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Optimering av flervåningsbyggnadsstruktur genom att ersätta bärande väggar med pelare och balkarAhmed, Ali Mohamed, Rashid, Obaidullah January 2023 (has links)
I takt med att den globala befolkningen fortsätter att växa, ökar efterfrågan på nya bostadsbyggnader avsevärt. Samtidigt har behovet av bostäder och byggande vuxit över hela världenunder de senaste decennierna, vilket har lett till en ökad efterfrågan på byggmaterial. Betong ärdet viktigaste byggmaterialet för flervåningsbyggnader pga. sin hållfasthet, men det bidrarbetydligt till utsläppen av växthusgaser. För att minska koldioxidavtrycket och främja hållbarhet är det avgörande att minimera materialanvändning med moderna byggmetoder.Syftet med denna studie är att optimera flervåningsbyggnadsstrukturer genom att ersättabärande väggar med pelare och balkar. Studien använder en referensbyggnad belägen iSandvikens kommun och verktyget StruSoft FEM-Design. Studien genomförs i två steg.I steg 1 utförs modellering, design och analys av referensbyggnaden med bärande väggar(byggnad 1). I steg 2 genomförs en förändring av byggnadsstrukturen genom att ersätta debärande väggarna med pelare och balkar av armerad betong (byggnad 2). Samma procedurersom i steg 1 upprepas för den omkonstruerade strukturen. Resultaten jämförs medreferensbyggnaden med hänsyn till utnyttjandegrad, deformation, spänningar, reaktioner, viktoch stabilitet.Ersättningen av bärande väggar med bärande pelare och balkar av armerad betong har variteffektiv. Båda strukturerna uppfyller de nödvändiga kraven. Baserat på resultaten ärdeformationen 9 mm för byggnad 1 och 7 mm för byggnad 2, vilket indikerar att skillnaden ideformation mellan de två strukturerna inte är signifikant.Byggnad 1 har en maximal utnyttjandegrad på 87%, medan byggnad 2 har en högre maximalutnyttjandegrad på 99%. Detta innebär att byggnad 2 kan utnyttjas i större utsträckning änbyggnad 1. Reaktionskrafterna är 563,6 respektive 476,4 kN i båda byggnaderna, vilketindikerar att reaktionskrafterna i byggnad 2 är 15% lägre än i byggnad 1. Båda strukturerna ärstabila, men det finns en skillnad i byggnadernas totala vikt. Vikterna på byggnaderna är 4169respektive 3 143 ton. Resultatet indikerar att byggnadens totala vikt minskar med ca 25% vidanvändning av betongpelare och betongbalkar.
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Jämförelse av bjälklagstyper - Samverkansbjälklag (KL+betong) & KL-träbjälklag / Comparison between flooring types - CLT-concrete composite floor & CLT floorEriksson, Jens, Åberg, Ludvig January 2023 (has links)
No description available.
