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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Structural Analysis of Deep Composite Box-Type Components with application to a proprietary stabilising timber wall element

Atashipour, Seyed Rasoul January 2016 (has links)
The stabilising wall element of the Trä8-system is a deep box-type beam/column element which is made of different types of timber composites including framing members of gluedlaminated timber (glulam) and sheathings of laminated veneer lumber (LVL). This element is used as a ―shear wall‖ in multi-storey buildings up to four storeys. To be able to optimise thecomposite stabilising element and use its maximum potential and efficiency, it is necessary to have sufficient fundamental knowledge and information about the structural behaviour and influences of different mechanical properties and geometrical parameters and dimensions of the sub-elements.In this thesis, structural analysis and design principles of the Trä8 stabilising wall element are discussed, including the early stage of erection during assembly to the final usage and residence. A list of required fundamental basic analyses are presented, including accurate deflection analysis for the serviceability limit state, local pre- and post-buckling of the LVL sheathings, global buckling as well as the lateral-torsional buckling of the stabilising element in different design situations. This thesis is then focused on deformations and local instability. For each type of structural problem, accurate, but simple and general methodology is employed to incorporate a large number of effective geometric and property parameters. In this way, a fast evaluation of the influence of different parameters is possible for a wide range of values without needing several time-consuming 3-D finite element (FE) simulations. In several cases, the accuracy and validity of the obtained solutions and formulae are examined and confirmed by comparing their results to those based on the 3-D FE simulations. First, different composite beam theories including shear effects are employed for deflection analysis of the stabilising timber element. Next, an accurate energy-based methodology isdeveloped rendering an explicit formula that gives accurate predictions for the deflection of the stabilising element within a medium range of sheathing or web thicknesses and/or stiffnesses. For weak shear webs, however, this model is not sufficient. Therefore, another new model based on the partial composite interaction theory is developed for accurate deflection predictions of the element having weak shear webs. This model contains simple but accurate formulae for deflection analysis of any similar composite box-type of element with an arbitrary range of geometry and property parameters.Next, shear buckling of the rectangular LVL-panel between the framing members are analysed using differential quadrature (DQ) numerical technique as well as an explicit analytical solution and a formula is established for accurate and fast prediction of the shear pre-buckling of the LVL. This study is extended by considering the effect of each individual lamina of the LVL as well as general orthotropic material properties using a laminated theoryand the DQ solution approach. Further, the post-buckling of the LVL panel is studied based on a simple analytical method with rotating stress fields together with the accurate 3-D FE simulations. A simple formula is then proposed for accurate prediction of the shear post-buckling resistance of the LVL-panel in the stabilising element. As a result of the thesis concerning the two main focus areas, deformations and local instability, explicit analytical formulae are presented for the design of the box-type stabilisingelement with respect to deflections including shear effects in the serviceability limit state and with respect to local shear buckling of the sheathings of the stabilising element including the post-critical area in the ultimate limit state. / <p>Godkänd; 2016; 20160217 (rasata); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Seyed Rasoul Atashipour Ämne: Träbyggnad/Timber Structures Avhandling: Structural Analysis of Deep Composite Box-Type Components With Application to a Proprietary Stabilising Timber Wall Element Opponent: Professor Per Johan Gustafsson, Avd för byggnadsmekanik, Lunds tekniska högskola, Lunds universitet, Lund. Ordförande: Professor Ulf Arne Girhammar, Avd för byggkonstruktion- och produktion, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet, Luleå Tid: Fredag 18 mars, 2016 kl 10.00 Plats: F1031, Luleå tekniska universitet</p>

Dimensionering och praktiska försök av kopplingar i HD/F-plattor / Dimensioning and practical tests of connections in HD/F-slabs

