<p>Genom vår utbildning till belysningsvetare vid avdelningen för Belysningslärapå Tekniska Högskolan Jönköping har vi kommit i kontakt med standard SSEN12464-1. En standard som specificerar belysning för offentligainomhusmiljöer. Det vi fått lära oss under utbildningen stämmer inte överensmed vad standarden säger, vi har därför formulerat följande frågeställningar isyfte att undersöka denna skillnad.</p><p>· Hur väl uppfyller den europeiska belysningsstandarden den svenskaarbetsmiljölagens intentioner vad gäller belysning?</p><p>· Kan man uppnå arbetsmiljölagen intentioner med en standard?</p><p>Genom litteraturstudier och intervjuer har vi undersökt området kring dessafrågeställningar. En analys har genomförts där vi genom jämförelser av intervjuutlåtande och litteratur har fått fram ett resultat.Vi har funnit att det finns meningsskiljaktigheter mellan belysningsteknikenoch belysningsvetenskapen om hur belysning skall planeras och hur man skallkontrollera den. Belysningstekniken menar att fysikaliska mätvärden är säkrareatt utgå ifrån då dessa är objektiva medan belysningsvetenskapen hävdar attman inte kan utvärdera en visuell miljö med fysikaliska mätvärden.Den slutsats vi kom fram till är att standarden har svårigheter att uppfyllaarbetsmiljölagen. Standarden lever inte upp till arbetsmiljölagens krav påergonomi, standarden saknar koppling till rummet och brukaren enligt vårslutsats. Vi kom samtidigt fram till att en standard nödvändigtvis inte behövervara ett dåligt utgångsmaterial för belysningsplanering. Däremot bör denversion som används idag starkt omarbetas då den saknar koppling till rummetoch brukaren.</p> / <p>In our education to become Lighting designers at Jönköping University at theDepartment of lighting Science we have come in contact with standard SS-EN12464-1. The information we have acquired during our education does notcomply with the information contained in the standard. We decided toinvestigate:</p><p>· How well the European lighting standard SS-EN 12464-1 does respondto the intentions of the Swedish work environmental act?</p><p>· If it´s possible to secure the intentions of the work environmental act´sintentions with a standard?</p><p>We have investigated this issue through studies of literature and interviews. Aresult has been reached through comparisons of literature and interviews.We found that there are differences between lighting technology and lightingscience when deciding on how lighting should be planned and how it´s qualityshould be secured. Lighting technology argue that it´s safer to use photometryas it´s more objective, meanwhile lighting science argue that you can’t evaluatea visual environment with instruments.Our conclusion is that the standard has difficulties fulfilling the workenvironment act. The standard fails to fulfill the demands specified in the workenvironmental act´s demands for ergonomics; it lacks the connection to userand space according to our conclusion. At the same time we reached theconclusion that a standard is not necessarily a bad starting point when planninglight. However the version currently in use needs to be strongly revised as itlacks the connection to user and space.</p>

<p>Munksjökajen is an old industrial estate on the western shore of Munksjön in Jönköping. The purpose of this thesis is to develop Munksjökajen in accordance with the program for Jönköping’s future development – Stadsbyggnadsvisionen – drawn up by the city council.</p><p>Munksjökajens relations to the surrounding areas have been investigated as well as the need for public transport and possibilities for commercial, municipal and private businesses to operate in the area.</p><p>The final proposal has a relatively high degree of preserved industrial buildings. New buildings vary in shape and expression in order to create an interesting and diverse environment. The proximity to the lake adds character to the neighbourhood and the water is accentuated by the integration of it in the area.</p>

<p>Today’s bridge design work in many cases demands a trustworthy dynamic analysis instead of using the traditional dynamic amplification factors. In this thesis a reliable 3D Bernoulli-Euler beam finite element model of the New Årsta Railway Bridge was prepared for thorough dynamic analysis using in situ bridge monitoring for correlation. The bridge is of the concrete box girder type with a heavily reinforced and prestressed bridge deck. The monitoring system was designed for long term monitoring with strain transducers embedded in the concrete and accelerometers mounted inside the edge beams and at the lower edge of the track slab.</p><p>The global finite element model used the exact bridge geometry but was simplified regarding prestressing cables and the two railway tracks. The prestressing cables and the tracks were consequently not included and an equivalent pure concrete model was identified.