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  • 1.
    Abdeljaber, Osama
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Avci, Onur
    Do, Ngoan Tien
    Gul, Mustafa
    Celik, Ozan
    Catbas, Necati
    Quantification of Structural Damage with Self-Organizing Maps2016In: Structural Health Monitoring, Damage Detection & Mechatronics, 2016, Vol. 7Conference paper (Other academic)
    Abstract [en]

    One of the main tasks in structural health monitoring process is to create reliable algorithms that are capable of translating the measured response into meaningful information reflecting the actual condition of the monitored structure. The authors have recently introduced a novel unsupervised vibration-based damage detection algorithm that utilizes self-organizing maps to quantify structural damage and assess the overall condition of structures. Previously, this algorithm had been tested using the experimental data of Phase II Experimental Benchmark Problem of Structural Health Monitoring, introduced by the IASC (International Association for Structural Control) and ASCE (American Society of Civil Engineers). In this paper, the ability of this algorithm to quantify structural damage is tested analytically using an experimentally validated finite element model of a laboratory structure constructed at Qatar University.

  • 2.
    Abdeljaber, Osama
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Avci, Onur
    Inman, Daniel
    Genetic algorithm use for internally resonating lattice optimization: case of a beam-like metastructure2016In: Dynamics of Civil Structures, 2016, Vol. 2Conference paper (Other academic)
    Abstract [en]

    Metamaterial inspired structures, or metastructures, are structural members that incorporate periodic or non-periodic inserts. Recently, a new class of metastructures has been introduced which feature chiral lattice inserts. It was found that this type of inserts has frequency bandgaps which can be tuned by altering the geometry of the chiral lattice. Previous studies have shown that inserting non-periodic chiral lattices inside a beam-like structure results in efficient vibration attenuation at low frequencies. In the study presented in this paper, a genetic algorithm based optimization technique is developed to automatically generate chiral lattices which are tuned to suppress vibration in a flexible beam-like structure. Several parameters are incorporated in the optimization process such as the radius of circular nodes and characteristic angle as well as the spacing and distribution of circular inserts. The efficiency of the …

  • 3.
    Abdeljaber, Osama
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Younis, Adel
    Qatar University.
    Avci, Onur
    Qatar University.
    Gul, Mustafa
    Ozan, Celik
    Zhang, H
    Dynamic Testing of a Laboratory Stadium Structure2016Conference paper (Other academic)
    Abstract [en]

    Studies with large physical models are a vital link between the theoretical work and field applications provided that these models are designed to represent real structures where various types and levels of uncertainties can be incorporated. While comprehensive analytical and laboratory joint studies are ongoing at Qatar University, University of Central Florida and University of Alberta, this paper presents the initial findings of dynamic testing at Qatar University. A laboratory stadium structure (grandstand simulator) has been constructed at Qatar University. Capable of housing thirty spectators, Qatar University grandstand simulator is arguably the largest laboratory stadium in the world. The structure is designed in a way that several different structural configurations can be tested in laboratory conditions to enable researchers to test newly developed damage detection algorithms. The study presented in this paper covers the finite element modeling and modal testing of the test structure.

  • 4.
    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. 

  • 5.
    Adam, Thellsson
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Dagvattenkvalitet i Växjö kommun2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 6.
    Addassi, Mouadh
    et al.
    Technical University of Denmark, Denmark.
    Johannesson, Björn
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Wadsö, Lars
    Lund University.
    Inverse analyses of effective diffusion parameters relevant for a two-phase moisture model of cementitious materials2018In: Cement and Concrete Research, ISSN 0008-8846, E-ISSN 1873-3948, Vol. 106, p. 117-129Article in journal (Refereed)
    Abstract [en]

    Here we present an inverse analyses approach to determining the two-phase moisture transport properties re-levant to concrete durability modeling. The purposed moisture transport model was based on a continuumapproach with two truly separate equations for the liquid and gas phase being connected by the sorption ki-netics. The moisture properties of ten binder-systems containingfly ash, calcined clay, burnt shale and graymicro-filler, were investigated experimentally. The experiments used were, (i) sorption test (moisturefixation),(ii) cup test in two different relative humidity intervals, (iii) drying test, and, (iv) capillary suction test. Masschange over time, as obtained from the drying test, the two different cup test intervals and the capillary suctiontest, was used to obtain the effective diffusion parameters using the proposed inverse analyses approach. Themoisture properties obtained with the proposed inverse analyses method provide a good description of the testperiod for the ten different binder-systems.

  • 7.
    Addassi, Mouadh
    et al.
    Technical University of Denmark, Denmark.
    Schreyer, Lynn
    Washington State University, USA.
    Johannesson, Björn
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Lin, Hai
    University of Colorado Denver, USA.
    Pore-scale modeling of vapor transport in partially saturated capillary tube with variable area using chemical potential2016In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 52, no 9, p. 7023-7035Article in journal (Refereed)
    Abstract [en]

    Here we illustrate the usefulness of using the chemical potential as the primary unknown by modeling isothermal vapor transport through a partially saturated cylindrically symmetric capillary tube of variable cross-sectional area using a single equation. There are no fitting parameters and the numerical solutions to the equation are compared with experimental results with excellent agreement. We demonstrate that isothermal vapor transport can be accurately modeled without modeling the details of the contact angle, microscale temperature fluctuations, or pressure fluctuations using a modification of the Fick-Jacobs equation. We thus conclude that for a single, axisymmetric pore, the enhancement factor depends upon relative humidity boundary conditions at the liquid bridge interfaces, distance between liquid bridges, and bridge lengths.

  • 8.
    Ahlgren, Sara
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Lindström, Jenny
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Ekonomi, kunskap och kommunikation: – Avgörande för den estetiska kvaliteten vid nyproduktion av bostäder2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There are indications that the architecture in Sweden is perceived as more and more monotonous with the absence of aesthetic qualities. Architects are allowed to bear responsibility for the claim but they themselves believe that they deprived their position in the construction process where they are replaced under ongoing projects, ancillary financial interests.