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Separations- och filtreringsstabilitet hos cementbaserat injekteringsbrukDraganovic, Almir January 2007 (has links)
Bleeding of cement based grout Bleeding of cement based grout is a complex problem. How it occurs and which basic mechanism causes and influences bleeding have been questions for discussion. Therefore the aim of the thesis is to illustrate what really happens with grout during bleeding and which factors influence it. In this way relevant measuring methods can be developed as well as the knowledge regarding how to interpret measuring results to joints in rock. The bleeding tests show that there are two basic mechanisms which cause bleeding. They are sedimentation and consolidation. It also means that the bleeding process is influenced by sample height. It was found that bleeding of coarse cement (ANL) was mainly a result of sedimentation of the grout. Experiment with fine cement (INJ30; d95<30 µm) shows that the consolidation part of bleeding was larger. The study shows that the bleeding process for a low sample height (10 mm) occurs fast. Extrapolation of experiment results and theoretical analysis shows that bleeding in a joint happens very fast and takes place during grouting itself. It means that results measured by standard methods can not be applied straight off for joints in rock. Theoretically bleeding occurs relatively slowly in vertical or inclined joints due to increased height. Bleeding will be resisted by arching and hardening. Reasonably, very little bleeding will take place. Filtration of cement based grout How far grout penetrates into a joint is not just influenced by the rheology of the grout like viscosity and shear strength, but also by the tendency of the grout to get stuck which means to build a plug. Factors which influence the building of a plug are properties of the grout, geometry of the joints including rawness of the joints and proceeding of the grouting. Today there are many different ways to measure filtration of a grout or the building of a plug. The different methods give different results and thus the importance of the influence of different factors is interpreted differently. The experiments in this thesis are done in a 100 mm long, 50 mm wide aperture with 1 mm width. Thereafter the width of the aperture decreases to 0.02 – 0.3 mm over a 10 mm long distance. The results of the experiments in this thesis, measured by own method, show that the best penetration ability with respect to filtration has a grout based on relatively fine-graded cement (INJ30; d95<30 µm).The penetrability of the grout based on more graded cement decreases because of flocculation. In total tens measurements have been done. The measurements confirm others’ experiments which show that the concentration of fine-graded particles (< 4 µm) has a large influence on flocculation and with that the building of larger grains. It is important to remind that the mixing of grout has been done by a laboratory mixer, which is not a mixer of colloidal type. This issue has to be further tested. The research shows that filtration of grout is also influenced by grain size of cement and the water cement ratio. The filtration test carried out by own measuring method with varying pressure showed a better penetrability for a larger pressure. It influenced both arching and erosion of the accumulated particles. / QC 20101104
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Stabilitly analysis of large structures founded on rock : an introductory studyJohansson, Fredrik January 2005 (has links)
Previous investigations of Swedish and international dams have shown difficultiesto assess the safety against failure in rock foundations. The problem was alsogiven additional interest in connection to the recent construction of the newbridge at Traneberg in Stockholm. This project was created in order to increasethe knowledge in the subject of stability analysis of large structures founded onrock, and how they should be performed in order to describe the safety in areliable way. This thesis covers the first half of this project. The objectives of the thesis were todescribe the knowledge and current state of practice in the subject with a literaturestudy, and with a case study of the arch dam at Krokströmmen show the problemsfor stability analyses where foundation and structure interact. The objective wasalso to produce a foundation for future work. At Krokströmmen arch dam, previous three dimensional finite element analyseshave been performed (Johansson and Palmgren 1996). In these analyses, thestiffness of the foundation was not considered. Based on the results from theseanalyses, stability was analytically analyzed for each monolith by Stille et al.(2002). The results indicated low factors of safety for the central monoliths. As aconsequence, a reinforcement slab was constructed to increase stability. In order to show how varying stiffness and non-linear resistance of the foundationaffects stability, a quasi three dimensional finite element analyses were carriedout. In these analyses, five of the central monoliths were first analyzed separately.Thereafter, the reaction forces were adjusted to fit the results from the analyses byJohansson and Palmgren (1996). The monoliths were thereafter coupled togetherwith assumptions of equal deformations and constant total reaction forces for thefive monoliths. Through an iterative procedure, constant deformation and newredistributed reaction forces were obtained. These forces were used to discuss thestability for one of the monoliths in detail. This thesis shows that the problem is more complex than described in the Swedishdam safety guidelines, RIDAS (Svensk Energi 2002), and the Swedish bridgedesign code, BRO 2004 (Vägverket 2004). An accurate analysis of the stability ina rock foundation under large structures demands a more refined approach, whichconsiders the specific features associated with rock mechanical problems. Thecase study showed that the interaction between foundation and structure can beconsiderable; deformations and reaction forces acting on the foundation wereredistributed when the stiffness of the foundation was considered. Furthermore,the resistance is a function of deformation. These aspects are necessaryconsidering if stability should be determined with high confidence. An additional question which was identified and brought up for discussion wasthe possibility of time-dependent deformation in the foundation at Krokströmmendue to creep and cyclic loading, which in turn can affect the long term stability. / QC 20101203
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Structural design for serviceabilityReid, Stuart G. (Stuart Grant) January 1981 (has links)
No description available.
