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  • 1.
    Abrahamsson, Caroline
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Waltersson, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    FLEXIBLA BYGGNADER: Utformning av en förskola med en möjlig verksamhetsändring för framtida behov2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Society today has an increasing demand for environmentally and economically sustainable developments in order to create a sustainable society. Society’s growth in new construction is a big part of this, and by planning and building more sustainable buildings these requirements can be fulfilled. The development of flexible buildings, which can adapt to future needs of society, lead to a more efficient utilization and longevity of premises and generate more sustainable buildings.In Sweden, the municipalities are the country’s largest property developers and therefore have a significant responsibility to provide society with real estate and public buildings. In recent time we have seen a shift towards flexible public buildings and in particular preschools. With the current socio-economic climate and ageing population buildings like preschools need to be flexible to ensure they can cater for future demands of society.

    This degree project, within the Bachelor programme in Construction Engineering, has been carried out during 10 weeks on Tengbom Architects in Uppsala. The thesis deals with the subject of flexibility in buildings and includes a proposal for the design of a flexible building as a pre-school that in the future can be converted into a retirement home.

  • 2.
    Abrahamsson, Niklas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Individuell mätning och debitering av värme i flerbostadshus: Svenska förutsättningar i jämförelse med erfarenheter från Tyskland och Danmark2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today it is unusual to use consumption based billing of heat in Swedish apartment buildings. This is more common in the rest of Europe and this study aims to learn about experiences and possible problems from Germany and Denmark, which are countries who have this system implemented in their law. The current study is made on behalf of the Swedish Union of Tenants, the Swedish Association of Public Housing Companies (SABO) and the Swedish Property Federation as part of a project where these organizations want to establish a recommendation for their members if they would like to start using the method.

    Differences within countries that are examined include climate, the property´s energy performance, local habits, rent-setting system, business model for energy sales and the law. The techniques to measure consumption are also described. The main objective of this report is to increase understanding and knowledge in this subject. The report is meant to serve as a basis for a recommendation on introducing this system in Sweden.

    As can be seen from the comparison, Sweden in many cases has similar conditions as Germany and Denmark. There are also substantial differences. For example it may be difficult to transfer heating costs separately from the basic rent because of the Swedish rent-setting system. Due to the colder climate in Sweden, the energy savings would be greater in absolute terms. It can also be seen that German and Danish laws regulates the market in a similar way. If implemented in Sweden in its current form, the European Energy Directive could force legislation for the mandatory introduction of the system.

  • 3.
    Adolfsson, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Simplified finite element bearing modeling: with NX Nastran2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report was produced at the request of ABB Robotics and the work was conducted at their facilities in Västerås, Sweden.

    In the development of industrial robots the structures are slimmed to increase the accuracy and speed. When conducting finite element analysis on the robots the accuracy of the component modelling and definitions of the boundary conditions becomes more important. One such component is the ball bearing which consist of several parts and has a nonlinear behavior where the balls are in contact with the rings.

    The task given was to develop new methods to model roller bearings in Siemens finite element modelling software NX Nastran. Then conduct a strain measurement, to compare the methods to real experimental values. The goal with the report is to find one or more methods to model roller bearings, with accurate results, that can beused in their development work.

    The report was conducted by first doing a study on bearings and finite element modeling, and learning to use the software NX Nastran. Then the development of the methods were done by generating ideas for bearing models and testing them on simple structures. Nine methods was produced and a tenth, the method used to model bearings today, was used as a reference. The methods was used to build bearing models in a finite element model of a six axis robot wrist.

    Simulations were done on the models with different load cases and the results were compared to a strain measurement of the wrists real counterpart. Only six of the models were analyzed in the result, since four of the models returned results that were deemed unusable.

    When compiling the result data no model was found to accurately recreate the stresses in every load case. Three methods, that allow deformation, performed similarly. One of them is suggested to be used as modelling method in the future. Worst of the methods, according to the results compiled, was found to be the method used today. It fails to describe local stresses around the bearing. For continued work it is suggested that linear contact elements is studied further. Four out of five models constructed with linear contact elements failed to return satisfactory results.

  • 4.
    Afshar, R
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    van Dijk, N.P.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Bjurhager, Ingela
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Gamstedt, E. Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Comparison of experimental testing and finite element modelling of a replica of a section of the Vasa warship to identify the behaviour of structural joints2017In: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 147, p. 62-76Article in journal (Refereed)
    Abstract [en]