Holmström, Linnea January 2017 (has links)
Håldäck är en vanligt förekommande betongprodukt som ger lägre materialkostnadader och används bland annat där man önskar längre spännvidder för en öppnare planlösning. Strängbetong konstruerar, tillverkar och monterar prefabricerade betongelement där håldäck är en av de produkterna. För att få en stabil och robust konstruktion behöver betongelementen kopplas samman. Detta för att undvika fortskridande ras av en byggnad ifall en olycka skulle inträffa som t.ex. påkörning eller explosion. Examensarbetet syftar till att undersöka två så kallade raskopplingar mellan ett håldäck och en betongvägg. Ena kopplingen är enligt Strängbetongs standard och utformas med en bygel igjuten i håldäckets kanal, denna standardlösning ger dock extra arbete vid tillverkningen. Därför undersöks ifall det är praktiskt möjligt att montera bygeln i fogen mellan två håldäck istället. Försöken är till för att undersöka ifall armeringsbygeln blir tillräckligt omsluten av betong och att fogen därmed inte spricker sönder vid belastning av järnet. Resultaten från den praktiska delen samt från den teoretiska beräkningen sammanställs sedan för att kunna se om praktiken skiljer sig från teorin. Domkraftens dragkapacitet var 20 ton som gjorde att försöken begränsades till att enbart kunna konstatera att utdragningskapaciteten i en håldäcksfog och kanal är minst 195 kN. Resultatet från dragförsöken av armeringsbyglarna igjutna i håldäckets fog och kanal blev materialbrott i armeringen. Resultaten visar att det är möjligt att ersätta dagens standard koppling i kanalen med att istället montera bygeln i fogen mellan två håldäck. Examensarbetet kan ses som ett försök till att testa ifall kopplingen var möjlig och kan vara till grund för vidare studering. / Hollow core slabs are a common concrete product that reduces material costs and is used, among other things, where you want longer ranges for a more open plan solution. Strängbetong designs, manufactures and assembles prefabricated concrete elements where hollow core slabs are one of the products. To get a stable and robust construction, the concrete elements need to be connected. This in order to avoid progressive collapse of a building in case of an accident, such as an collision or explosion. This dissertation aiming to investigate two so-called collapse-couplings between a hollow core slab and a concrete wall. One of the connections is according to Strängbetong's standard and is designed with a S-reinforcing bar in the hollow core slab void, but this standard solution provides extra work in the manufacture. That's why it's an advantage, if it is practically possible, to assemble the bar in the joint between two slabs instead. The tests are in order to investigate whether the bended reinforcement bar becomes enought enclosed by concrete and that the concrete in the joint does not crack apart. The results from the practical part and from the theoretical calculation are then compiled to see if the reality differs from the theory. The capacity of the jack was 20 ton, which made the tests limited to only note that the pull-out capacity of a hollow core slab joint and void is at least 195 kN. The result of the tests gave material ultimate in the reinforcement. The results show that it is possible to replace today's standard connection in the void by instead assembly the bar in the joint between two slabs. The dissertation can be seen as an attempt to test if the connection is a possible solotion and the work may be the basis for further study.

Vad får q-ltur kosta?

Lindström, André January 2017 (has links)
No description available.

Internationell studie om stålfiberarmering

Ljajic, Tarik, Darouiche, Khaled January 2019 (has links)
No description available.

Optimal ljudnivå i bostäder : En undersökning om det är möjligt att maskera spolljud från wc med ventilationsljud / Optimal sound level for housing

Ludéen, Emma, Nordin, David January 2019 (has links)
A lot of people experience sound pollution in their home even though the demands for sound levels are met. The majority of new constructions does not only fulfill the basic requirements but also reach the higher classifications that are presented by the Swedish Standards Institute. Even though this is the case, people still make complaints about being disturbed by noise. Bjerking AB states that they require an inquiry if it is possible to mask the noise from a disturbing sound with a background sound. The study also investigates if it is possible to mask the noise even more with a filtered background sound. The thought behind the masking of the sound is to add a background sound that is able to cover the disturbing sound and therefore make it harder to perceive. A test environment has been created based on the question about the possibility of masking a flushing sound from a toilet with a background sound. Twelve test persons have participated in the test using a signal when they identified the disturbing sound during different test scenarios. The result showed that it was in most scenarios possible to mask the disturbing sound with background sound and even better with a filtered background sound. Continuous research is needed to create a more secure method that studies the possibility of masking flushing noise from a toilet. Other types of noise should also be studied to gain a broader picture if masking can be applied to mask noise in residencies.