    The goal of the work was to find out what happens to a building's aesthetic qualities when the architect is replaced and what lies behind the replacement of the architect. A comparison of two objects was made, one in which the architect has been involved throughout the process and one where the architect has been replaced. The study was conducted through fact-finding from literature, observations and interviews.

    The result shows that the desire to build beautifully with aesthetic qualities is strongly linked to the client's level of ambition. However, the overall result shows that aesthetic values are subordinated to the economy of the construction-process. Furthermore, it has emerged during the work with this essay that there is a lack of knowledge and difficulties in communication between the actors in the construction industry, especially between architects and contractors. 

  • 9.
    Ahmad, Elaf
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Hultgren, Mathilda
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Möjligheter för visualisering i presentation av småhus2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Rapporten behandlar hur husleverantörer kan utveckla presentationsmaterial. De materialen som visas är olika husmodeller från företagen och behandlar bakgrundsvyer samt förbättringar i digital media. Företaget som ligger till grund för rapporten är Trivselhus, och undersökningarna i rapporten är baserade på aktörer i anknytning till företaget. Resultatet kan även tillämpas hos andra husleverantörer.

    Visualisering handlar om hur människan tar till sig den informationen som ges. Den används för att underlätta förståelsen för komplicerade bilder och idéer som visas för kunder. Visualisering möjliggör att bearbetade bilder kan kopplas samman med slutresultatet som presenteras.

    Informationen som kommer genom visualisering kan fås genom människans fem sinnen syn, lukt, hörsel, smak och känsel. Denna studie lägger fokus på den synliga aspekten till visualisering och hur företag kan använda den för att förstärka sin kundkrets.

    Resultatet ger exempel på visualisering som husleverantörer kan tillämpa i verksamheten. Det behandlar bland annat utveckling av hemsidor och gemensamma plattformar som kund och säljare båda kan arbeta i. Andra framtidsförslag som presenteras är en utveckling av visningshus samt producering av miniatyrhus. Detta för att ge kunden en bättre visualisering och därmed en större insyn i hur det färdiga huset är utformat och kommer fungera i verkligheten.

  • 10.
    Akter, Shaheda
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bader, Thomas K.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Enquist, Bertil
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Failure envelope for interaction of stresses perpendicular to the grain with rolling shear stress in wood2018In: 6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11 – 15 June 2018, Glasgow, UK, 2018Conference paper (Refereed)
    Abstract [en]

    The orthotropic material property in combination with ductility in compression, brittleness in shear and tension, very low shear modulus in radial-tangential (RT) plane etc. requires anisotropic stress failure criteria, as well as their evolution with increasing strains. Three- dimensional failure criteria have been proposed for this purpose, but their validation in the RT plane with interaction of rolling shear stresses has attracted less attention. Corresponding stress interactions are however important for modelling of engineered wood-based products under compression perpendicular to the grain when taking into account influence of the annual ring structure.

    The work aims at defining failure envelopes for stresses perpendicular to the grain with rolling shear stress interaction based on experimental investigations performed on Norway spruce. The experimental set-up was realized in a biaxial testing frame and consisted of stiff steel plates to transfer load from the testing machine to wood specimen. Mechanical grips prevented rotation and uplifting of the specimen in case of pure shear and tensile loading, respectively. In addition to conventional linear variable differential transformers, a digital image correlation system was used to measure strain fields on the surface of wood specimens and steel plates. Measurements of dog-bone shaped specimens were carried out along different stress interaction paths by displacement controlled loading.

    The experimental dataset was then compared with commonly used phenomenological failure criteria, namely Tsai-Hill, Tsai-Wu [1], Norris [2] and Hoffman, as well as with regression equations from previous works [3].Experiments revealed that the stress-strain relationship under compression, shear, and biaxial loading differs in radial and tangential directions. None of the three-dimensional stress failure criteria provided good prediction of experiments under compression and rolling shear, but experimental data was closer to the regression equation proposed in [3].

  • 11.
    Akter, Shaheda Tahmina
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bader, Thomas K.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Serrano, Erik
    Lund University, Sweden.
    Modeling of wood under combination of normal stresses with rolling shear stress2019In: Presented at CompWood 2019 - International Conference on Computational Methods in Wood Mechanics - from material properties to Timber Structures, Växjö, Sweden, June 17-19, 2019, Växjö, Sweden, 2019Conference paper (Refereed)
  • 12.
    Akter, Shaheda Tahmina
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bader, Thomas K.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Serrano, Erik
    Lund University, Sweden.
    Modelling of wood under compression perpendicular to the grain with rolling shear in cross-laminated timber2019In: Presented at COMPLAS 2019 - XV International Conference on Computational Plasticity: Fundamentals and Applications, Barcelona, Spain, September 3-5, 2019, Barcelona, Spain: European Community on Computional Methods in Applied Sciences (ECCOMAS), 2019Conference paper (Refereed)
  • 13.
    Al Haddad, Aiham Emil
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Wind-induced Vibration Control of Tall Timber Buildings: Improving the dynamic response of a 22-storey timber building 2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Plans for construction of the tallest residential timber building has driven the Technical Research Institute of Sweden (SP), Linnaeus University, Växjö and more than ten interested companies to determine an appropriate design for the structure. This thesis presents a part of ongoing research regarding wind-induced vibration control to meet serviceability limit state (SLS) requirements. A parametric study was conducted on a 22-storey timber building with a CLT shear wall system utilizing mass, stiffness and damping as the main parameters in the dynamic domain. Results were assessed according to the Swedish Annex EKS 10 and Eurocode against ISO 10137 and ISO 6897 requirements. Increasing mass, stiffness and/or damping has a favorable impact. Combination scenarios present potential solutions for suppressing wind-induced vibrations as a result of higher efficiency in low-increased levels of mass and damping.