</p><p>A static macadam train load was eccentrically placed on one of the bridge’s two tracks. By using Vlasov’s torsional theory and thereby including constrained warping a realistic modulus of elasticity for the concrete without prestressing cables and stiffness contribution from the railway tracks was found. This was allowed by comparing measured strain from strain transducers with the linear elastic finite element model’s axial stresses. Mainly three monitoring bridge sections were used, each of which was modelled with plane strain finite elements subjected to sectional forces/moments from a static macadam train load and a separately calculated torsional curvature.</p><p>From the identified modulus of elasticity the global finite element model was updated for Poisson’s ratio and material density (mass) to correspond with natural frequencies from the performed signal analysis of accelerometer signals. The influence of warping on the natural frequencies of the global finite element model was assumed small and the bridge’s torsional behaviour was modelled to follow Saint-Venant’s torsional theory.</p><p>A first preliminary estimation of modal damping ratios was included. The results indicated that natural frequencies were in accordance between modelling and signal analysis results, especially concerning high energy modes. Estimated damping ratios for the first vibration modes far exceeded the lower limit value specified in bridge design codes and railway bridge dynamic analysis recommendations.</p>

<p>This thesis evaluates the performance of a deammonification system designed as a two-step tech-nology consisting of an initial partial nitritation followed by an Anammox process. Operation of a technical-scale pilot plant at the Himmerfjärden Wastewater Treatment Plant (Grödinge, Swe-den) has been assessed. Oxygen Uptake Rate (OUR) to evaluate the respiration activity of nitrifi-ers in the system and batch tests to assess reaction rates have also been applied in the study. It was found that the total inorganic nitrogen elimination strongly depended on the nitrite-to-ammonium ratio in the influent to the Anammox reactor, which was correlated with the per-formance of the partial nitritation phase. Therefore, a control strategy for oxidation of ammo-nium to nitrite has been proposed. Controlled oxygen supply to the partial nitritation reactor is obligatory to obtain a proper pH drop indicating oxidation of ammonia to nitrite at the adequate ratio. A very high nitrogen removal efficiency (an average of 84%) and stable operation of the system have been reached. Conductivity measurements were also used to monitor the system influent nitrogen load and the nitrogen removal in the Anammox reactor. The data gathered from the operation of the pilot plant enabled the use of multivariate data analysis to model the process behaviour and the assessment of the covariances between the process parameters. The options for full-scale implementation of the Anammox systems have been proposed as a result of the study.</p>

<p>Träbyggnandet i Sverige gick in i en ny era när myndigheterna beslutade att upphäva förbudet mot att bygga byggnader som är högre än två våningar. Denna förändring i lagstiftningen har bidragit till att utveckla träbyggandet under det senaste decenniet. Cross Laminerat Timber (CLT) har blivit erkänt som en ny teknik som använt på ett korrekt sätt ger starka och pålitliga konstruktioner. Materialet visar sig mer och mer intressant huvudsakligen beroende på den styvhet och styrka det visar i olika tester.</p><p>Ett av de projekt som använt CLT som bärande element är Limnologen i staden Växjö 500 kilometer söder om Stockholm. I detta projekt har både väggar och bjälklag med bärande delar av CLT använts. En av utmaningarna i samband med högre träbyggande är att beräkna och ta hänsyn till de vertikala förskjutningarna i stommen. Orsakerna till förskjutningen är momentana samt tidsberoende. I denna uppsats utvärderas dessa vertikala förskjutningar med två olika metoder. Den första av dessa är experimentell. Förskjutningarna mättes av en grupp forskare från Växjö universitet och utvärderas i denna rapport. Den andra är en Finit Element Modell där förskjutningarna simuleras beroende på parametrar som anses viktiga. Resultatet av simuleringen jämförs med de experimentellt erhållna värdena. Simulering är ett viktigt sätt att förutsäga förskjutningar i CLT byggnader i framtiden. Alla modeller har gjorts med hjälp av finita element programmet Abaqus.</p><p>FEM- modellen av Limnologen består av ett väggelement per våning i sex våningar. Detta element är det element där också förskjutningarna mätts på plats. På så sätt kan modell och verklighet jämföras. Förutom väggelement modelleras också bjälklagselement och kopplingen mellan vägg och bjälklag.</p><p>De experimentella resultaten har analyserats i programvaran Matlab. Resultatet blev ett antal grafer som redovisar förloppet. Det viktigaste resultatet är det som visar både den totala relativa förskjutningen samtidigt som den visar fuktkvoten i CLT- skivan. Fuktkvoten beräknades från temperatur och relativ luftfuktighet som båda mättes på plats.