    Modelling in design of new support systems necessitates the joint stiffness of the existing wooden structures. In valuable structures, e.g. in cultural heritage, or structures with inaccessible joints, these stiffness values must be estimated, e.g. by testing joints in tailored replicas of the original parts. Although a simplified structure, the replica, can call for finite element (FE) modelling to capture the stiffness parameters. The first step in such a process is to compare FE predictions with experimental tests, for validation purposes. The reasons for unavoidable differences in load-displacement behaviour between model predictions and experimental test should be identified, and then possibly remedied by an improved model. Underlying causes like the complex shape of joints, geometrical uncertainties, contact mechanisms and material nonlinearity are generally too computationally expensive to be included in a full-scale model. It is therefore convenient to collect such effects in the contact penalty stiffness in the joint contact areas where stresses are high, which influences the resulting joint stiffness. A procedure for this is here illustrated for the case of the 17th century Vasa shipwreck A replica of a section of the ship has been constructed, and its joints were tested in bending-compression, in-plane shear and rotation. The FE simulations showed stiffer behaviour than the experimental results. Therefore, a normal penalty stiffness in contact surfaces of the joint were introduced, and used as a calibration parameter to account for the simplifying assumptions or indeliberate imprecision in the model, e.g. concerning boundary conditions, material properties and geometrical detail. The difference between numerical predictions and experimental results could then be significantly reduced, with a suitable normal penalty stiffness value. Once an acceptable finite element model has been obtained, it is shown how this can be used to identify stiffness values for joints in the physical structure with compensation for degradation of material properties due to aging and conservation treatment.

  • 5.
    Afshar, Reza
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Alavyoon, Navid
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Ahlgren, Anders
    Swedish National Maritime Museums, the Vasa Museum.
    van Dijk, Nico P.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Vorobyev, Alexey
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Gamstedt, Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    A full-scale finite-element model of the Vasa ship2017In: Proceedings of ECCOMAS Thematic Conference CompWood 2017: Computational Methods in Wood Mechanics, 2017Conference paper (Refereed)
    Abstract [en]

    A full-scale model of the 17th century Vasa shipwreck has been developed to assess its current and future structural stability as well as design an improved support structure. A wireframe model, consisting of only lines, points and curves to describe the geometry of the ship, has been provided by the Vasa museum. It has been developed based on geodetic measurements using a total station. From this wireframe model, a three-dimensional (3D) model comprising solid bodies for solid-like parts (i.e. hull and keel), surfaces for the shell-like components (deck planks) and lines for beam-like constituents (deck beams) has been developed in Creo Parametric 3D software. This geometric model has been imported in finite-element software, Ansys, for further development of the stiffeners (knees, riders, stanchions, masts, etc.), adjustment of the correct location of deck beams and, finally, structural analyses of the entire ship (Figure 1). The procedure for selection of the different types of elements in the finite-element (FE) model, the definition of orthotropic material properties for the timber structure and preliminary results are discussed in this paper. Experiences drawn from this engineering project may also be useful in development of finite element models for structural assessment of other complex wooden structures in cultural heritage.

  • 6.
    Ahlstedt, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Bygglogistik i en regionstad: Köra hit eller köra bort?2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The work is being carried out with the construction company Arcona.The aims are to evaluate and make recommendations about theirbuilding logistics solution CSL. For now, CSL is only used forprojects in Stockholm. If a need for CSL occurs in Uppsala, it willalso be introduced there.The purpose of the study is to investigate how CSL works inStockholm, what good experiences and challenges identified by theusers in Stockholm. Another purpose is to identify which partfunctions of the logistics solution that are requested by futureusers in Uppsala.To find out how the solution works today on projects in Stockholm,three qualitative interviews have been conducted. To find out aboutthe expectations of subcontractors (UE) on a logistics solution inUppsala, a qualitative interview has been conducted with asubcontractor. All interviews were then encoded to find themes andsubcategories.The conclusion is that both the subcontractor and Arcona see bothpractical and financial gains in introducing CSL in Uppsala. The mainadvantage of CSL is that it is scalable and you can choose to insertonly the sub-functions that are needed on the current project. Aservice that both sees benefits and which can be recommended is alogistics coordinator who reviews the entire logistics at theworkplace and thereby more easily identifies and solves problems.

  • 7.
    Albrecht, Felix
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Numerical modeling and simulation of the deformation of wood under an applied indentation load2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 8.
    Alcazar, William
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Hammargren, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Anläggning av traditionellt VA-schakt: En fallstudie i logistik och byggstyrning2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A growing issue in the construction industry is how production can become more

    efficient by using logistical solutions. Companies can minimize the cost of a project by

    reducing the time to perform the work.

    The purpose of this report was to examine the logistics related to pipe trenches for

    SIAAB. The report's focus has been on solving problems and planning that would

    facilitate the work of the project Vaksala-Lunda Etapp 3.

    The case study consists of interviews with SIAAB's employees and an observation

    where the progress of a traditional pipe trench has been documented using checklists.

    Questions to the report’s case study come from the theoretical part, which is based

    on literature on construction management and logistics in general. The observation

    lasted five weeks and the biggest time-consuming events that affected the pipe trench

    during this time, has received most attention. Last part of the report is a compilation

    of the authors' own thoughts and opinions.

    The production was difficult in this case because the earlier stages of the project were

    weak. The extent of SIAAB's planning could have been higher, but this was

    complicated when employees were tied to previous projects.