  • 14.
    Albertsen, Henrik
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Lindberg, Amanda
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Lokalt omhändertagande av dagvatten på bostadsfastigheter2016Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [sv]

    Ett behov finns av att fördröja dagvatten innan det släpps på det kommunala ledningsnätet för att minska flödestopparna och undvika överbelastning. Studien avser att ta fram en förenklad metod för val och utformning av LOD-metod som är anpassad för privata fastighetsägare.

    Ett flertal LOD-anläggningar samt förutsättningar kring dessa har undersökts. Studien har gett en grundläggande information och en beräkningsgång som har förenklats, är lätt att följa och som kan anpassas efter befintliga förutsättningar och önskemål. 

  • 15.
    Al-Chaderchi, Balsam
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Abuabed, Mohammed
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kartläggning av vattenskador- inverkan av byggsystem och aktörernas attityd2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The study aims to investigate water damage that has become increasingly common in Swedish buildings. Water damage exposes humans to health risks due to a high risk for microbial growth. The purpose of the work is to discuss water damage, where water damage occurs and why, what costs do the insurance companies cover and what costs do the property owners cover. The study also examines how different actors view water damage and risks with different types of frame material. The result of the study is that the insurance companies assess all frame materials equally in terms of compensation for water damage, that is, they treat wood and concrete frames in the same way. However, the age of the building is more decisive as they make age deductions to evaluate the compensation for the respective water damage. Damage should be remedied as soon as possible, the faster the damage is rectified the less water damage spreads. The method used in the work was a qualitative method and the reliability is considered high since the results are consistent with the theoretical starting points.

  • 16.
    Aldarwash, Mustafa
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bajqinca, Alban
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Nybyggnation av badrum : Jämförelse mellan prefabricerat och platsbyggt ur ett ekonomiskt perspektiv2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med arbetet är att, genom en ekonomisk undersökning skapa underlag som visar vilket alternativ av produktionsmetoderna prefabricerat eller platsbyggt badrum som är att föredra vid en nybyggnation av vårdhem. 

    Resultatet visar att det platsbyggda badrummet ger en ökad totalt kostnad på 627457 kr vilket motsvarar 11,1 procent dyrare än det prefabricerade badrummet. 

  • 17.
    Al-Darwash, Mustafa
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Nuss, Emanuel
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Mechanical characterization of DuraPulp by means of micromechanical modelling2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Södra DuraPulp is a relatively new eco-composite, made from natural wood fibers and polylactic acid (PLA), which comes from corn starch. Until now, there are only few applications for DuraPulp, mainly in the area of design. To find new fields of application, more knowledge about its mechanical material properties are of great interest.This study deals with characterizing the mechanical properties of DuraPulp in an analytical way by means of micromechanical modelling and evaluation with help of Matlab. The mechanical properties for PLA were taken from scientific literature. Not all properties of the wood fibers could be found in literature (particularly Poisson’s ratios were unavailable). Therefore, they partly had to be assumed within reasonable boundaries. These assumptions are later validated regarding their influence on the final product.Figures and tables were used to present and compare the in- and out-of-plane E-Moduli, shear moduli and Poisson’s ratios of DuraPulp. The calculated in-plane E-Moduli were then compared to those obtained from an earlier study, where DuraPulp was tested in tension. The results showed that experimental and analytical values are very similar to each other.

  • 18.
    Aldén, Jonathan
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Pålsson, Kristian
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Robertson, Johan
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Krav och kvalitetssäkring av BIM-objekt inom projektering, produktion samt förvaltning2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den ökade användningen av BIM har ändrat villkoren inom byggsektorn. Arbetet syftar till att identifiera och definiera de krav och kvalitetssäkringar av BIM-objekt som finns inom projektering, produktion samt förvaltning. Avsaknad av en gemensam standard försvårar kravställning och kvalitetssäkring av BIM-objekt vilket har lett till vissa komplikationer, främst vid konvertering mellan olika programvaror.

    BIM är med sin potential med största sannolikhet en stor del av byggsektorns framtid. För att kunna ta nästa steg i utvecklingen måste en gemensam standard gällande krav och kvalitetssäkring utarbetas.

  • 19.
    Ali Nima, Salwan
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Mammo, Adey-Abeba
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Hasnein Tareq, Shahad
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Utveckling och utformning av nya återvinningscentralen i Häringetorp i Växjö kommun2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete är utfört för att ge Växjö kommun ett underlag för utformning av en ny ÅVC på Häringetorp. Återvinningscentralen ska vara estetisk tilltalande för att öka trivsel för både brukare och personal. Vid utformning måste hänsyn till trafiksäkerheten tas för att undvika problem. Utformningen påverkar även sorteringskvalitén hos det sorterade avfallet, Resultatet uppnås genom att forska, granska och utreda. Utöver detta ska dessutom utformningen av återvinningscentralen påverka sorteringskvalitén på så vis att det ska vara enkelt konstruerat samt att det ska finnas en välbetänkt yta med utrymme för att sortera avfallet. 

  • 20.
    Ali Qahtan, Nawar
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Donna, Sojeva
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    En alternativ mötesplats i modern arbetsmiljö2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studien behandlar utformning av en tillbyggnad som länkas samman med en befintlig byggnad och en planerad byggnad. Det på uppdrag av Videum AB som planerar att bygga ett nytt kontorshotell på Videum Science Park och vill ha en interstruktur som innehåller restaurang, reception och konferensrum. Denna tillbyggnad ska bli mötesplatsen för Videums personal, hyresgäster och för allmänheten.

    Resultatet visar ritningar, illustrationer och förklaringar över interstrukturen.