</p><p>Slutsatsen är att man med en simulering kan åstadkomma en acceptabel tillförlitlighet med avseende på vertikala förskjutningar. Krympningen har spelat en viktig roll för förskjutningarna. Den maximala förskjutningen som erhållits från mätningar var 21 mm medan det maximala förskjutningen fått från simuleringen baserad på tre olika antaganden var 35 mm, 33 mm och 17 mm. Skillnaden i resultaten kan delvis förklaras av de antaganden som använts för beräkning av fuktkvot och antagandet om fiberriktningen i timret. I simuleringen antogs fuktkvoten vara konstant över alla tre lager i CLT- skivan i de två första fallen. Orienteringen av fibrerna antogs radiell och tangentiell. Det tredje antagandet bygger på att fukten enbart påverkar det yttersta lagret i skivan. Detta antagande är rimligt på grund av tidsåtgången att uppnå fuktjämvikt och på grund av det limlager som skiljer lagren åt och hindrar fukt att vandra från ett lager till ett annat.</p> / <p>The history of timber buildings in Sweden entered a new era when the authorities decided to lift the ban on constructing more than two-storey timber buildings in Sweden. This change in legislations has contributed to the emergence of timber construction during the last decade. The Cross Laminated Timber (CLT) has become recognized as a new technology that used correctly in construction gives strong and reliable structures. The building material is gaining more credit day by day mainly due to the stiffness and strength it proved throughout the tests in projects where it was used.</p><p>One of the projects that used CLT as load bearing elements was Limnologen in the city of Växjö 500 kilometres south of Stockholm. In this project, a system of CLT floors as well as CLT walls has been used. One of the challenges related to medium-rise timber buildings in general is to calculate and take account of the vertical displacement of the whole building. The sources for the displacements are instantaneous elastic as well as time dependent. In this thesis we are introducing two evaluation methods for the vertical displacements in Limnologen. The first is the experimentally measured vertical displacement that was performed by a group of researchers from Växjö University, and the second is a Finite Element Model simulating the vertical displacement according to the factors and parameters thought to be important to be included in the modelling. The output of the simulation was to be compared with the experimentally obtained values. Simulation is an important way to predict the vertical displacement in future CLT buildings. All modelling were done using the finite element software Abaqus.</p><p>The Abaqus model of the Limnologen building consists of six wall elements from six storeys. The modelled wall elements are the wall elements that the vertical displacement devices were installed on. The reason for this is to get a better picture of how the results from the model would yield in comparison to the site measurements. The floor itself and the sylodyn used in the interface between wall and floor were also modelled.</p><p>The data collected from the site were processed in the software Matlab. Several graphs were attained out of the data processing. The most important graph is the one that include both the total relative displacement and the equivalent moisture content in the CLT. The equivalent moisture content was calculated from the measured temperature and relative humidity.</p><p>In this thesis it is concluded that a simulation can accomplish an acceptable reliability with respect to the vertical displacements. The shrinkage factor has played a vital role in simulation of the displacements. The maximum displacement obtained from the measurements was 21 mm while the maximum displacement gained from the simulation based on three different assumptions was 35 mm, 33 mm, and 17 mm respectively with the similar displacement pattern. The difference in the results can partly be explained by the assumptions used for the equivalent moisture content and local coordinate system of the CLT layers. In the simulation the moisture content was assumed to be equal over each layer of the CLT-panel. The first two assumptions were formulated due to the amphibolous grain of the middle layer of the CLT-panel which was considered having effect on the vertical displacement. The third assumption was formulated due to the glue layer between the wood layers of the CLT-panel which was considered having effect on preventing moisture diffuse from one layer to another layer. In reality it is questionable if the moisture content is varied in the different layers of the CLT-panel. The diffusion of the moisture content hasn't been taken into account.</p>

Munksjökajen is an old industrial estate on the western shore of Munksjön in Jönköping. The purpose of this thesis is to develop Munksjökajen in accordance with the program for Jönköping’s future development – Stadsbyggnadsvisionen – drawn up by the city council. Munksjökajens relations to the surrounding areas have been investigated as well as the need for public transport and possibilities for commercial, municipal and private businesses to operate in the area. The final proposal has a relatively high degree of preserved industrial buildings. New buildings vary in shape and expression in order to create an interesting and diverse environment. The proximity to the lake adds character to the neighbourhood and the water is accentuated by the integration of it in the area.