  • 9.
    Almkvist, Gunnar
    et al.
    Swedish Univ Agr Sci SLU, Dept Chem & Biotechnol, Box 7015, SE-75007 Uppsala, Sweden..
    Norbakhsh, Shahin
    Swedish Univ Agr Sci SLU, Dept Chem & Biotechnol, Box 7015, SE-75007 Uppsala, Sweden..
    Bjurhager, Ingela
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Varmuza, Kurt
    Vienna Univ Technol, Inst Stat & Math Methods Econ, Wiedner Hauptstr 8-10-E105, A-1040 Vienna, Austria..
    Prediction of tensile strength in iron-contaminated archaeological wood by FT-IR spectroscopy - a study of degradation in recent oak and Vasa oak2016In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 70, no 9, p. 855-865Article in journal (Refereed)
    Abstract [en]

    Oak from the Swedish warship Vasa and recent oak that was aged after impregnation with iron(II) chloride has been analyzed by FT-IR spectroscopy and submitted to tensile strength testing. The aim was to investigate correlations between FT-IR bands in the fingerprint region, chemical degradation, and tensile strength in iron contaminated oak. The concentration of carboxylic functions increased and the acetyl groups in the hemicellulose fraction were decreasing as a function of degradation time. These changes are accompanied by reduced tensile strength and elevated content of oxalic acid (OA) in both Vasa wood and the impregnated recent oak samples. To evaluate the possibility to predict tensile strength from spectral data, chemometric modeling by partial least-squares (PLS) regression was applied. The strategy of repeated double cross validation (rdCV) allowed a realistic prediction of tensile strength. Overall, chemical changes and mechanical performances of iron contaminated wood are strongly correlated and thus FT-IR spectroscopy is suited to predict the strength properties of the degraded wood.

  • 10.
    Amanda, Holmkvist
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Inverkan av torktemperatur vid vattenmättning av bruk och betong: Bestämmning av vattenmättnadsgrad och hydraulisk konduktivitet2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, there is uncertainty about how much the results differ when drying concrete

    at 20, 50 and 105 °C prior to saturation of concrete in order to determine the

    degree of saturation and hydraulic conductivity. Micro-cracks occur when concrete is

    dried at higher temperatures and causes increased hydraulic conductivity. Further, the

    concrete is believed not to be completely saturated if not all the physically bound

    water, so called free water, has been dried out prior to saturation.

    This thesis compares the effect of three different drying temperatures on the

    possibility to saturate concrete with water. The work was conducted at Vattenfall’s

    concrete laboratory in Älvkarleby. The three drying temperatures were +20 °C

    (room temperature), 50 °C and +105 °C. The objective was to determine if

    differences on the degree of saturation and hydraulic conductivity were non-existent

    or negligible. Vacuum saturation after drying at 105 °C is considered to be complete.

    The results after drying at 20 °C and 50 °C were compared to those after drying at

    105 °C. The results of the tests indicate that the concrete should be dried at +105°C

    prior to saturation with water. Then the risk of frost damage to concrete in hydro

    power structures can be assessed.

    How determination of the hydraulic conductivity is affected by the drying

    temperature gave more vague and dubious results. All specimens showed a maximum

    hydraulic conductivity after drying at 50 °C, not after 105 °C as expected. It was

    believed that the hydraulic conductivity theoretically would increase because of

    (more) micro-cracks when being dried at 105 °C. Results from the concrete with vct

    1.0 gave results that indicated that the specimens had been damaged by method 1. To

    sum up, the results of the tests indicate that further studies on the effects of drying

    temperatures should be made.

  • 11.
    Andersson, Frida
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Stabilitet och tillåten rörelse hos flervåningsbyggnader: Analys av höga byggnaders begränsningar till dynamiska krafter och svängningar2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    One of the challenging design areas of high buildings is the determination of its stability and response to dynamic forces. These factors affect the horizontal deformations and fluctuations that the building will result in. This report examines the demands placed on the stability and deformations of high buildings through a literature study as well as examines these requirements with a reference building built into FEM-Design. The literature study shows that quite a few standards have to be taken into account and used in the design of tall buildings. Regarding limit values, only SS-ISO 10137 specifies maximum values for a building's peak acceleration relative to its own frequency. Limit values for transient deformations are not available. Furthermore, the literature study shows that plenty of studies of human perception and tolerance to movements in buildings have been performed. The movements have been shown to cause physical andmental discomfort if exaggerated, which SS-ISO 10137 bases its limits after. The 75-meter reference building, modeled in FEM-Design, was built to calculate the building's own frequency, transient deflection, and self-weight. The wind loads have been calculated separately and entered into the program. Calculations for the building's peakacceleration have then been calculated and compared to the limitvalues in SS-ISO 10137. The structure of the reference building, consisting of 25-storeys in concrete, met the standard requirements for housing and should be able to be built without the risk of discomfort among the residents. Other inputs were 250 and 200 mm floor and wallthickness in C25 / 30 and VKR pillar in each corner, 200x200x10 mmin quality S355. The plan levels are square 21.8m wide andidentical to all 25 levels.The model-building met the requirements for living space accordingto SS-ISO 10137 with respect to peak acceleration and frequency. However, the calculated horizontal deformations did not have anylimit values to be compared to and were therefore not compared to any restrictions.