  • 21.
    Alijagic, Denis
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Att uppnå god energiprestanda: En jämförelse av teoretiska energiberäkningar och verklig energianvänding i småhus2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    En studie som utfördes på uppdrag av Norrköpings kommun med syfte att undersöka varför energideklarationer visar en annan specifik energianvändning gentemot energiberäkningar. Ett stickprov togs där tio småhus energiberäkningar och energideklarationer analyserades. Dessutom genomfördes intervjuer med tre medelstora kommuner (Norrköpings-, Linköpings- och Jönköpings kommun) samt Boverket för att lokalisera möjliga fel och förbättringar gällande Boverkets Bygg Regler, BBR. Boverkets föreskrifter och allmänna råd om fastställande av byggnadens energianvändning vid normalt brukande och ett normalår, BEN, togs även i beaktande att lokalisera felkällor i upprättade energiberäkningar för hus 1-10.

  • 22.
    Almaari, Firas
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Aljbban, Essam
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Strain Rate Effect on Fracture Mechanical Properties of Ferritic-Pearlitic Ductile Iron.2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study investigates the effect of strain rate on fracture properties of Ferritic-Pearlitic Ductile Iron.

    A series of dynamic three point bending tests, with various load application rates, are conducted on Charpy V-notch specimens, in room temperature and approximately -18 °C.

    The tests are performed in a custom-made fixture and during the tests, force and displacement data are recorded. A XFEM (Extended Finite Element Method) model of the test setup has been established and material data from the tests are used as input to the model.

    The test results show a strong dependency of the strain rate regarding the force needed for crack initiation. Moreover, it can be concluded that low temperature makes the material very brittle, even at low load application rates.

  • 23.
    Alriksson, Tobias
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Visualisering av byggprojekt i Revit2014Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    Rapporten avhandlar visualiseringen i marknadsföringsstadiet av ett byggnadsprojekt med tillämpning på Trivselhus bostäder. För att få en grund till vad som ska ändras gällande företagets nuvarande visualisering har intervjuer genomförts med samtliga berörda parter. Dessa är säljare, kunder och husdesigners. Efter detta har två förslag till förändringar av nuvarande visualiseringar arbetats fram i Revit med intervjuerna som underlag.

  • 24.
    Andersson, Alexander
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bergman, Carl
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Underlag för fördelaktig upphängning av kylvattenledningar i en äldre byggnad2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Arbetet redovisar möjligheterna att hänga upp tyngre vattenledningar i en äldre industrilokal där en äldre byggnadsstandard användes vid uppförandet.

    Ett flertal alternativ har tagits fram och där de mest lämpade har arbetats vidare genom att jämföra fördelar och nackdelar.

  • 25.
    Andersson, Bernt-Ove
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Malmstedt, Anthon
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Innovativa boendeformer för unga vuxna: En möjlig väg in på den svenska bostadsmarknaden2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This work concerns the examination of the interest and awareness of three innovative forms of housing that target young adults between the ages of 18 and 35 in the Swedish housing market. It also describes the existing stock of housing and highlights the most serious obstacles for the target group to obtain an accommodation. The work takes it’s starting point in the current housing shortage in Sweden where many groups for various reasons are hindered from the housing market for various reasons. The market is in need for public actors and various housing developers to find new ways to remedy the problem of obtaining an accommodation for these vulnerable groups. The study is based on previous research, surveys with young adults and interviews with intermediaries from different parts of the industry as a methodology. The results show an interest for, but low knowledge about the three types of housing: rent purchases, youth sets and cooperative rental apartments adapted for young adults. These are all adapted to reduce the problem for some persons within the target group to enter the housing market.

  • 26.
    Andersson, Carl
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Pettersson, John
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Behovet av ökad kontroll i stålbyggnadskonstruktioner2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the work the need of increased inspections of steel structures with respect to errors of execution was examined. On 1 June 1994, the Swedish parliament decided to change the Planning and Building Act (PBL) and the changes came into force in 1995, where the entire responsibility for the construction and control of a building was placed on the developer. After the winters of 2009/10 and 2010/11, when several roofs collapsed by the snow weight, a number of design and execution faults were discovered. During the thesis work it was investigated what happens to the safety of building structures in steel that undergo changes during its lifetime and a comparison with current regulations was made.

    A field study and several interviews were conducted where the focus was on execution errors and how changes in regulations led to today's self-control systems that affect the number of execution errors. The results of the work show that there may be a need to review the current control system and that the number of serious execution errors in the case study object increased after 1995.

  • 27.
    Andersson, Jenny
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Malin, Enbom
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Hur ökas implementering av visuella arbetssätt inom Skanska?2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Visuella arbetssätt har visat sig vara effektivt inom byggbranschen. Studien omfattar de visuella arbetssätt som Skanska använder sig av; visuell styrning och visuell projektering. Syftet med studien är att öka antalet projekt som väljer att implementera arbetssätten. Därav har underliggande problem identifierats varför inte projekt väljer att implementera arbetssätten i den utsträckning som Skanska önskar.

    Det har visat sig under studiens gång att visuell projektering har implementerats i större utsträckning än visuell styrning, detta för att visuell projektering har ett mer utvecklat underlag. En jämförelse av verktygens implementering har gjorts.

  • 28.
    Andersson, Josefine
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Svensson, Simon
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Mätning av fuktkvot i sammansatta KL-träelement2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Moisture related damage is an occurring problem in wood-based buildings if the material is exposed to rainfall during construction. Measurement of moisture content can be done with various instruments and methods. The purpose of the thesis is to study change in moisture content in cross-laminated-timber, with prolonged exposure to water in laboratory environment. To advance the field, the Linnaeus University has been developing a measurement instrument of their own in collaboration with the company Saab. The instrument measures electrical resistance in wood where the obtained values will be compared to similar measurements from a product named Gigamodule. The self-developed sensor card is still a product under development. In addition to the lab setting measurements the instrument was also installed in a local building in Växjö.