Construction is often defined as a project-oriented industry that develops complex one-of-a-kind products using an engineer-to-order (ETO) design process. The technical solutions that are developed in specific projects often have integral product architectures that are difficult to re-use in continuous improvement processes. The ETO process also means that very few components can be produced before being ordered, which is necessary for creating economies of scale in production. In contrast, Modify-To-Order (MTO) Configure-To-Order (CTO) or Select variant-To-Order (STO) design processes based on theories of mass customization reuse technical solutions from earlier projects to varying degrees. However, many researchers argue that results and theories from the manufacturing industry cannot be used in the contexts of construction because each construction project has different functional requirements and local site conditions whose interaction mandates the creation of unique end products that cannot be modularized as is done in manufacturing industries. The purpose of this thesis was to investigate how mass customization principles could be utilized in the design of construction products, especially how the adoption of platform architectures and configurators could support the reuse of technical solutions between projects. Several case studies of projects using different specification levels (MTO, CTO and STO) were conducted to test theories of mass customization in the context of construction. The results obtained show that when working at the MTO and CTO specification levels, platform architectures should be based on modules that can be developed incrementally. STO products can be developed with integral product architectures, but if the needs of customers in the target market segment change this presents a risk of ad-hoc end product customization that will adversely affect the production system downstream in the value chain. For all studied specification levels, it is important to determine whether the target market volume is sufficient to justify the cost of developing a product platform. The introduction of design modules in modular platform architectures enables the development and use of configurators in ETO construction design processes. Such tools allow MTO platforms to be customized using a mixture of traditional ETO design and the configuration of predefined modules. Configuration tools for module customization at the MTO and CTO levels must therefore be integrated with the traditional design tools used in construction. The configuration of modular platform architectures also facilitates the effective use of information and its transfer between domains. As the use of pre-defined modules in the product specification process increases, the need to involve multiple design disciplines decreases. At the STO level, the design work can be reduced to such an extent that customization can be achieved using web-based configurators.Overall, the results presented in this thesis indicate that the Products in Product mass customization concept introduced by Erixon (1998) can be implemented at multiple specification levels in the traditional design of construction products. By introducing the new design module category into the platform architecture, predefined construction product platforms can be integrated with the traditional ETO design process and developed incrementally. / Construction is often defined as a project oriented industry developing complex one-of-a-kind products in an engineer-to-order (ETO) driven process by temporary organizations. That is resulting in a fragmented design process with loose connection between different disciplines. Many studies indicate that the early stages of product development is critical for product constructability, but technical solutions that are developed in specific projects lead to integral product architectures that are difficult to re-use in a continuous improvement process. The ETO process also means that very few components can be produced before ordering, a prerequisite for creating economies of scale in production. By changing the product realization process to "modify- to-Order" (MTO), "configure- to-order" (CTO) or "select variant" (STP), which is based on the theories of mass customization, technical solutions can be reused between the specific projects. However, several researchers in the construction industry proclaim that the contexts of construction industry cannot be compared with other industries and products. The variation of interacting functional requirements creates unique end products that cannot be separated in similar way as in the manufacturing industry. Arguments are based on the uniqueness of the end products that is analysed with regards to the highest level in the product architecture, which is why a more nuanced view is required.Mass Customisation can be described as an approach to combine economies of scale from mass production with increased customization for the end customer. To successfully achieve this, the generic product architecture need to be based on a modular architecture with clear separation between functional requirements (FR) and design parameters ( DP) and well-specified interfaces between the modules. Selected market segment affects the demand for product customization relatively the order point and thus affects its product realization process; MTO, CTO and STP, whereupon the selected specification level also affects the generic product architecture