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Glasfasader för trämoduler / Glass facade for a modular wood constructionCederwall, Linnea January 2018 (has links)
Sammanfattning Modulbyggnader har utvecklats mycket under de senaste decennierna. Metoden föredras på grund av de snabba monteringstiderna och enkla installationerna. I Sverige föredras trä som bärande material för modulerna. Modulbyggnader kan många gånger upplevas som repetitiv på grund av dess återkommande fasad. Glasfasader kan användas för att säkerställa en arkitektonisk uppfattning och bryta det repetitiva mönstret. Syftet med examensarbetet är att undersöka hur en glasfasad med en struktur av glas och trä kan användas med en modul. Fasaden är konstruerad för att produceras industriellt och enkelt monteras ihop med andra fasadelement. Värmeförhållanden och vindbelastning antogs efter en placering i Luleå. Tjockleken på det yttre glasskiktet har utformats efter lastkombinationer, där vindtrycket var den dominerande kvasistatiska belastningen. De påfrestningar som glasskiktet utsätts för har beräknats både analytiskt och med Finita elementmetoden. Fasadelementet består av tre glasskivor och en träram. Den yttre glasskivan är laminerad och är 14,8 mm tjock. De andra två är härdade glasskivor med en tjocklek av 4 mm vardera och två luftspalter på 18,5 mm mellan glasskikten. De härdade glasen är behandlade med ett lågemissionsskikt. Fasadens U-värde beräknades till 0,68 W / m2K med hjälp av programmet Spectrum. Laminerat trä används för träramen och löper runt glasskivans fyra kanter. Varje del av ramen är utformad som en U-balk med en längd på 3 meter. Fasadelementen är anslutna till trämodulen med 8x300 mm skruvar genom U-balken. Livets tjocklek på U-sektionen dimensionerades för att undvika sprickbildning på grund av borrning och fick dimensionen 88 mm. U-balkens övre och undre fläns är 100 mm bred och har en tjocklek av 20 mm. Deras syfte är att hålla glasplattorna på plats. Mellan glaset och flänsen appliceras ett akrylatlim som förbinder materialen. / Abstract Modular construction has significantly developed in the past few decades. The method is preferred due to the quick assembly times and ease of installation. In Sweden, wood is preferred as structural material for the modules. However, modular construction can be aesthetic due to its repetitive façade. Glass facades could be used to ensure an architectonic appeal and break the repetitive pattern. The purpose of the thesis is to investigate how a glass facade can be used in a modular structure using glass and wood. The façade is designed to be industrially manufactured and easily assembled with other facade elements. The thermal conditions and wind loads were asessed assuming that the building will be constructed in Luleå. The outside glass layer thickness has been designed from the load combinations in which the wind pressure was the dominant quasi-static load. The stresses to which the glass layer is exposed has been calculated both analytically and with the finite element method. The facade element consists of three glass layers and a wooden frame. The outside glass plate is laminated and is 14.8 mm thick. The other two are tempered glass plates with a thickness of 4 mm each and two air slots of 18 mm between the glass layers. The tempered glass is treated with a low-emission layer. The U-value of the facade was calculated to be 0.68 W/m2K using the software Spectrum. Laminated wood was used for the wooden frame and goes around the four edges of the glass plates. Each section of the frame is designed as a U-beam with a length of 3 meters. The façade elements are connected to the wooden module with 8x300 mm screws through the U-beam. The web thickness of the U-section was dimensioned to avoid cracking due to drilling. The top and bottom and flange of the U-beam is 100 mm wide and has a thickness of 20 mm. Their purpose is to hold the glass plates in position. Between the glass and the flange, an acrylate adhesive is applied that connects the materials.