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En jämförelsestudie mellan regelsystem och pelar-balksystem / A Comparative Study between Timber Frame System and Column-beam SystemRezaei, Hamid January 2022 (has links)
Sverige antog ett klimatpolitiskt ramverk med målet att år 2045 ska Sverige inte ha några nettoutsläpp av växthusgaser till atmosfären. Klimatets påverkan från byggsektorn i Sverige står idag för närmare 21 procent av totala utsläppen. Klimatpåverkan från nybyggnation uppkommer främst under byggskedet och den är lika stor som påverkan från byggnadens energianvändning under 50 år. Mer än halva klimatpåverkan i byggprocessen är orsakad av tillverkningen av betong. För att kunna minska utsläppen från byggsektorn krävs att börja utnyttja förnyelsebara råvaror för en hållbar utveckling. Trä är ett miljövänligt alternativ och bör användas i större utsträckning än det görs idag. Man kan även använda trä i hela byggnationen men det finns en del av bygget till exempel grunden som är svårt att ersätta med andra material än betong på grund av betongens goda egenskaper. Förstärkningen i grundkonstruktionen blir utformad efter val av stomsystem. De vanligaste stomsystem som förekommer i träbyggnader är pelar-balksystem, missivträteknik och regelsystem (lättbyggnadsteknik). Målet med examensarbetet är att jämföra skillnaden mellan förstärkningar i två olika stomsystem. Jämförelsen kommer att genomföras för att kunna fastställa vilket stomsystem som använder minst betong och armeringar i förstärkningen och bästa ekonomiska alternativ. Rapporten delas in i två delar, den första består av teoretiska resonemang och den andra av beräkningar på pelar-balksystem. Därefter görs en jämförelse mellan mina beräkningar och de som redan finns gjorda av företaget Sjötorps Bygg gällande regelsystem. Till sist kommer resultatet att visa vilket stomsystem som är miljövänligast och mest ekonomiskt. / Sweden adopted a climate policy framework with the goal that by 2045 Sweden will have no net emissions of greenhouse gases into the atmosphere. The impact of the climate from the construction sector in Sweden today accounts for almost 21 percent of total emissions. The climate impact from new construction arises mainly during the construction phase and it is as great as the impact from the building's energy use over 50 years. More than half of the climate impact in the construction process is caused by the production of concrete. To be able to reduce emissions from the construction sector, it is necessary to start using renewable raw materials for sustainable development. Wood is an environmentally friendly alternative and should be used to a greater extent than is done today. You can also use wood throughout the construction, but there is a part of the construction, for example the foundation, which is difficult to replace with materials other than concrete due to the good properties of the concrete. The foundation in the basic construction is designed according to the choice of frame system. The most common frame systems that occur in wooden buildings are column-beam system, panel system of solid wood and timber frame system The aim of the degree project is to compare the difference between foundations in two different wood systems. The comparison will be carried out to be able to determine which frame system uses the least concrete and reinforcements in the foundation and the best economic alternatives. The report is divided into two parts, the first consists of theoretical reasoning and the second of calculations on the column-beam system. Then a comparison is made between my calculations and those that have already been made by the company Sjötorps Bygg regarding load-bearing systems. Finally, the results will show which system is the most environmentally friendly and most economical. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>
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Akustiska värden i platonkonstruktioner : Minimera lågfrekvent buller i skolmiljöer / Acustic values in platon construction : Minimizing low frequency noise in school environmentsFranzén, Henny, Elmondt Nilsson, Carl January 2019 (has links)
I denna studie har man fokuserat på hur omfattande ljudnivåerna kan vara på ett så kallat flytande golv. Det har fördjupats i konstruktioner med Platonmatta för att få en uppfattning om hur de akustiska faktorerna yttrar sig när någon beträder golvet. Studien jämför resultat av steg- och trumljudnivåer med Granabkonstruktioner, som är en annan typ av flytande golv, samt hur Platonkonstruktionen står sig i förhållande till de lagstadgade riktvärdena. I denna studie har det fokuserats på hur ljudet uppfattas både objektivt och subjektivt eftersom mätvärden i vissa fall inte stämmer överens med den faktiska upplevelsen. Golvtesterna som genomförts har gett oss mätvärden och en objektiv upplevelse. Detta har resulterat i en optimal golvkonstruktion teoretiskt. Sammantaget visar denna studie att golvens konstruktion i stor utsträckning kan minimera steg- och trumljud. Alla Platonkonstruktioner som testats i studien har generellt gett bra akustiska värden för att vara ett överliggande golv. Den kunskapen kan vara till stor nytta när man projekterar