  • 12.
    Andersson, Pelle
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Effektivisering av materialleveranser: En undersökning av möjliga förbättringar för leveranser av våtrumsinredning på JM2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Logistics in the construction industry is a difficult and troubled area with great room for improvement. Planning, preparation, management and control over material flow have become increasingly important for a company in order to keep up with the competition and reduce their costs.

    The purpose of this thesis is to investigate and identify possible improvements in the supply management regarding the interior for the sanitary rooms at JM- constructions. To identify possible issues with the supply management three of JMs projects in Uppsala have been analyzed.

    The result presented in this report shows that there is problems with the current supply management, problems which can be solved by introducing a Construction Consolidation Centre.

    Furthermore recommendations are given to introduce a pilot project with a Construction Consolidation Centre including: washstand, mirror cabinet, shower screen and towel rack. 

  • 13.
    Andreasson, Josefine
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Falck, Sandra
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    När befintligt ska bli nytt: Optimering av ombyggnation i befintlig kontorslokal2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Vid utformning av kontor är krav på arbetsmiljö, tillgänglighet, trivselfaktor och att kunna påvisa sitt varumärke i kontoret av vikt. För att kontoret ska bidra till ett positivt arbetsklimat och ett effektivt arbetssätt bör även utformningen anpassas till den specifika verksamhet som bedrivs. Ett kontor med attraktiv utformning och bra arbetsmiljö ökar organisationens attraktionskraft mot befintliga och framtida medarbetare.

    Rapporten behandlar krav och aspekter att beakta vid ombyggnation av kontor och planering av ny kontorstyp i existerande lokaler. Med ett befintligt kontor finns givna förhållanden som ska tas hänsyn till och därför sammanfattas fakta om tekniska- och social aspekter som är av vikt vid valet av kontorstyp. Tekniska aspekter är ljud, ljus, luft, temperatur, bärande byggnadsdelar, vatten och avlopp, brand och el. Sociala aspekter innefattar ergonomi, kulörval, medarbetarhälsa, digitalisering, estetik och inredning. Olika kontorstyper beskrivs och utformningskrav från lagar och branschföreskrifter presenteras.

    Utförd studie baseras på en fallstudie av Skanskas kontor i Uppsala där en behovsanalys utförs och ett förslag på aktivitetsbaserad kontorslösning presenteras. 

  • 14.
    Antell, Malin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    En jämförelse mellan uppmätt och framräknad A-temp2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The main purpose of this paper was to compare the measured A-temp with the calculated A-temp. A–temp is an area term used in Sweden when calculating the buildings energy usage while performing energy assessments.To obtain A-temp you can measure it, this way you will get the exact value. Or you can calculate it, from other already existing area measurements. It is easier and more time efficient to calculate A-temp but it may deviate from the real A-temp.What I found in my study was that for most of the buildings I had chosen, there was not a very big deviation, between measured and calculated A-temp. The largest difference was when calculating A-temp from BOA+LOA when in two of the cases there were differences of 15 %.When doing this study, I have measured A-temp for the buildings, on blueprints. I have calculated A-temp from already measured area and compared them to each other.

  • 15. Appelgren, Patrik
    et al.
    Skoglund, Melker
    Lundberg, Patrik
    Westerling, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Hurtig, Tomas
    Experimental Study of Electromagnetic Effects on Solid Copper Jets2010In: Journal of applied mechanics, ISSN 0021-8936, E-ISSN 1528-9036, Vol. 77, no 1, p. 011010-Article in journal (Refereed)
    Abstract [en]

    In this paper we present a study of the interaction between all electric current pulse and a solid copper jet. Experiments were performed using a dedicated pulsed power supply delivering a current pulse of such amplitude, rise little, and duration that the jet is efficiently affected. The copper jet was created by using a shaped charge warhead. All electrode configuration consisting of two aluminum plates with a separation distance of 150 mm was used. The discharge current pulse and the voltages at the capacitors and at the electrodes were measured to obtain data oil energy deposition in and the resistance of the jet and electrode contact region. X-ray diagnostics were used to radiograph the jet, and by analyzing the radiograph, the degree of disruption of the electrified jet could be obtained. It was found that a current pulse with an amplitude of 200-250 kA and a rise time of 16 mu s could strongly enhance the natural fragmentation of the jet. In this case, the initial electric energy was 100 kJ and about 90% of the electric energy was deposited in the jet and electrodes. At the exit of the electrode region, the jet fragments formed rings with a radial velocity of up to 200 m/s, depending oil the initial electric energy in the pulsed power supply. [DOI: 10.1115/1.3172251]

  • 16.
    Arnsten, Emma
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Öhman, Ellen
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Användbarheten av Tekla i Betongkonstruktioner: En jämförelsestudie mellan två modelleringsprogram2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has examined the Tekla Structures modeling software and answered the question of whether it could act as a suitable modeling program for the design department at Bjerking AB in Uppsala. The method used in this work is a case study of a previous project with existing basis to work form. The demarcation of the study was to examine only the usability of the foundations of in situ concrete. 