with its product platform and how the customization can be done. The purpose of this thesis is to describe whether and how mass customization can be used in the construction industry by describing the relationships between product architectures and the specification levels.Several case studies in the specification levels MTO, CTO and STP have been made based on theory of mass customization. The case studies have been performed in a deductive approach where theories have been tested in real cases and validated through experiments. Results from the cases have improved the understanding in this area and been used in following case studies, why the thesis as a whole can be described as abduction.Research results shows that in the MTO and CTO specification level, product platforms should be based on modules that can be developed incrementally. STP products can be developed with integral product architecture, but if changes in the customer segment occur there is great risk that production will be affected negatively. In all studied specification levels, it is important to understand the market segment volumes to justify the development costs. Introduction of "Design variant module" for modular systems means that configurators for subsystems can be developed. Customization of MTO platforms then consists of a mixture of traditional design and configuration of modules. But to accomplish this, the link between ICT tools in the MTO and CTO process needs to be connected with traditional ICT tools in the construction industry. However, using modular product architectures in the design greatly reduce the information exchange between disciplines. If STP products are developed customization can be done using a web interface.In conclusion, if using the "Products in Product" concept (Erixon, 1998) it is possible to implement theories from mass customization in construction. It is also seen that modular product architecture creates opportunities to repair information chains and minimizes the exchange of information between different disciplines, enabling the use of ICT tools developed in other industries. By introducing a new module category to the existing theory, namely "Design variant module", the traditional design process (ETO) can be coupled with predefined product platforms and develop incrementally. / Godkänd; 2014; 20140416 (patjen); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Patrik Jensen Ämne: Byggproduktion/Construction Engineering Avhandling: Configuration of Platform Architectures in Construction Opponent: Professor Lars Hvam, Department of Management Engineering, Technical University of Denmark, Lyngby, Denmark Ordförande: Professor Thomas Olofsson, Avd för byggkonstruktion- och produktion, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Tid: Tisdag den 17 juni 2014, kl 13.00 Plats: F1031, Luleå tekniska universitet

Value and waste are concepts that are used in improvement projects. In lean the concepts are fairly simple. Reduce the waste and the value has increased. However, value is both multidimensional and differs over time. If the concepts value and waste are to be used, the concepts must be clearly defined and measured. Otherwise, value can be reduced for the customer/user and the cost increased for the producer/seller. The purpose in this thesis is to investigate how value and waste are perceived by different stakeholders, how value and waste are related, and how value and waste are measured. The focus of the study is the improvement of production and services. The study does not investigate the product/service development. The conclusions are based on a number of cases and research from different fields such as resource-based view and marketing. The study use mix of qualitative and quantitative methods. Measures of forecasting accuracy and their relations where explored with different statistical tools in order to understand the influence of measures and dimensions. The view of value concerning energy efficiency was examined in a statistical analysis of a survey concerning stakeholders’ view of a specific value, energy efficiency, as well as their influence on the value creation process. A multiple qualitative case study explores the relation between value and waste in different settings and the consequences of waste focus. The findings in the multiple case study are confirmed and elaborated further by an additional case study, both qualitative and quantitative, of value stream mapping.Value and waste are analysed with the use of order winners and qualifiers. Also, a model to clarify the consequences of mixing value creation and value exchange for customer/user and producer/seller have been defined and used in the analysis.Depending on the stakeholder there is a difference between whether value can be regarded as a use value, exchange value or both. Even if exchange value is related to a specific moment in time, use value is not. The view of value differs among stakeholders which increase the risk of sub-optimisation in production.Value and waste have multi-dimensional properties and there are links between the different dimensions. The relationships depend upon the situation in question. The lean seven types of waste are not independent dimensions. Also, the concept of waste as anti-value is too simplistic. In all cases studied the focus is on waste, not value. Also, it is often the symptoms of waste that are of interest in measures taken not the root causes. Reduction of waste without considering the value