    To verify the result from the previously mentioned resistance measurers additional instruments and methods have been utilized. Two separate models have been used to represent the detail of the connection between the wall element and the joist. Both models have been submerged under water for an equal amount of time. The experimental setting took place between the 19th of April to the 18th of May 2018. The measurements and calculations have been resulting in values that can be the subject of internal evaluation. Difference in result based on the direction of the grain have been observed in several measurement methods. The CLT-elements demonstrated good drying properties despite periodically high moisture content and the wood indicate a return towards initial levels of moisture.

  • 29.
    Andersson, Matilda
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Ekholm, Matilda
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Källström, Sofia
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Utveckling av en grönyta i ett miljonprogramsområde2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete ger ett studerat utformningsförslag på ett outnyttjat grönområde imiljonprogramsområdet Norrliden i Kalmar.Studien har resulterat i ett förslag till förbättrad utformning, en visuell skiss utifrånrelevant teori, intervjuer med sakkunniga och enkätsvar från de som bor i området. Fokushar legat på att öka gemenskap mellan människor i olika åldrar, kön och bakgrund.

  • 30.
    Andersson, Sandra
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bengtsson, Linn
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Utredning och analys av en vattenreservoars utformning och dimensioneringsprocess2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The essay contains an assessment of water reservoirs, where an examination and analysis of storage volumes and construction solutions are carried out. Today there are no clear guidelines for how reservoirs in smaller communities should be designed and dimensioned to ensure water quality and guarantee a safe water supply. The goal and purpose of the essay is to calculate a storage volume, identify important aspects to consider in designing a reservoir, and present advantages with and the need of a water reservoir based on consumption variations. The assessment is limited to Lammhults’s conditions where interviews, observations, literature studies, analyses and calculations serve as a foundation for the theory and the result. The result demonstrates, among other things, difficulties, difficulties in analyzing consumption variations, the importance of local correct statistics and questioning of existing methods of dimensioning a storage volume. The essay partially some problem areas, but further studies are required to find solutions in the sector and straight guidelines regarding dimensions and design of reservoirs. 

  • 31.
    Aronsson, Alexander
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Gustavsson, Markus
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Minimering av köldbryggor vid balkonger hos miljonprogramshus2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I studien görs en klimatsimulering av en byggnad från miljonprogrammet och jämförs sedan med en klimatsimulering där en ombyggnation av byggnadens indragna balkonger har gjorts.

    Studien ger konstruktionslösningar på hur en ombyggnation skulle kunna se ut.

    Resultatet visar att det går att minska energibehovet om balkongväggarna rivs och nya väggar konstrueras i liv med fasaden.

  • 32.
    Aronsson, Anton
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Sjöberg, Mikael
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Förskola i kombination med andra verksamheter: Vilka konsekvenser medför detta?2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Växjö kommun har ont om ledig mark vilket har medfört att en undersökning harpåbörjats, där förskolor kombineras med andra verksamheter i en och sammabyggnad. Syftet har varit att undersöka möjligheten med dessa kombinationer för attse vilka konsekvenser som uppstår.

    Undersökningen behandlar två tomter i Växjö som har olika förutsättningar gällandedess detaljplaner. Resultatet visar att en kombination mellan de olika verksamheternaär möjligt men att dagens regler och standardiseringar inte alltid går att ta hänsyn tillvid dessa kombinationer.

  • 33.
    Assofi, David
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bijelic, Petar
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Ventilationseffektivisering i skolbyggnader: 2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studien går ut på att jämföra tre olika styrsystem för ventilation, nämligen CAV (Constant Air Ventilation), VAV (Variabel Air Ventilation) och DCV (Demand Controlled Ventilation). Dessa styrsystem ställs mot varandra i tre olika lokaltyper, med syfte att identifiera det mest energieffektiva styrsystemet. Ett syftet med studien är också att upptäcka vid vilka flöden det lönar sig att arbeta med VAV- och DCV-styrsystemen.

  • 34.
    Athanasiadis, Michail
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Al Sahi, Hussein
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Val av stomsystem för en offentlig lokal: Fallstudie avseende entreprenadformen partnering och beaktade av miljöperspektiv2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Production and operation of buildings accounts for a large part of global carbondioxide emissions, and it is therefore important to investigate the importance of thechoice of buildings' frame systems in terms of energy consumption and climateimpact over a lifecycle. The purpose of this study is partly to show how differentparts of a frame system in a public premise can be evaluated and chosen on the basisof environmental impact and partly to investigate how the contractual-/collaborativepartnership work in the development of a public premise.

    A case study of a newly established psychiatric clinic was conducted, and the studyincluded review of project documents, interviews with project participants andcalculations. The results showed that the building could, to a large extent, beconstructed with wood rather than with concrete. This would have resulted in bothreduced transmissions of heat and reduced carbon dioxide emissions from theproduction of materials. The reasons for choosing the prefabricated concrete slabs inprefabricated concrete walls, rather than a wood-based solution, were above all thecontractor's greater experience of working with concrete, coupled with the fact thatthe client would not risk a long production time or unexpected costs. More time fordialogue, analysis and greater openness for working with new solutions could haveled to a more environmentally friendly solution.

  • 35.
    Augustino, Daudi Salezi
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Adjei Antwi-Afari, Bernard
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Parameterized Modelling of Global Structural Behaviour of Modular Based Two Storey Timber Structure2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The global stiffness behaviour of modular-based two storey timber structures was studied under prescribed horizontal displacements at the upper corners of the volume modules. To be able to study this behaviour, a numerical finite element model was created in Abaqus. A parametric study was performed in which the geometry and spring stiffness of joints were varied until the enough stiff module was attained for safe transfer of shear forces through the module structure. The FE-model was parameterized to have possibility to vary positions of door and window openings in the volume modules. These openings had influence on the global structural behaviour of the two storey module structure since the side wall with two openings showed less reaction forces at its top corner point A compared to the other wall point B. In addition, the module#3 was assigned with small spring stiffness in x-direction representing friction in the joint between the volume modules. This was done without uplift plates and angle brackets. The findings showed that there was significant slipdeformation between the volume modules and small reaction forces at points A and B. The spring stiffness value in x-direction was varied until large value was obtained which resulted in overall shear deformations of the walls in both volume modules. When the angle bracket and the uplift plates were introduced between the modules when small spring stiffness along the joint between the volume modules was used, the results showed that most of the shear forces were transferred through the angle brackets instead of the fastener joints between the modules. Moreover, the results showed that the reaction forces at the points A and B increased when the angle brackets were assigned in the module. Furthermore, the results also showed that uplift plates used in the model worked well for simulations with low vertical spring stiffness between the modules.