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Versioning of IFC-based information models for collaborative designJaly Zada, Aras Jalal January 2016 (has links)
The engineering design process is an iterative and distributed process. It is often characterized by multi-disciplinary teams in multiple places working together, on a single project, using different models and software tools. The current collaboration approaches in AEC industry often focus on integrating and managing multiple models from multi-designers. Building Information Modelling (BIM) is playing a major role in facilitating collaboration. BIM provides an opportunity to electronically model and manage the vast amount of information embedded in a building project, from conception to completion. In the design process, changes in the models are inevitable and very common. They can occur at any stage of the project, from different sources, and for various reasons, which can have significant effects on the process. Versioning is a solution for design change management. Many model versions can be created and distributed among the disciplinary teams. Despite many researches done on the subject and the availability of some software applications that deal with changes in design, the mechanism to cope with the changes among different model versions needs further studies to increase the management efficiencies and ensure designers have an up-to-date version of the model. The challenges of information exchange in project management result from: a combination of the enormous amounts of information generated, the large variety of design systems involved, and data format utilised by different disciplines at various design stages. The Industry Foundation Classes (IFC) standard represents a paradigm shift for data and information exchange. The main goal for developing the IFC model is to provide a neutral data format to exchange information among different software programs. IFC models reflect the current state of BIM model. They do not take into consideration the process and results of latest changes among different BIM users nor record the history of earlier changes. This research work therefore investigates how to improve the process of managing the design changes from different disciplinary models. This research developed a collaborative methodology to manage the design changes in different models. It tackles the challenges of the versioning process as a change management approach. This is done through extending the capability of the existing IFC schema to control and manage different design changes in different BIM models. The proposed extended IFC incorporates the changed information of the latest model version and provides the complete history of changes of all earlier model versions. A prototype system was developed in this research to implement and validate the extended IFC and to demonstrate using it to improve the management of the whole design process. The research process involved undertaking a literature review to identify knowledge gaps and challenges in the areas of the (design process, BIM, IFC, and change management). The research also investigated and analysed the IFC standard and identified two key requirements of extending the IFC and implementing the prototype. Further aspects of this research include developing a framework to facilitate a collaborative design, extending the existing IFC schema, designing and implementing the prototype based on the extension, and validating and evaluating the extended IFC and the prototype system. The research concludes that the extended IFC to handle versioning can effectively improve collaborative design. It addressed concepts involving comparing, storing, classifying, extending managing, versioning, exchanging, and sharing of modelling information in a collaborative way. The proposed process of managing design changes covered an important gap associated with current IFC models, which can be incorporated in future releases of the IFC standard.
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Analysis of large-scale gas explosion tests and assessment of potential impact on structuresShearer, Murray J. January 2003 (has links)
This document provides a framework for the assessment of gas explosion impact on structures. It shows how the probability of a structure achieving a predefined level of success in withstanding a defined gas explosion scenario may be calculated. The thesis opens with a general introduction to the need for assessing the impact of gas explosions in offshore installations. In the second chapter relevant literature regarding the existing theory and approaches used in assessment of gas explosions is reviewed. In particular, limitations of existing techniques are highlighted. The experimental data that is available to the author is also discussed. In the third chapter a set of objectives is defined. Meeting these objectives would allow many of the outstanding issues in gas explosion assessment, highlighted in chapter two, to be addressed. These objectives essentially define the need for assessment of explosions to relate to the impact upon the structure they engulf and that the impact is dependent not only upon the explosion but upon the structure so effected. The fourth chapter extends an existing technique of applying time-averaging windows to pressure-time histories from explosions. In this chapter, the importance of an approach to analysing explosions that relates directly to structural response is first established. An improved understanding of the effect of explosion parameters upon explosion magnitude is also made. The fifth chapter makes use of conventional signal analysis techniques to address weaknesses of time-averaging approach. These techniques allow a better relationship between identified structural response frequency and quantification of loading to be reached. These techniques also allow analysis of the explosion time history to be made in the frequency domain. Our understanding of the explosion parameters on explosion magnitude is again advanced. Whereas the fifth chapter allows analysis to be made in the frequency pressure domain, the sixth chapter shows how analysis can be made in the frequency-loading domain. This is achieved by assessing the impact of pressure-time histories on a simple oscillating structure, a single degree of freedom object. Of all the techniques developed, this is believed to be the most appropriate. In the seventh chapter we begin to apply the techniques developed by assessing, among other things, the inherent repeatability of an explosion and our ability to accurately predict the magnitude of the explosion. We start to generate a body of statistical data relating to accidental gas explosions. Chapter eight shows how the knowledge gained in previous chapters might be applied within a framework that is relevant to current practices in risk assessment. The framework selected is known as the limit state approach. It is shown how performance criteria for the structure undergoing gas explosions might be set and how the probability of the structure meeting these conditions might be assessed.