    The work examined three main areas within the design process. The first was to model the concrete elements then to model the reinforcing and ultimately production of the drawings. Because Autodesk Revit was the existing modeling program in the Department conducted the evaluation as a comparison between the two programs. The condition was that all three main parts would be made in the same program. 

    The results showed that Tekla Structures has great potential in the field of concrete modeling, and that it is a suitable modeling program to use for projects thats include foundations in situ concrete. The study has also shown the programs benefits to model reinforcement in 3D in these types of projects. 

  • 17.
    Ascione, Luigi
    et al.
    UNISA, Italy.
    Caron, Jean-François
    ENPC, France.
    Godonou, Patrice
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    van Ijselmuijden, Kees
    RHDHV, the Netherlands.
    Knippers, Jan
    ITKE, Germany.
    Mottram, Toby
    Warwick AC, UK.
    Oppe, Matthias
    KHING, Germany.
    Gantriis Sorensen, Morten
    Fiberline, Denmark.
    Taby, Jon
    FIRECO, Norway.
    Tromp, Liesbeth
    RHDHV, the Netherlands.
    Prospect for new guidance in the design of FRP: Support to the implementation, harmonization and further development of the Eurocodes2016Report (Refereed)
    Abstract [en]

    Over the last twenty years, many innovative solutions have confirmed the usefulness of composite structures realized with FRPs (Fibre Reinforced Polymer or Plastic). The need of European standards for use of fibre reinforced polymer composites in civil engineering was justified in 2007 in the JRC Report EUR 22864 EN. The new European technical rules will be developed using the existing organization of CEN/TC250.The present report has been worked out in the frame of CEN/TC250/WG4 activities. The report encompasses:

    • Part I, which introduces the policy framework and the CEN/TC250 initiative
    • Part II, which gives a prospect for CEN guidance for the design and verification of composite structuresrealized with FRPs

    The report presents scientific and technical background intended to stimulate debate and serves as a basis for further work to achieve a harmonized European view on the design and verification of such structures. This has been the main impulse to include the work item of the Fibre Reinforced Polymer Structures in the Mandate M/515 with high priority.

  • 18. Aslund, Par E.
    et al.
    Hagglund, Rickard
    Carlsson, Leif A.
    Isaksson, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Modeling of global and local buckling of corrugated board panels loaded in edge-to-edge compression2014In: Journal of Sandwich Structures and Materials, ISSN 1099-6362, E-ISSN 1530-7972, Vol. 16, no 3, p. 272-292Article in journal (Refereed)
    Abstract [en]

    Detailed structural nonlinear finite element modeling of a sandwich panel with corrugated core is performed in this study. A simply supported panel is loaded in uniaxial compression well into the regimes of global panel buckling and local face sheet buckling. The highly nonlinear load versus in-plane and out-of-plane displacement responses obtained from finite element analysis agree reasonably well with experimental results, but the model slightly overpredicts the maximum load. The difference between experiments and predictions is attributed to damage of the corrugated paper web introduced during manufacture of the core and corrugated board. Computations of the buckling also results in a slight thickness reduction of the panel for a large range of face and web thicknesses identify lower thickness limits when the web loses its ability to contribute to the compressive strength of the panel. The highly nonlinear response associated with local and global buckling also results in thickness reduction of the panel.

  • 19.
    Axelsson, Cecilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Leveransproblem: Ett problem vid strukturerad produktion2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When building large buildings, such as compartment buildings, there is a number of deliveries arriving on the construction site daily. In order to receive these deliveries without disturbing the rest of the work going on JM often books a fixed unloading time. When doing that they can be prepared when the delivery arrives. Making sure there is a suitable unloading area, someone to meet the delivery and when needed proper machines, such as a tractor or a crane, to help unload bigger deliveries. The person receiving the delivery is supposed to make an acceptance control where they check the delivered goods making sure nothing has been damaged in transport and that they have received what they were supposed to receive. Also noting whether the delivery arrived on time or not.

     

    In 2010 JM introduced structured production as their take on lean, and thus working more effectively. Structured production at JM means that everyone in the company performs the same task in the same way according to a predetermined assembly instruction. It also includes a certain way to make time plans for the whole project as well as for the next 5 weeks. As for deliveries JM tries to order these as close to just in time as possible. That reduces keeping material in stock at the construction site and also handling this material more than necessary. Handling material in stock is a big source of accidents and takes time away from other work. However, it is very vulnerable to have essential supplies arrive to the construction site just when they are needed as a delay can ruin the whole timeline of the production.

     

    This report aims, through qualitative studies, to find out how widespread the problem of late deliveries is at JM'S three construction sites in Uppsala and what JM is able to do to avoid it.