Energieffektiviseringsmöjligheter i kulturhistoriska byggnader

Tawfeeq, Safeen, Håkansson, Gustav January 2019 (has links)
All around the country there are historic buildings considered to have a cultural heritage value and are therefore historically important and should be preserved.  They are an important part of a city’s identity and it is important to preserve them so that they can keep being part of our societies. The thesis of this study is therefore to explore the possibilities for how these buildings can become more energy efficient, so that they can meet today’s standards and keep being functional. Cultural heritage buildings can be subject to legal preservation and for every building there are individual preservation requirements that are to be considered. Three fictional buildings with different preservation requirements have thus been created to take into consideration all the challenges and possibilities that can present themselves.   The result shows the multitude of opportunities, but that these can vary greatly between buildings and cases. It is always the individual building’s preservation requirements and its premise that are the determining factors for if the solutions are applicable or if the value is affected negatively. Thus, a thorough prestudy is always significant before every project. Window retrofit solutions are mostly made of adding additional glass and sealing, which in many cases can be applied to existing windows without further complications. Ventilation and heating systems, however, require more space and are in most cases a more difficult retrofit action. Though, in some cases existing canals and pipelines can be utilized for installation of the new system, without affecting the heritage value negatively. Energy efficient retrofits in cultural heritage buildings could bring value and should therefore be considered. By retrofitting the building’s existing systems with newer and modernized techniques the indoor climate can be greatly improved, and thus the building’s use can be broadened, and it can continue to be a functional part of the city.


Herbertsson, Alexander, Gunnarsson, Oscar January 2019 (has links)
No description available.


Eriksson, Lars January 2019 (has links)
SWECO structures har genomfört en utredning gällande kraven på konstruktionsdokumentation och hur huvudkonstruktörens samordnande roll ska definieras. I och med otydliga formuleringar i boverkets konstruktionsregler och interna samordningsproblem på SWECO uppstod behovet att definiera hur företaget ska tolka dessa krav och hur samordningen av konstruktionsarbetet kan förbättras. Resultatet av utredningen blev en mall för konstruktionsdokumentation, ett flödesschema för hur arbetet med dokumentet ska fungera samt en rollbeskrivning av huvudkonstruktörens uppdrag. Denna rapport redogör för en utvärdering av dessa resultat och hur varje enskild del kan förbättras. Till grund för utvärderingen ligger det juridiska underlaget i boverkets konstruktionsregler, EKS samt synpunkter som framkommit under samtal med personer från de berörda yrkesgrupperna; En byggherre, en förvaltare, en byggnadsinspektör samt en huvudkonstruktör från SWECO structures i Umeå. I rapporten redovisas även ett exempel på hur delar av den framtagna mallen för konstruktionsdokumentation kan användas. / SWECO structures has conducted an investigation in order to clarify the interpretation of new judicial requirements when constructing buildings and to resolve some of the company’s co-ordination problems. The judicial requirements consist of the demand to present a new form of document, a structural design documentation, meant to give a short form description of the conditions for the design, execution of the construction and the behavior of the load bearing structure. The requirements have been hard to interpret and SWECO structures wanted to determine which information is to be presented and how to design the document in a uniform way. Relating to the company’s co-ordination problems SWECO has identified the need for a coordinating head engineer whose specific tasks and responsibilities were meant to be specified. The results of this investigation were a form for the structural design documentation, a flowchart describing the work process and a list of the head engineers’ tasks and responsibilities. This report consists of an evaluation of these results where suggestions on how each individual part, the form, the flowchart and the head engineers’ tasks and responsibilities, can be improved is presented. The results have been evaluated based on how well they meet the judicial requirements and the opinions of people from the relevant fields; one property developer, one property manager, one building inspector and one head engineer from SWECO structures in Umeå. The report also contains an example of how the form for the required document can be used in future projects.