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Progressive collapse mitigation using CMA in RC framed buildingsPunton, Ben January 2014 (has links)
Mitigation of progressive collapse after an initial failure has become a primary concern of engineers in recent years. Often alternative load paths are sought to redistribute load from the damaged area. It has been recognised for some time that the omission of compressive membrane action (CMA), also termed ‘arching action’, can lead to a significant underestimation of load capacity. An investigation has been conducted to ascertain whether the additional load carrying capacity from CMA can provide an inherent alternative load path to aid robustness. A series of scaled specimens with industry standard detailing have been designed for an experimental investigation. Reinforced concrete elements were modelled in the double span scenario once an intermediate column has been removed. The test rig used allows the central support to be removed followed by the application of a point load applied at midspan; the system is determinate including measurement of the horizontal reaction. Subsequent to the flexural response two modes of membrane action are induced, initially compressive until tensile membrane extends load capacity at high values of deflection. The response during the latter tensile phase is outside the scope of this research. Comparisons of experimental data with analytical methods inclusive of CMA have demonstrated that whilst conservative the method by Merola (2009) provides a reasonable prediction. This method has been utilised in a study of a series of flat slab structures with a range of column spacings. The inherent restraint stiffness provided by the surrounding slab and frame has been quantified using FEA and has allowed for the extent to which CMA can improve the robustness of a structure to be determined.
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The thermal performance of foundation piles used as heat exchangers in ground energy systemsLoveridge, Fleur January 2012 (has links)
Pile heat exchangers are expected to make a significant contribution to meeting UK and EU renewable energy and carbon dioxide reduction targets. However, design for the thermal capacity of pile heat exchangers has to date been largely based on methods developed for borehole heat exchangers. Piles have a much smaller aspect (length to diameter) ratio than boreholes and consequently their thermal behaviour is different in a number of important ways. This thesis explores these differences and makes recommendations for improved assessment of pile heat exchanger thermal capacity. Traditionally vertical heat exchanger design assumes separation of the thermal effects in the ground and in the pile. A transient temperature response function is used to assess temperature changes in the ground and a steady state resistance is applied to the pile concrete. In this thesis existing approaches to temperature response functions are critically assessed for use with thermal piles. It is important to take into account the larger pile diameter, which causes increased temperature changes in the short term. In the long term, the shorter pile length will result in reduced temperature changes as steady state is reached more quickly. Simple 2D numerical modelling has been carried out and the results used to derive a new method for determining pile thermal resistance. However, for large diameter piles, the time taken for the pile to reach steady state suggests that the use of a constant thermal resistance in design is not always appropriate. In these cases it is recommended that a transient temperature response function is used to assess the response of the ground and the concrete together. The applicability of short duration thermal response testing for pile heat exchangers has been examined. Modelling and case study data has shown that the technique is only reliable for piles of 300mm diameter or less. For the special case of large diameter piles with centrally placed heat transfer pipes then it is possible to use the test to determine the thermal conductivity of the pile concrete, but not pile thermal resistance.
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The behaviour of modern flexible framed structures undergoing differential settlementSmit, Gerrit January 2010 (has links)
Modern office buildings are often open plan buildings with a frame consisting of flat RC slabs, RC columns and non-load bearing internal and external partitions and facades. These modern framed structures are more flexible than older conventional buildings with load bearing walls and are less susceptible to differential settlement damage. The use of conventional guidelines for differential settlement on modern flexible framed structures may therefore be over-conservative. The literature review of the study highlights the factors producing differential settlement, the types of damage caused by differential settlement and conventional guidelines for limiting differential settlement damage. Conventional guidelines focusing on 2D structures lack provision for the 3D deformation of a structure. To determine the behaviour of a modern flexible framed structure a numerical experiment was performed, which consisted of the design according to British Standards and Eurocodes of a 3D, 5-bay by 5-bay, 6 storey flat slab RC frame with pad foundations on clay. The behaviour of the designed structure undergoing differential settlement was then analysed by means of linear-elastic finite element analyses. The results show firstly that it is possible to normalise structural behaviour to the soilstructure stiffness ratio, secondly the importance of 3D deformation of the structure and thirdly that stiffer load-displacement responses of foundations may also affect the behaviour of the structure. A stiffer load-displacement response may occur with the reuse of foundations