  • 36. Avci, Avci
    et al.
    Abdeljaber, Osama
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kiranyaz, Serkan
    Inman, Daniel
    Vibration suppression in metastructures using zigzag inserts optimized by genetic algorithms2017In: Shock & Vibration, Aircraft/Aerospace, Energy Harvesting, Acoustics & Optics, 2017, Vol. 7Conference paper (Other academic)
    Abstract [en]

    Metastructures are known to provide considerable vibration attenuation for mechanical systems. With the optimization of the internal geometry of metastructures, the suppression performance of the host structure increases. While the zigzag inserts have been shown to be efficient for vibration attenuation, the geometric properties of the inserts affect the suppression performance in a complex manner when attached to the host structure. This paper presents a genetic algorithm based optimization study conducted to come up with the most efficient geometric properties of the zigzag inserts. The inserts studied in this paper are simply cantilever zigzag structures with a mass attached to the unsupported tips. Numerical simulations are run to show the efficiency of the optimization process.

  • 37. Avci, Onur
    et al.
    Abdeljaber, Osama
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kiranyaz, Serkan
    Boashash, Boualem
    Sodano, Henry
    Inman, Daniel
    Efficiency Validation of One Dimensional Convolutional Neural Networks for Structural Damage Detection Using A SHM Benchmark Data2018Conference paper (Other academic)
    Abstract [en]

    In this paper, a novel one dimensional convolution neural network (1D-CNN) based structural damage assessment technique is validated with a benchmark study published by IASC-ASCE Structural Health Monitoring Task Group in 2003. In contrast with predominant machine learning based structural damage detection techniques of the literature, the technique shown in this paper runs without manual feature extraction or preprocessing stages. It runs directly on the raw vibration data. In CNNs, the stages of feature extraction and feature classification are merged into one stage; therefore, the proposed technique is efficient, feasible and economical. Utilizing the optimal features learned by 1D CNNs, the proposed CNN-based technique considerably improves the classification efficiency and accuracy. The performance improvement of the proposed technique is assessed by calculating the “Probability of Damage” values for damage estimations. The unseen structural damage cases between the two extreme end structural cases (zero damage and total damage) were successfully identified. Consequently, it is validated that the improved CNN-based technique is efficient since it predicted the level of damage consistently with the structural damage cases defined in the existing benchmark.

  • 38. Avci, Onur
    et al.
    Abdeljaber, Osama
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kiranyaz, Serkan
    Inman, Daniel
    Control of Plate Vibrations with Artificial Neural Networks and Piezoelectricity2020In: Sensors and Instrumentation, Aircraft/Aerospace, Energy Harvesting & Dynamic Environments Testing, 2020, Vol. 7Conference paper (Other academic)
    Abstract [en]

    This paper presents a method for active vibration control of smart thin cantilever plates. For model formulation needed for controller design and simulations, finite difference technique is used on the cantilever plate response calculations. Piezoelectric patches are used on the plate, for which a neural network based control algorithm is formed and a neurocontroller is produced to calculate the required voltage to be applied on the actuator patch. The neurocontroller is trained and run with a Kalman Filter for controlling the structural response. The neurocontroller performance is assessed by comparing the controlled and uncontrolled structural responses when the plate is subjected to various excitations. It is shown that the acceleration response of the cantilever plate is suppressed considerably validating the efficacy of the neurocontroller and the success of the proposed methodology.

  • 39. Avci, Onur
    et al.
    Abdeljaber, Osama
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kiranyaz, Serkan
    Inman, Daniel
    Convolutional Neural Networks for Real-Time and Wireless Damage Detection2020In: Dynamics of Civil Structures, 2020, Vol. 2Conference paper (Other academic)
    Abstract [en]

    Structural damage detection methods available for structural health monitoring applications are based on data preprocessing, feature extraction, and feature classification. The feature classification task requires considerable computational power which makes the utilization of centralized techniques relatively infeasible for wireless sensor networks. In this paper, the authors present a novel Wireless Sensor Network (WSN) based on One Dimensional Convolutional Neural Networks (1D CNNs) for real-time and wireless structural health monitoring (SHM). In this method, each CNN is assigned to its local sensor data only and a corresponding 1D CNN is trained for each sensor unit without any synchronization or data transmission. This results in a decentralized system for structural damage detection under ambient environment. The performance of this method is tested and validated on a steel grid laboratory structure.

  • 40. Avci, Onur
    et al.
    Abdeljaber, Osama
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kiranyaz, Serkan
    Inman, Daniel
    Structural Damage Detection in Real Time: Implementation of 1D Convolutional Neural Networks for SHM Applications2017In: Structural Health Monitoring & Damage Detection, Springer, 2017, Vol. 7Conference paper (Other academic)
    Abstract [en]

    Most of the classical structural damage detection systems involve two processes, feature extraction and feature classification. Usually, the feature extraction process requires large computational effort which prevent the application of the classical methods in real-time structural health monitoring applications. Furthermore, in many cases, the hand-crafted features extracted by the classical methods fail to accurately characterize the acquired signal, resulting in poor classification performance. In an attempt to overcome these issues, this paper presents a novel, fast and accurate structural damage detection and localization system utilizing one dimensional convolutional neural networks (CNNs) arguably for the first time in SHM applications. The proposed method is capable of extracting optimal damage-sensitive features automatically from the raw acceleration signals, allowing it to be used for real-time damage detection. This paper presents the preliminary experiments conducted to verify the proposed CNN-based approach.