ett flytande golv eftersom höga ljudnivåer i de lägre frekvenserna har visat sig påverka bland annat inlärnings- och koncentrationsförmågan. / This study highlights the intensity and the extent of sound levels produced by a so called floating floor. The study has closely observed floor constructions made of Platon mat in order to detect the acoustic factors and how they are manifested when stepping on the floor. The study also compares the results of step- and drum sound levels with Granab constructions, another type of floating floor, as well as how the Platon construction stands in relation to the statutory guide values. This study has focused on how the sound from a Platon floor is perceived in an objective and a subjective perspective, because in some cases measured values do not correspond to the actual experience. Measurements that have been carried out give an idea of how to design floors and what type of material should be used to obtain the most favorable sound level possible. Overall, this study shows that the design of the floors can, to a large extent, minimize step- and drum sounds. This knowledge can be of great use when designing a floating floor since it has been shown that high sound levels in the lower frequencies affect, among other things, our abilities of learning and concentrating. / Akustik, platongolv.
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Normalförbrukning i villa : Explosioner i byggnaderLivfors, Mattias, Pettersson, Marcus January 2014 (has links)
Denna uppsats behandlar projektering av ett småhus i form av framställande av system och konstruktionsritningar som följer Boverkets byggregler. Den innefattar även val av material för utvalda delar av småhuset där hänsyn tagits till väsentliga parametrar. För att framställa godkända ritningar har beräkningar utförts för att kunna bestämma tillräckliga dimensioner på ventilation, värme, sanitet och konstruktion. Slutligen har även en kostnadskalkyl utförts för att analysera totalkostnad och driftskostnader för småhuset. Detta är fördjupningsdelen i ett arbete som också innefattar projektering och dimensionering av ett småhus.
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Design of concrete pavements : design criteria for plain and lean concreteSöderqvist, Johan January 2006 (has links)
New road infrastructure projects are important and constitute of large investments that have to serve the society for a long time. The investments have to be durable at the lowest life cycle cost and the pavements have to sustain loads from increasing traffic intensity and heavy traffic loads. In Sweden less than 1 ‰ of the national road network consists of concrete pavements. In parts of Europe and in the U.S., on the other hand, concrete roads are used to a large extent for highways as well as rural roads. To encourage the competition between different road materials in Sweden, the tools for designing robust concrete pavements have to be brought forward. In order to emphasize plain concrete pavements as an alternative in road construction, the design must also be competitive. The current Swedish design method for concrete pavements is straightforward but offers no flexibility when designing roads with, for instance higher traffic loads. The method calculates concrete thicknesses on the conservative side since only a limited number of parameters are treated. Modern methods that take into account many more parameters in the design are being developed internationally. For a new Swedish design method, these parameters have to be established for actual conditions in Sweden. Also, the design has to be flexible and meet the demands from contractors and clients for a wider use. The aim of this project is to develop a new design method for plain concrete pavements that is more flexible than today. A new design method is also intended for the Swedish Road Administrations’ (SRA) computer based public design guide, PMS Objekt. Information for a new design method has been assembled mainly by investigating two newly developed design methods, VENCON2.0 in the Netherlands, and the Mechanistic-Empirical Pavement Design Guide (MEPDG) in the USA. Comparative calculations between the Swedish design method and the MEPDG are presented. The comparison is made on the level of input parameters and highlights the advantageous aspects of a semi-mechanistic design procedure where the functional properties of a concrete pavement are calculated incrementally over the design period. Plain and lean concrete, separately, but also the in composite beams, have been studied in flexural fatigue testing. The results show that Tepfers’ fatigue criterion is valid for both plain and lean concrete when subjected to flexural fatigue loading. The results also show that the fatigue strength of composite beams of plain and lean concrete is mainly dependent on the strength of the lean concrete but that Tepfers’ fatigue criterion is applicable. The bond between plain in lean concrete is found to be strong and fatigue resistant, making the composite section able to accommodate higher stresses. The bond nevertheless contributes to the risk for reflection cracks in the plain concrete wear layer and a recommendation to focus