     

    The study showed that if deliveries are delayed, it refers almost exclusively to 1-5h on the desired delivery date. Deliveries being delayed so that they do not arrive on the right day were very unusual. One of the questions in the interviews was also whether JM themselves could have a negative effect on deliveries arriving on time by making changes in their orders, but this seems to have no significance when changes are made only after approval by the supplier and that the vast majority of deliveries after all still arrives on the right day. It rather seems that some providers take the order of a fixed unloading time less seriously.

    Something that does not make things better is that the procedure for handling delayed deliveries varies a lot just between the three construction sites in Uppsala and also between supervisors on the same construction site. It is not even always the case that the supplier is notified that the delivery was late, and then they do not know that they need to improve. Most suppliers buy in the transport of a shipping company and order a fixed unloading time from them. The suppliers interviewed all said that they wanted to know if the delivery was late so that they can contact the shipping company.

  • 20.
    Backåker, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Harder, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Utvecklingsanalys av installationssystems montering vid industriellt träbyggande: Värme, vatten, ventilation, el och avlopp2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The industrialized timber housing process is capable nowadays to build multi-storeyhouses since fairly new changes in the Swedish regulations where made after theadmission of the European Union in 1994.The industrialized process moves parts of the construction process into a highlyeffective factory where 3D-volumes of the building are prefabricated beforetransportation to the building site for assemble.The assembly process is relatively effective compared to the completion of thebuilding service system and this is therefore the main focus in this thesis. This thesisattends problems with completion of the building service system, and thereforedemarcates from other aspects, such as technical and economic aspects, of thebuilding service system.The degree of completion of the flats differs from completion of the connectivepassages, for example hallways, in a way that suggests a need for further investigation.This thesis includes analysis of the possibilities to increase the prefabricatedconnective passages, to the extent of containing building service systems.An increase of the prefabrication of the building service system has a greatdevelopment potential, even though some restraining factors need to be solvedbefore implementation.This thesis was made in collaboration with two of Sweden’s leading companies on themarket of multi-storey industrialized timber housing, Moelven ByggModul AB andLindbäcks Bygg AB.

  • 21.
    Bashir, Hussam
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Calculation of Wave Propagation for Statistical Energy Analysis Models2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis investigates the problems of applying Statistical Energy Analysis (SEA) tomodels that include solid volumes. Three wave types (Rayleigh waves, Pressure wavesand Shear waves) are important to SEA and the mathematics behind them is explainedhere. The transmission coefficients between the wave types are needed for energytransfer in SEA analysis and different approaches to solving the properties of wavepropagation on a solid volume are discussed. For one of the propagation problems, asolution, found in Momoi [6] is discussed, while the other problem remains unsolveddue to the analytical difficulties involved.

  • 22.
    Batti, Aryan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Hedlund, Jakob
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Byggarbetsmiljösamordning: En analys av hur byggarbetsmiljösamordning sker idag och hur den kan förbättras2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to analyse the current state in the construction sectorwithin the co-ordination of building work environment. The outcome of the analysiswill be implemented in a process model which aims to secure a safe workenvironment. As a result of a change in the Swedish Work Environment Act in 2009the government presented two new titles in the construction sector. The two newtitles were named: building work environment coordinator for design and planning (BAS-P) and building work environment coordinator for execution(BAS-U).Together they are responsible for the building work environmentco-ordination throughout the whole building process.

    The information gathering for the study was mainly based on interviews carried outwith professionals with experience from either of the two titles. Although the workprocess is regulated by the law but also internally in the companies, there is still awide diversity in how the work is executed. The interviews also led to the conclusionthat there is a lack of communication between the two parts and further thatsome designers are lacking in knowledge of how the designed details are carriedout in practice.

    After the conclusions above were made, a process model which will encourage active communication was developed. The process model is a folder hierarchy which will simplify the co-ordination of building work environment for each operator. It is also a way for the companies of ensuring that each operator uses the samedocuments in order to set a standard and prevent miscommunication.

  • 23.
    Berefelt, Erik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Olsson, Linn
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Utvärdering av olika metoder för fuktstyrning i kyrkor2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis examines three medieval churches within Lagunda parish in Örsundsbro.The parish has previously had problems with mould growth and has therefore, inselected churches installed various types of moisture control, together with devicesfor measuring temperature, relative humidity and mixing ratio, at three locations inthe churches. The moisture control should in an energy efficient way reduce the riskof mould growth and thus reduce the future maintenance costs.

    The purpose of this thesis is to analyse the results and to see how the moisturecontrol measures has worked in the churches. The data has been collected in theprogram Omnisens and compiled by Magnus Wessberg at Uppsala University, whichresulted in diagrams that include relative humidity and mould risk, which theanalysis has been based on. Two different moisture control measures have beenused in the churches that this thesis examines. The measures are condensationdehumidifier and moisture controlled ventilation.

    The result is varying between the churches but shows that there has been a needfor moisture control that reduces the relative humidity indoors. The energy usagehas differed between the measures, but should not be crucial when deciding onfuture measures.The result also shows that the indoor climate is largely influencedby rainfall and that the church's organs in the study should be taken into account infuture measure, since the result when there is a risk of mould differs from otherparts of the churches.