can create new waste. Since waste is a dependent variable, it should not be measured without considering value. Another complication is that value and waste often occurs at different points in time and in different settings.Single measures are sensitive to its environment. Several measures are more robust. Measures distort and influence the perception and thereby the decision of the studied phenomena. Also, the notion of value and waste becomes harder to define and trace as the resolution and detailing of the studied process increases. / Godkänd; 2016; 20151028 (petwal); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Peter Wallström Ämne: Byggproduktion /Construction Engineering and Management Avhandling: On Value and Waste Opponent: Docent Kristian Widén, Avd för Byggproduktion, Institutionen för Byggvetenskaper, Lunds tekniska högskola, Lund. Ordförande: Professor Ove Lagerqvist, Avd för byggkonstruktion och -produktion, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet, Luleå. Tid: Onsdag 14 september, 2016 kl 13.00 Plats: F1031, Luleå tekniska universitet

<p> </p><p>The aim of this Master Thesis is to assess the load carrying capacity of the Glomman Bridge outside of the Swedish city Örebro. The Glomman Bridge is an unreinforced concrete single span arch bridge with backfill. The bridge was constructed in 1923 on assignment from the Swedish National Railways (SJ).</p><p>The failure criteria used in this thesis is that the bridge collapses when any cross section in the concrete arch reaches its ultimate capacity. In reality, the bridge may manage heavier loads than this. When the capacity is reached in a cross section, a hinge is formed and the arch relocates the forces to other parts of the arch that can carry higher stresses. The real bridge will not collapse until a fourth hinge is formed, and by that a mechanism. To be able to calculate the cross section forces in the arch, it was necessary to know the influences of the loads on the arch when they were run along the bridge. For this purpose, influence lines were obtained from a 2D finite element model created in ABAQUS, a general FE-analyses software. A calculation routine to find the least favourable load combination was then created in Matlab, a numerical calculation software. The routine was made to find the worst case among different load cases and to combine the standardized axle pressures with the present number of axles.</p><p>A parametric survey was also performed because the material properties for the different parts of the bridge are very uncertain. In the survey, the initial values were changed one at a time to study the outcome on the load factor. The load factor is the ratio between the ultimate limit load and the actual load. The studied parameters are the compressive strength, the Young's modulus, the density and the Poisson's ratio of the different parts of the bridge. The parameters are studied individually irrespective of possible correlation. The studied parts of the bridge are the backfill, the arch, the abutments and the asphalt. The clearly most important component is found to be the backfill. With increased stiffness or increased Poisson's ratio in the backfill follows increased load factor.</p><p>The equations behind the failure envelope can be derived from equilibrium equations for the unreinforced cross section. The influence lines are normalised with respect to the capacity of the cross section to get the degree of efficiency along the whole length of the arch, instead of the common influence lines that give the cross section forces. This is done because the failure is not caused by large cross section forces but by an exceeded ultimate stress. As the different loads are run along the bridge, the largest positive and negative efficiency for bending moment and normal force are localised. The normalised cross section forces are plotted together with the failure envelope and the load factor is then calculated.</p><p>Several masonry arch bridges were loaded until collapse in a study performed by the British Transport and Road Research Laboratory. One of the bridges in the study, the Prestwood Bridge, has been used in this thesis as a comparison to the Glomman Bridge. The load carrying capacity of the Prestwood Bridge is known, and is used to verify that the method using the failure envelope is applicable.</p><p>To compare the results from the cross section analysis from the failure envelope model to another method, the Glomman Bridge and the Prestwood Bridge were also tested in the commercial software RING 2.0. The method used in RING 2.0 differs from the failure mode in this thesis by calculating the load factor when four different cross sections reach their capacity and the bridge collapses.</p><p>The failure envelope method allows an A/B-value (Axle- and Bogie load) of 102 kN/147 kN when using very poor values of the parameters and 181 kN/226 kN when using a reference case with normal parameters.</p><p>Although the load capacity is found to be acceptable, the uncertainties are still large. To get a more accurate apprehension of the condition of the actual bridge, further research should be carried out, such as e.g. a non-linear model.</p> / <p>Syftet med föreliggande examensarbete är att uppskatta bärförmågan hos bron Glomman utanför Örebro. Glomman är en oarmerad betongvalvbro i ett spann med ovanliggande jordfyllning. Bron byggdes 1926 på uppdrag av Statens Järnvägar (SJ).