on stresses in the bottom of the lean concrete is formulated. Also, well distributed expansion joints in the lean concrete are necessary. A new project for measuring temperature gradients for use in concrete pavement design is also presented. This is done with means of concrete prisms placed in the pavement and are done in order to establish actual temperature gradients for various locations in Sweden. Also, the nonlinear gradients that act in the pavement as well as the negative temperature gradients will be analysed for the use in the design. Finally, the thesis outlines a new design method for Swedish conditions. The method is possible to develop gradually and is based on FE-analysis for fast computations. In the design, stresses from traffic and temperature loads are calculated simultaneously in a number of critical locations in the concrete slab. The method will also make it possible to alter design features as slab lengths and widths, with various connections between the slabs. / QC 20101130
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Efficient production of high-rise buildingsHoseini, Hanif January 2007 (has links)
Production of one family houses has over time developed successfully in Sweden and producers have managed to reduce the production costs and industrialize the production process. The development has however not been that successful when it comes to high-rise buildings. There are many attempts made, but no one has really managed to create a product that can persuade the market. The systems used are not flexible and cannot cope very well with variations in the design. The aim of this work has been to develop and evaluate the idea of prefabricated high-rise buildings within the outlines of a scientific research. By understanding the problems that the building sector experiences today it will be possible to identify the solutions that are needed tomorrow. The main objective has been to develop new technologies and system concepts for buildings. Concepts that are highly flexible and respect the ambitions of the architect and technologies that will facilitate a more effective building process and address relevant key issues in building physics and building construction for cost reduction and a sustainable performance. Aside from the actual production cost it is also important to consider the lifecycle cost of the building. The production cost represents only a fraction of the total lifecycle cost of a building. A background research has been made to understand the building process and its problems, this information served for the formulation of a building concept. The work has been interdisciplinary and has not been limited to only one single point of view. Because of the nature of the method the work has resulted in new construction techniques. The initial idea of the prefabricated high-rise building has during the course of this work developed to a complete building concept. The Symphony Concept as it is called is about industrial prefabricated buildings that are assembled on site and is based on the idea of large and flat building elements with a very high degree of prefabrication. To evaluate the concept technology detailed researches have been made in different fields. The detailed researches made in this thesis regards the strength of sheet metal studs embedded in stiff insulation blocks, hazards connected with plastering on light weight constructions and fire protection of light weight constructions. The experiences from these researches are then applied in the building concept. Theory was put to practice with the construction of an experimental building called the Research Tower. The purpose of this pilot-project was primary to evaluate the construction technology and secondary to evaluate the properties of the building concept. To be able to find methods for production of sustainable, cost-effective and attractive high-rise buildings it is necessary to have a holistic view. A holistic concept that takes into consideration the whole building process will yield time- and cost-efficient production while it will also make it possible to achieve better quality. The detail researches shows that embedding of the sheet metal profiles in the rigid insulation blocks will increase the buckling load of the stud and that the thickness of the plastering layer and the material properties of its substrate will affect the strains in the plastering layer and the moisture stored in it. Regarding the fire protection it could be stated that the Symphony outer wall construction protected with a double layer of gypsum board can maintain segregation of the fire up to 60 min as long as the gypsum boards do not crumble. In the production of the pilot projected it could be stated that the fact that the whole building was designed by one homogenous team with information about all details, made it possible to foresee many problems. The production of elements even in the temporary experimental production facility proved to be fast and economic, even with untrained labour force and the elements could be prefabricated to a very high level with facades that are plastered before assembly. / QC 20101108
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