  • 24.
    Berggren, Jonathan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Miljöbyggnad, GULD värt?: En undersökning av fastighetsägares erfarenheter och tankar kring ett nytt certifieringssystem2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    During the past few years an increased attention has been paid to environmental issues in the construction and property sector in Sweden. In order to simplify the work with these issues a Swedish environmental certification system for buildings called Miljöbyggnad has been developed. This thesis aims to investigate the opinion of a selected number of selected property owners of Miljöbyggnad. From that basis recommendations and actions for the future work with the system will be presented.

    The investigation has been conducted through personal interviews with five property owners. The main issues that the interviews have been based on are their purpose, experiences, perceived complications and future prospects in terms of certification using Miljöbyggnad.

    The system intends to be cost-effective, simple and to offer a relevant environmental assessment of buildings and the result from the report indicates that this is largely fulfilled. All respondents believe that Miljöbyggnad offers a relevant environmental assessment. All of them also believe that the system is simple except for some complications and 80 % believe that the system is cost-effective. In terms of the future, all interviewed property owners will most likely certify buildings under Miljöbyggnad, some to a greater extent than others.

    The conclusion from this investigation is that the system needs to be dynamic. Adaption to the social, environmental, technical, economical and legal conditions that prevail is vital. However, it is recommended that Miljöbyggnad retains its simplicity and avoid growing to become too comprehensive.

  • 25.
    Berglund, Gabriella
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Utveckling av fastighet i Uppsala innerstad: Förslagshandlingar till flerbostadshus för studenter2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 26.
    Bergman, Adam
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Tidsslöseri i byggbranschen: Synliggörande av problem med tidsslöeri i byggproduktion2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to give a clear indication of how widely spread the

    problem with time waste is in the construction industry. One of the big issues of

    today is the large increase in construction cost of residential buildings. The cost of

    producing new apartment buildings has increased with 140 percent in less than 20

    years. Furthermore the study show that only 17.5 percent of a construction workers

    day is value increasing work. The same study also show that 37.5 percent of a work

    day is waste that can be completely eliminated and has no value to the customer. A

    good way to approach this time waste problem could be to implement LEAN in to

    the construction industry. This report is done together with Skanska Sweden AB in

    Uppsala. The main research methods used in this report is a literature study,

    interviews, an inquiry and visits to the construction sites. The result presented in this

    report shows that there is a problem with time waste in Skanska projects in a couple

    of different areas. The conclusions to this report show that the knowledge about

    LEAN today is poor, negative attitude towards changes, these arguments are

    hindering work to improve Production efficiency in the construction companies.

    LEAN education for employees and dividing responsibility to all the workers on site

    could be solutions that could change the industry to a more cost efficient

    construction process.

  • 27.
    Berto, F.
    et al.
    Norwegian Univ Sci & Technol NTNU, Dept Engn Design & Mat, Trondheim, Norway..
    Afshar, Reza H.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Inclined Hole Under Different Loading Conditions: A Review of Recent Results2016In: Strength of Materials, ISSN 0039-2316, E-ISSN 1573-9325, Vol. 48, no 5, p. 668-676Article, review/survey (Refereed)
    Abstract [en]

    Three-dimensional (3D) elastic stress distributions in the vicinity of the sharp corners of an inclined diamond hole in a plate are investigated. A detailed 3D finite element model under different loading conditions is analyzed to study the intensity of different fracture modes due to the thickness effect. The stress results are compared with those provided by a recent theory which reduces the 3D governing equations of elasticity to a differential equation system, which includes a biharmonic equation and a harmonic equation. They provide the solution of the corresponding in-plane and out-of-plane notch problem, respectively, and have to be concurrently satisfied. Comparing numerical results and theoretical stress distributions, a good agreement is found.

  • 28.
    Bertze, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Från BIM-modell till logistik: Möjligheten att digitalisera materialflödet2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When all the information for smart building materials orders can be extract from aBIM model it is possible for correct material to be delivered at the right time at theright place. If a flow of material is well planned it leads to a more efficient work on theconstruction site and reduced waste.Overall, the relationship between material supplier and contractor has receivedsurprisingly little attention in research. Especially considering the amount ofcontractor-supplier-relationship there is in each building project. In this bachelorthesis the possibility of using information from a BIM model to a digital material orderis investigated. Furthermore, the need and problems in the digitizing process of thematerial flow and its operators is studied. The results show that a digitalcommunication is possible but requiring a major change in the process of materialflow.