  • 41. Avci, Onur
    et al.
    Abdeljaber, Osama
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kiranyaz, Serkan
    Inman, Daniel
    Structural Health Monitoring with Self-Organizing Maps and Artificial Neural Networks2020In: Topics in Modal Analysis & Testing, 2020, Vol. 8Conference paper (Other academic)
    Abstract [en]

    The use of self-organizing maps and artificial neural networks for structural health monitoring is presented in this paper. The authors recently developed a nonparametric structural damage detection algorithm for extracting damage indices from the ambient vibration response of a structure. The algorithm is based on self-organizing maps with a multilayer feedforward pattern recognition neural network. After the training of the self-organizing maps, the algorithm was tested analytically under various damage scenarios based on stiffness reduction of beam members and boundary condition changes of a grid structure. The results indicated that proposed algorithm can successfully locate and quantify damage on the structure.

  • 42.
    Axelsson, Johanna
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Lacalendola, Stefania
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Kulturarvets själ och karaktär jämlik för alla: en studie om till- och frångänglighet i Kalmar residens2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This analysis has been conducted to show that it is possible to combine accessibility, accessible evacuation and cultural heritage buildings, in this case especially Kalmar residence, without distorting the building. 

    The study was performed as a case study. By studying laws, regulations and rules as well as interviewing experts and comparing solutions with other buildings, the residence will become accessible. The aim of this work is to deliver a solution proposal. This proposal should also be used as an inspiration for future projects of similar complex types. 

    The study has come to the conclusion that there is a need for more laws and rules on accessible evacuation and that accessibility is an aspect that should be taken more into consideration in cultural heritage buildings. It is important that everyone can take part in society on an equal basis. 

  • 43.
    Ay, Philip
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Attar, Ribhi
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Riktlinjer för social hållbarhet: vid gestaltning av socioekonomiskt utsatta områden2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper illustrates how the built environment affects the social sustainability in areas with socio-economic difficulties. The focus is on how municipalities, real estate companies and other actors work on issues concerning design, housing, physical environment, security and safety, health, influence and participation. The purpose of this study is to gather knowledge about the subject and to highlight the meaning of it. The aim is to develop guidelines for the establishment of a social development plan or during the development of a region.

    Research that focuses on the subject as well as interviews with municipalities, real estate companies and an expert has been central to the preparation of the guidelines. Interviews and previous research correlate with each other and illustrate how the physical environment has an impact on the residents and their well-being. The study places important research in connection with an inclusive collaboration process and provides an explanation for involving concerned actors and existing residents in the development of the area's physical environment. A mix of buildings and operations is important. This together with an open and attractive physical environment, can in long terms contribute to increased movement and feelings of safety. Public transport in relation with activities and good connections can make it easier for residents to establish social contacts.

  • 44.
    Bader, Thomas K.
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bocquet, Jean-Francois
    ENSTIB/LERMAB, University of Lorraine, France.
    Schweigler, Michael
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Lemaitre, Romain
    ENSTIB/LERMAB, University of Lorraine, France.
    Numerical modeling of the load distribution in multiple fastener connections2018In: Design of Connections in Timber Structures: A state-of-the-art report by COST Action FP1402/WG3 / [ed] Carmen Sandhaas, Jorgen Munch-Andersen, Philipp Dietsch, Aachen: Shaker Verlag, 2018, p. 221-239Chapter in book (Refereed)
  • 45.
    Bader, Thomas K.
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Bocquet, Jean-Francois
    University of Lorraine, France.
    Schweigler, Michael
    Vienna University of Technology, Austria.
    Lemaitre, Romain
    University of Lorraine, France.
    Numerical modeling of the load distribution in multiple fastener joints2017In: International Conference on Connections in Timber Engineering – From Research to Standards: Proceedings of the Conference of COST Action FP1402 at Graz University of Technology / [ed] Reinhard Brandner, Andreas Ringhofer & Philipp Dietsch, Graz: Verlag der Technischen Universität Graz , 2017, p. 136-152Conference paper (Refereed)
    Abstract [en]

    Numerical modeling approaches, for the determination of load distribution in laterally loaded joints, as well as for the assignment of stiffness properties of joints for the structural analysis, are summarized in this contribution. The effect of the nonlinearity and the load-to-grain orientation dependence of connection slip, of elastic deformation in the surrounding wood matrix, and of the deviation between load and displacement direction are discussed. Comparison of various models demonstrates the pronounced effect of the load-to-grain orientation dependence and the nonlinearity in connection slip on the load distribution, particularly in case of moment loading. The effect of elastic deformation in the wood matrix on the load distribution increases with increased size of joints, even more pronounced when joints are loaded by a shear force perpendicular to the grain. In case of normal force loading, the non-uniform load distribution due to elastic deformation in the wood matrix reduces rapidly with increased relative joint displacement. Pros and cons of the modeling approaches as well as necessary input data are discussed in relation to the design process and European standardization.