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BDT-SYSTEM FÖR SPOLNING AV WC : En studie om utformning av system som återanvänder BDT-vatten / Greywater re-use for flushing toilets : A study on the design of a system that recycle greywaterJohannesson, Kristoffer, Petersson, Rasmus January 2018 (has links)
Syfte: Varje dag spolar vi ner ungefär 30 liter vatten i toaletten. Att det är rent dricksvatten som används i detta syfte är inte en hållbar lösning med hänsyn till den globala uppvärmningen och problemen den för med sig. I Sverige har vi redan sett tecken på vattenbrist och utvecklingen ser inte ut att gå mot det positiva. En bättre hushållning med vårt vatten är ett förslag på en mer hållbar utveckling gällande vattenförbrukningen och ett alternativ till ett sådant förslag beskrivs i denna rapport. Att lokalt kunna återanvända BDT-vatten till att spola toaletterna kan spara närmare 30 % av den totala vattenförbrukningen. BDT-vatten innehåller flertalet skadeämnen och för att denna återanvändning ska kunna ske måste det säkerställas att det inte medför några hälsorisker. Målet med arbetet är att skapa ett system med god teoretisk tillförlitlighet samt undersöka den ekonomiska hållbarheten av ett sådant system vid införandet i nybyggnation av ett flerbostadshus. Metod: För att uppnå detta mål har en omfattande litteraturstudie av BDT-vattnets karaktär samt befintliga system genomförts. Intervjuer med personer inom VVS-branschen samt personer med kunskap inom olika reningsmetoder har genomförts för att få en bredare kunskap i ämnet. Resultat: Rapporten beskriver utformningen av ett fysiskt system anpassat till nybyggnation av flerbostadshus med 30 lägenheter. Resultatet visar att det finns möjlighet till besparing av dricksvatten samt möjlighet till ekonomisk vinning vid återanvändning av BDT-vatten.Systemet har god teoretisk tillförlitlighet men författarna föreslår vidare forskning i form av empirisk prövning av systemets funktionsduglighet. Konsekvenser: Införandet av ett system som återvinner BDT-vatten innebär flera förändringar i det befintliga arbetssättet. Förändringar tar ofta lång tid att införa i den svenska byggbranschen. Trots detta hade implementeringen inneburit flera fördelar i införandet av ett sådant system, där en reducering i dagens dricksvattenanvändning är en av de viktigaste. Med dagens teknik kan man på ett pålitligt sätt rena BDT-vattnet till den grad då det inte är hälsoskadligt. Möjligheten till ekonomisk vinning bör motivera implementeringen av ett sådant system vid nybyggnation av större flerbostadshus. Begränsningar: Vi har endast sett till möjligheten att införa ett system i Sverige med lagar och regler som gäller här. Den ekonomiska aspekten baseras på nybyggnation av ett flerbostadshus.Endast BDT-vatten kommer att analyseras. Nyckelord: Ekonomisk analys, filter, hälsoskadliga ämnen i BDT-vatten, membranseparationrening av BDT-vatten.
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Visuell planering inom projekteringBäckman, Ellen January 2018 (has links)
No description available.
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KL-trä som stommaterial : Konstruktionssystem och effekter av fuktinverkan under produktionsfasenDimstrand, Daniel, Jansson, Felix January 2018 (has links)
No description available.
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Rectangular hollow sections with circular web openings : fundamental behaviour in torsion, bending and shearRidley-Ellis, Daniel January 2000 (has links)
The primary aim of the project was to develop the basis for a set of rules to be used in the design of RHS slim floor edge beams with web openings. However, since the research is fundamental in nature, the findings are also applicable to other situations where it may be advantageous to cut holes in load bearing tubular members of rectangular cross-section. The study considered the influence of the number and size of holes upon resistance and stiffness in bending, shear, and torsion and combined analytical Finite Element modelling with large and small scale pseudo-static (short-time static loading) laboratory testing. In all but one category of tests (see below), good agreement was achieved between experimentally measured quantities (such as capacities, deflections and strains) and the corresponding Finite Element predictions, allowing parametric investigations to be conducted with calibrated analytical models. Preliminary design recommendations are presented based on the results of the parametric study and laboratory tests. The design advice was developed with regard to existing recommendations for the design of perforated I-beams, and was produced in a form that allows integration with modern limit state design codes. Aspects of behaviour requiring further investigation have been identified and categorised. Torsion tests on full scale RHS without web openings yielded some unexpected results. Elastic and plastic capacities measured in the laboratory were significantly lower (12–20%) than those predicted by the Finite Element models and the thick walled torsion theory used as the basis of the British and European design procedures. Attempts were made to determine the cause of this behaviour and a number of possibilities were eliminated. Although the anomalous results have not been fully explained, evidence of similar behaviour in previous full-scale testing was discovered.
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