Article in journal (Refereed)
    Abstract [en]

    In this study the results from dynamic excitation of 105 centre boards of Norway spruce in edgewise bending are evaluated with respect to shear modulus using the FE method. Advantages of the method presented here, in relation to the torsion method given in EN 408 (Timber structures—structural timber and glued laminated timber—determination of some physical and mechanical properties, 2010), are that the testing is very simple to carry out and also that the shear stresses occur in the same way as in a beam subjected to bending. Although no alternative methods for evaluation of the shear modulus were applied in this study, results indicating a robustness of the suggested method are presented. According to calculations the estimated shear modulus varies considerably between different boards. The calculated mean value and standard deviation of the dynamic shear modulus is about 744 and 106 MPa, respectively. No significant correlation between the estimated shear modulus and the measured static modulus of elasticity in bending was found, but a correlation between calculated shear modulus and density was identified (R2 = 0.24). Conclusions of the results are that dynamic excitation of boards should be considered as an alternative method for determination of shear modulus in EN 408 (Timber structures—structural timber and glued laminated timber—determination of some physical and mechanical properties, 2010), and a relation between the board density and the board shear modulus, rather than a relation between the board MOE and the board shear modulus, should be stated in EN 338 (Structural timber—strength classes, 2009).

  • 298.
    Olsson, Anders
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Källsner, Bo
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Oscarsson, Jan
    Linnaeus University, Faculty of Technology, Department of Building Technology. SP Sveriges Tekniska Forskningsinstitut.
    Enquist, Bertil
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Nytt paradigm för hållfasthetssortering av konstruktionsvirke: Projektrapport två2014Report (Other academic)
    Abstract [sv]

    Undersökningen som redovisas i denna rapport har genomförts under hösten 2013 och våren 2014 inom projektet "Nytt paradigm för hållfasthetssortering av konstruktionsvirke". Projektet, som pågår under perioden december 2011 till juni 2014, går ut på att för industriellt bruk utveckla en nyligen föreslagen metod för hållfasthetssortering av konstruktionsvirke, vilken baseras på laserskanning i kombination med dynamisk excitering och densitetsbestämning av virke. Projektet finansieras till 50 % av VINNOVA och till 50 % av de företag som medverkar i projektet, nämligen Innovativ Vision AB (IV), Vida Vislanda AB, Södra Timber AB, Derome Timber AB och Dynalyse AB. Linnéuniversitetet (Lnu) och SP Sveriges Tekniska Forskningsinstitut AB (SP) samverkar med nämnda företag i utförandet av forskningen.

    Ett syfte med undersökningen är att på ett stort material bestående av många olika virkesdimensioner verifiera de starka statistiska samband som sedan tidigare påvisats för ett begränsat antal plankor och dimensioner, mellan å ena sidan indikerande egenskaper som baseras på mätningar och beräkningar och å andra sidan böjstyrka, elasticitetsmodul och densitet. Ett annat syfte med undersökningen är att visa att nödvändig data kan samlas in av samma utrustning och under samma förhållanden som kommer att gälla vid framtida hållfasthetssortering baserad på den aktuella metoden. Slutligen är ett syfte att samla in och dokumentera data som kan användas för forskning och utveckling både inom och efter det att det aktuella projektet har avslutats.

  • 299.
    Olsson, Anders
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Oscarsson, Jan
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Strength grading based on high resolution laser scanning: performance of a procedure newly approved for the European market2015In: Proceedings of the 19th International Nondestructive Testing and Evaluation of Wood Symposium / [ed] Ross, Robert J.; Goncalves, Raquel; Wang, Xiping, Madison, USA: USDA, United States Department of Agriculture, Forest Service, Forest Products Laboratory , 2015, Vol. 19, p. 232-240Conference paper (Refereed)
    Abstract [en]

    Strength grading of timber is necessary to ensure sufficient structural performance of the material, and machines based on different types of non-destructive measurements are available on the market. The purpose of this paper is to present results on an investigation of a new method and procedure for machine strength grading that is based on laser scanning and utilization of the tracheid effect, in combination with dynamic excitation and weighing. The investigated sample comprised more than 900 pieces of timber of Norway spruce (Picea abies) from Sweden, Norway and Finland. The coefficient of determination between the indicating property (IP) to bending strength and the measured bending strength was as high as R2 = 0.69, while the coefficient of determination between dynamic MOE and measured bending strength was R2 = 0.53. A comparison of the performance with what have been presented for machines that are based on X-ray in combination with dynamic excitation indicates that the new method/procedure will surpass such machines. 

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    fulltext
  • 300.
    Olsson, Anders
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Oscarsson, Jan
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Strength grading on the basis of high resolution laser scanning and dynamic excitation: a full scale investigation of performance2017In: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 75, no 1, p. 17-31Article in journal (Refereed)
    Abstract [en]

    Effective utilization of structural timber requires grading and indicating properties (IPs) that are able to predict strength with high accuracy, and machines that are able to measure the underlying board properties at a speed that corresponds to the production speed of sawmills. The aim of this research is to assess the performance of a new machine strength grading method/procedure which was recently approved for the European market and to compare the performance of it with the performance of other available techniques. The novel method is based on laser scanning utilizing the tracheid effect, in combination with data from dynamic excitation and weighing. Applied indicating properties are defined in detail and results presented include assessment of the repeatability, coefficients of determination between IPs and grade determining properties, and examples of the yield achieved in different strength classes and combinations of strength classes. The investigated sample comprised more than 900 pieces of timber of Norway spruce (Picea abies) from Sweden, Norway and Finland. For this sample the coefficient of determination between the IP to bending strength and the measured bending strength was as high as R2 = 0.69, while the coefficient of determination between dynamic modulus of elasticity (MOE) and measured bending strength was R2 = 0.53. The yield in high strength classes, C35 and above, become about twice as high using the new method/procedure compared to machines using dynamic MOE as IP. A comparison of the performance with what have been presented for machines that are based on X-ray in combination with dynamic excitation indicates that the new method/procedure will surpass such machines as well. 

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    fulltext
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