  • 46.
    Bader, Thomas K.
    et al.
    Vienna University of Technology, Austria.
    Dorn, Michael
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Esser, Gerold
    Vienna University of Technology, Austria.
    Hochreiner, Georg
    Vienna University of Technology, Austria.
    The Historical Roof Structure of the Leopold Wing of the Vienna Hofburg Palace: Structural Assessment2015In: Proceedings of the International Conference on Structural Health Assessment of Timber Structures (SHATIS'15), 2015Conference paper (Refereed)
    Abstract [en]

    In this case study, the structural behaviour of the historic roof structure of the “Leopold Wing”, part of the Hofburg, the Vienna Imperial Palace, is assessed. The current appearance of the roof is a consequence of several adaptions and extensions of the original structure that dates back to the 17th century. The main part of the roof was reconstructed in the early 1670s following a disastrous fire in February 1668. The structure had the shape of an M-roof consisting of two adjacent gable roofs. Probably in the 19th century, the centre part was closed, creating a mansard roof over the entire width of the building. Basically, the geometry of the structure is symmetric with respect to the middle wall. However, since the position of the middle wall is partly asymmetric, also the roof structure becomes asymmetric. Herein, the influence of the building history on the load-deformation behaviour of the roof structure is investigated. Therefore, structural analyses of the original M-roof and of the mansard roof are performed. The modelling of the historic roof structure is based on a deformation-accurate survey. In addition, the influence of the nonlinear, compliant behaviour of connections on the load-deformation behaviour of the timber structure is taken into account. A considerable influence of the connection slip on the deformation of the structure becomes obvious from the analysis. Consequently, consideration of the nonlinear behaviour of the joints reveals a realistic load transfer within the structure. The addition of structural elements caused additional dead loads, which increase long-term deformations.

  • 47.
    Bader, Thomas K.
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology. TU Wien, Austria.
    Schweigler, M.
    TU Wien, Austria.
    Hochreiner, Georg
    TU Wien, Austria.
    Eberhardsteiner, Josef
    TU Wien, Austria.
    Dorn, Michael
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Serrano, Erik
    Lund University, Sweden.
    Integrative Research for an Enhanced Design of Dowel Connections2015In: Proceedings of the EUROMECH Colloquium 556 on Theoretical, Numerical, and Experimental Analyses in Wood Mechanics, 2015Conference paper (Refereed)
  • 48.
    Bader, Thomas K.
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Schweigler, Michael
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Numerical modelling of the rope effect in laterally loaded dowel-type connections2018In: 6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11 – 15 June 2018, Glasgow, UK, 2018Conference paper (Refereed)
    Abstract [en]

    Theory of laterally loaded dowel-type fasteners is well understood in relation to their bending deformation as a consequence of lateral embedment stresses in wood. Modelling of the so- called rope effect has however attracted less attention. The rope effect in laterally loaded connections is evoked by withdrawal resistance of the shank as well as by axial resistance of the head of the fasteners. It describes the development of tensile forces along the axis of the fastener, as a consequence of its bending deformation and axial constrains. Hilson [1] emphasized the pronounced contribution of frictional forces in the shear planes that contribute to increased strength of laterally loaded connections. The axial force component parallel to the shear plane however will only become significant for large relative displacements. Different kind of numerical models have been proposed for the simulation of dowel-type connections, including 3D FEM with elasto-plastic material models, with damage mechanics, or so-called foundation models. In this contribution, calculations with a beam-on-nonlinear foundation method [2] will be presented. The model was extended to account for increased lateral connection strength due to withdrawal resistance of fasteners. This was implemented in terms of axial springs that encompass a withdrawal force-relative displacement relationship, similar to the lateral springs that hold information on the embedment behaviour. Friction between the connected timber members was taken into account by the frictional coefficient times the force component perpendicular to the shear plane, which is a result of the axial force in the fastener.

    Calculations were performed for different types of dowel-type fasteners, including screws, smooth shank nails, annular-ringed shank nails and smooth dowels. Model predictions were compared to experimental data and showed good agreement. This encourages the use of the beam model for the engineering design of dowel-type connections in timber structures based on a deeper understanding of structure-connection relationships [3].

  • 49.
    Bader, Thomas K.
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Schweigler, Michael
    Technische Universität Wien, Austria.
    Hochreiner, Georg
    Technische Universität Wien, Austria.
    Eberhardsteiner, Josef
    Technische Universität Wien, Austria.
    Ingenieurmodelle für die Strukturmodellierung und Nachweisführung von stiftförmigen Verbindungen im Holzbau: (Engineering models for the structural design and verification of dowel-type connections in timber structures)2017In: Österreichische Ingenieur- und Architekten-Zeitschrift, ISSN 0721-9415, Vol. 162, no 1-12, p. 1-9Article in journal (Refereed)
    Abstract [en]

    Connections of elements in timber structures play an important role, not only due to their pronounced effect on the mechanical behavior of structures, but also due to the fact they can be decisive for the economic success of timber structures. Herein, approaches for a calculation of the ductile load-displacement behavior of dowel-type connections, of multi-dowel joints and of stresses in their timber matrix, by means of numerical methods, are presented. With these methods, kinematically compatible relative deformations of joints under arbitrary plane loading conditions and their effect on the mechanical behavior of timber structures can be reasonably predicted. The combination of the presented models and their integration in the structural analysis and the verification of timber structures lead to a more realistic prediction of their behavior (internal forces, stresses and deformations), as well as to a more economic design of timber structures. 

  • 50.
    Bader, Thomas K.
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology. Vienna University of Technology, Austria.
    Schweigler, Michael
    Vienna University of Technology, Austria.
    Hochreiner, Georg
    Vienna University of Technology, Austria.
    Eberhardsteiner, Josef
    Vienna University of Technology, Austria.
    Serrano, Erik
    Lund University.
    Dorn, Michael
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Enquist, Bertil
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Experimental Assessment of the Load Distribution in Multi-Dowel Timber Connections2016In: 17th International Conference on Experimental Mechanics, Rhodes, Greece, July 3-7, 2016, 2016Conference paper (Other academic)
    Abstract [en]

    An integrative, hierarchically organized testing procedure for the quantification of the load distribution in multi-dowel timber connections is presented herein. The use of contactless deformation measurement systems allowed the combination of test data from single dowel and multi-dowel connections, which gave access to the loads acting on each dowel over the full loading history. As a consequence of the anisotropic material behavior of wood, a nonuniform and progressively changing load distribution among the dowels was found.

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