Bodens Kommun i 3D

Nilsson, Albin January 2019 (has links)
sida 1Sammanfattning:Det här projektet har gåttut på att skapa en slags 3D-miljö över Bodens kommun som man kan använda sig av för olika sakerinom kommunen. Projektetskapades i ArcGis-Pro, skillnaden mellan vanliga ArcGis och Pro är att man kan skapa 3D-miljöer i Pro.Det somjag gjorde var att jag användemig av data från lantmäteriet och kommunen för att först generera varje byggnad i kommunen som kuber. Det som jag gjorde efter var attanvändemig av laserdatanfrån lantmäteriet för att forma byggnaderna och taken på byggnader samt fixa rätt höjd på byggnadernaså att 3D-miljön skulle stämma så bra som möjligt med själva verkligheten.Det är viktigt att höjderna och tak formernastämmer så bra som det går eftersom tanken är att man ska använda 3D-miljön för olika analyser eller att visa hur utsikten kan vara från en nybyggd lägenhet m.m.Vi har hållit oss till en viss kvalitetsnivå i det här projektet som gör att man kan visa höjderna på husen och hur taket ser ut i stort sett. Vi har undvikit att göra detaljer som t.ex. räcken, skorstenar m.m. eftersom det finns ungefär 35000 byggnader i Boden och det hade tagit en så otroligt lång tid att skapa alla byggnader i Boden i detalj. Men för att visa staden på ett rättvist sätt i 3D så räcker det att hålla sig på den nivå som vi har lagt oss på nu i starten.Själva idénför att göra det här projektet hadefunnits i kommunen väldigt länge. Många större kommuner med mer resurser har tidigare skapat 3D-miljöer över vissa områden men det har inte riktigt funnits tid eller kunskap om det här i Boden. När ArcGis-Pro släpptes och när Geosecma började arbeta med att få över sina tillägg till Pro så började man få lite idéer. Jag hade tidigare frågat om det fanns möjlighet att göra ex-jobb och/eller sommarjobba på kommunen efter min praktik var färdig och då satte sig hela Gis-avdelningen ner och pratade om hur man skulle göra. Dem kom fram till att starta det här 3D-projektet som jag kunde arbeta med som ex-jobb och även jobba vidare på under sommaren. Tanken är nu att i framtiden så ska all Gis-information finnas i 3D så att man kan göra fler analyser ochvisa staden i alla olika vinklar.Vi har fått väldigt bra respons från andra delar av kommunen, andra kommuner och olika företag som har sett vad vi håller på med och vad man kan göra med 3D-miljön. Ett exempel är att vi har hjälpt en av planarkitekterna att visa hur ett nytt bostadsområde kan passa in där det just nu inte finns något alls.I sin helhet så har det här varit ett riktigt givande och lärorikt projekt att arbeta på. Eftersom ArcGis-Pro är fortfarande ganska nytt så lär man sig nya saker nästanhela tiden medans man jobbar för att utveckla kommunen som man har bott i hela sitt liv.Efter ex-jobbet är klart så kommer jag fortsätta att jobba vidare på den här 3D-miljön och utveckla den så mycket det går. / This project has consisted ofcreating a 3D-enviroment of Boden that can be used for a lot of different things municipality. The project was created in ArcGis-Pro, the difference between ArcGis and ArcGis-pro is that Pro can be used to create 3D-enviroments. The thing i did was that iused data from Lantmäteriet and the municipality to generate every building in the municipality as individual cubes. Then i used the heightdata to shape the cubes and the roofs of all the different houses. I did this to create a 3D-enviroment that matchedthe town as good as possible.It was very important that the heights and shapes of the roof were correct because we want to use this enviroment to do different kinds of analyzes and tests on the city. Like showing the view from a newly built apartment.Wehave kept the project on a certain ”quality-level” so we can show the different heights and all the shapes of the roofs. We have avoided small details like chimneys, railings and other samll details. Because there is 35000 buildings in the whole municipality we dont want to waste to much time on this. But to show the town in a good and fair way we have atleast kept us on this level.The idea to make this project has been in the municipality for quite a while now. Alot of bigger towns with more resources and people have made certain 3D-models in the past but here in Boden it has not really been time or knowledge to do it. When ArcGis-Pro launched and Geosecma slowly started to work with their add-ons for Pro the people working here started to get some ideas.I asked in the middle of my internship if there was a possibility for me to do my ex-job and/or summerjob in the same place. After that the whole Gis-department sat down and talked about different projects that could be worked with and they came up with this idea. The thought is that we will use all of our Gis-information in a 3D-model in the future to make more and better analyses and show the city in more than one angle.We got alot of great response frpm other authorities, other municipalitys and different companies that have seen what we are doing and what the 3D-enviroment can be used for. A great example is that we have helped one of our architects to show how a new neighborhoos can look and fit in a space where right now there is just nothing at all.All in all so have this been a very educational and fun project. Because ArcGis-Pro is relatively new i still learn new thins almost everyday i work with this program to help develope the town i have spent my whole life in.After the ex-job has ended so will i keep working with this 3D-enviroment to upgrade it as much as possible.

KL-trä eller lättbalkar : Egenskaper vid påbyggnad av två våningar / KL-wood or light beams : Characteristics of storey extension by two levels

Gustafsson, Stefan January 2019 (has links)
No description available.

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