</p><p>Brottkriteriet i detta examensarbete är att bron går till brott när något tvärsnitt i betongbågen uppnår sin kapacitet. I själva verket är det möjligt att bron kan klara tyngre last än detta. När kapaciteten nås i ett tvärsnitt uppstår en led och bågen omlagrar krafterna till andra bågdelar som klarar större spänningar. Den verkliga bron rasar inte förrän en fjärde led har utvecklats, och därmed en mekanism. För att kunna beräkna tvärsnittskrafterna i bågen, var det nödvändigt att känna till trafiklasternas påverkan på bågen när de kördes över bron. För detta ändamål erhölls influenslinjer från en tvådimensionell finita elementmodell skapad i ABAQUS, ett generellt FE-program. En beräkningsrutin för att finna värsta tänkbara lastkombinering skapades i Matlab, ett numeriskt beräkningsprogram. Rutinen utformades för att hitta värsta fallet bland olika lastfall samt för att kombinera standardiserade axeltryck med det aktuella antalet axlar.</p><p>En parameterstudie utfördes också då materialegenskaperna för de olika delarna i bron är mycket osäkra. I parameterstudien ändrades ingångsvärdena ett åt gången för att studera utslaget på lastfaktorn. Lastfaktorn är förhållandet mellan brottgränslasten och den verkliga lasten. De parametrar som studeras är tryckhållfastheten, <em>E</em>-modulen, densiteten och tvärkontraktionen för de olika brodelarna. Parametrarna studeras enskilt utan hänsyn till eventuell korrelation. De brodelar som studeras är fyllningen, bågen, fundamenten och asfalten. Den klart viktigaste komponenten visar sig vara fyllningen. Med ökad styvhet eller ökad tvärkontraktion i fyllningen följer ökad last­faktor.</p><p>Ekvationerna bakom brottenveloppet kan härledas ur jämviktsekvationer för det oarmerade tvärsnittet. Influenslinjerna normeras med avseende på tvärsnittets kapa­citet för att få ut utnyttjandegraden längs hela bågen. Detta görs då det egentligen inte är för stor tvärsnittskraft som orsakar brott utan för stor spänning. Högsta och lägsta utnyttjandegrad för böjande moment och normalkraft lokaliseras när de olika typlasterna körs över bron. Utnyttjandegraderna placeras i brottenveloppet för att sedan räkna fram en lastfaktor.</p><p>Ett flertal liknande broar har lastats till brott i en studie genomförd av British Transport and Road Research Laboratory. En av broarna i studien, Prestwood Bridge, har använts i denna rapport som jämförelse med Glomman. Då bärförmågan hos Prestwood Bridge är känd används den till att bekräfta att metoden med brott­enveloppet är tillämpbar.</p><p>För att jämföra resultaten från tvärsnittsanalysen i brottenveloppmetoden med en annan metod, testades även Glomman och Prestwood Bridge i det kommersiella programmet RING 2.0. Metoden som används i RING 2.0 skiljer sig från brottmoden i denna rapport genom att istället beräkna lastfaktorn när fyra olika tvärsnitt har uppnått sina kapaciteter och bron kollapsar.</p><p>Metoden med brottenvelopp tillåter ett A/B-värde (Axel- och Boggitryck) på 102 kN/147 kN när mycket dåliga parametervärden används och 181 kN/226 kN när referensfallet med normala parametervärden används.</p><p>Även om bärförmågan kan anses vara acceptabel är osäkerheterna stora. För att få en nogrannare uppfattning om brons faktiska tillstånd bör fortsatta studier utföras, som t.ex. en icke-linjär modell.</p>

<p>The sales of Ground Source Heat Pumps in Sweden and many other countries are having a rapid growth in the last decade. Today, there are approximately 360 000 systems installed in Sweden, with a growing rate of about 30 000 installations per year. The most common way to exchange heat with the bedrock in ground source heat pump applications is circulating a secondary fluid through a Borehole Heat Exchanger (BHE), a closed loop in a vertical borehole. The fluid transports the heat from the ground to a certain heating and/or cooling application. A fluid with one degree higher or lower temperature coming out from the borehole may represent a 2-3% change in the COP of a heat pump system. It is therefore of great relevance to design cost effective and easy to install borehole heat exchangers. U-pipe BHEs consisting of two equal cylindrical pipes connected together at the borehole bottom have dominated the market for several years in spite of their relatively poor thermal performance and, still, there exist many uncertainties about how to optimize them. Although more efficient BHEs have been discussed for many years, the introduction of new designs has been practically lacking. However, the interest for innovation within this field is increasing nowadays and more effective methods for injecting or extracting heat into/from the ground (better BHEs) with smaller temperature differences between the heat secondary fluid and the surrounding bedrock must be suggested for introduction into the market.</p><p>This report presents the analysis of several groundwater filled borehole heat exchangers, including standard and alternative U-pipe configurations (e.g. with spacers, grooves), as well as two coaxial designs. The study embraces measurements of borehole deviation, ground water flow, undisturbed ground temperature profile, secondary fluid and groundwater temperature variations in time, theoretical analyses with a FEM software, Distributed Thermal Response Test (DTRT), and pressure drop. Significant attention is devoted to distributed temperature measurements using optic fiber cables along the BHEs during heat extraction and heat injection from and to the ground.</p> / QC 20100517 / EFFSYS2 / Efficient Use of Energy Wells for Heat Pumps