  • 29.
    Bjurhager, Ingela
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Gamstedt, E. KristoferUppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Predicting creep rate in archeological wood from theVasa ship – a first appraoch2012Conference proceedings (editor) (Refereed)
  • 30.
    Bjurhager, Ingela
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Gamstedt, Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Keunecke, Daniel
    Niemz, Peter
    Berglund, Lars A.
    Mechanical performance of yew (Taxus baccata L.) from a longbow perspective2013In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 67, no 7, p. 763-770Article in journal (Refereed)
    Abstract [en]

    Yew (Taxus baccata L.) longbow was the preferred weapon in the Middle Ages until the emergence of guns. In this study, the tensile, compression, and bending properties of yew were investigated. The advantage of yew over the other species in the study was also confirmed by a simple beam model. The superior toughness of yew has the effect that a yew longbow has a higher range compared with bows made from other species. Unexpectedly, the mechanical performance of a bow made from yew is influenced by the juvenile-to-mature wood ratio rather than by the heartwood-to-sapwood ratio. A yew bow is predicted to have maximized performance at a juvenile wood content of 30-50%, and located at the concave side (the compressive side facing the bowyer). Here, the stiffness and yield stress in compression should be as high as possible.

  • 31.
    Bjurhager, Ingela
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Halonen, Helena
    Wallenberg Wood Science Center, KTH, Stockholm.
    Lindfors, Eva-Lisa
    Innventia AB, Stockholm.
    Iversen, Tommy
    Wallenberg Wood Science Center, KTH, Stockholm.
    Almkvist, Gunnar
    Dept of Chemistry, SLU, Uppsala.
    Gamstedt, E. Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Berglund, Lars A.
    Wallenberg Wood Science Center, KTH, Stockholm.
    State of Degradation in Archeological Oak from the 17th Century Vasa Ship: Substantial Strength Loss Correlates with Reduction in (Holo)Cellulose Molecular Weight2012In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 13, no 8, p. 2521-2527Article in journal (Refereed)
    Abstract [en]

    In 1628, the Swedish warship Vasa capsized on her maiden voyage and sank in the Stockholm harbor. The ship was recovered in 1961 and, after polyethylene glycol (PEG) impregnation, it was displayed in the Vasa museum. Chemical investigations of the Vasa were undertaken in 2000, and extensive holocellulose degradation was reported at numerous locations in the hull. We have now studied the longitudinal tensile strength of Vasa oak as a function of distance from the surface. The PEG-content, wood density, and cellulose microfibril angle were determined. The molar mass distribution of holocellulose was determined as well as the acid and iron content. A good correlation was found between the tensile strength of the Vasa oak and the average molecular weight of the holocellulose, where the load bearing cellulose microfibril is the critical constituent The mean, tensile strength is reduced by approximately 40%, and the most affected areas show a reduction of up to 80%. A methodology is,, developed where variations in density, cellulose microfibril angle, and PEG content are taken into account, so that. cell wall effects can be evaluated in wood samples with different rate of impregnation and morphologies.

  • 32.
    Bjurhager, Ingela
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Vorobyev, AlexeyUppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.van Dijk, NicoUppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.Gamstedt, E. KristoferUppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.Ahlgren, AndersOlofsson, Magnus
    Investigation of time-dependent deformation of wood from the warship Vasa2013Conference proceedings (editor) (Refereed)
  • 33.
    Blom, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Thored, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    STABILA HÖGHUS I TRÄ: En analys av infästningars inverkan på accelerationer och utböjningar i ett 15-våningshus av trä2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In today’s society cities grow increasingly larger, not only on the ground but vertically as well. Utilizing height means taller buildings, which often are large steel- and concrete constructions. Why not construct tall buildings out of timber instead, a material by many believed to be far better from an environmental perspective than steel and concrete? The answer lies in the lack of knowledge regarding tall timber constructions and the stresses they need to withstand.

    The report was conducted at the construction consulting company Bjerking AB, Uppsala. The focus in this report was to examine accelerations and deformations as an effect of wind loads. The issue at hand was whether the connections between building elements affect the dynamic responses that occur.

    The chosen model was a 15 storey timber building whose walls and floors consisted mainly of cross laminated timber elements as the load bearing structure. As a large amount of the analyses were complex, the calculations were made in the computer program FEM-Design, which is a finite element program.

    After performing numerous calculations with different settings, a result emerged. Clear trends could be seen in the connections’ influence on accelerations and deformations. A stiffer connection makes the building more resistant to wind loads. This result has to be considered when constructing tall timber buildings to avoid problems with accelerations and deformations. However, merely adjusting the connections to meet requirements is not sufficient, other measures are also needed.

  • 34.
    Blomqvist, Erika
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Ledje, Ante
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Hållbar avfallshantering vid nybyggnation: En jämförelse mellan olika avfallssorteringsmetoder2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Idag eftersträvas i allmänhet en hög återvinningsgrad och framför allt reducerade mängder avfall. Detta är något som bör prioriteras inom bygg- och anläggningsbranschen på grund av de stora mängder avfall som byggsektorn genererar. För att minska mängden byggavfall och framför allt den andel som hamnar på deponi behöver insikten i det avfall som faktiskt genereras öka.

    I det här examensarbetet studeras avfallshanteringen på två nybyggnadsprojekt och hanteringens inverkan på miljö och projektens ekonomi. De båda projekten har vidtagit olika åtgärder för att påverka avfallshanteringen och sorteringen av det blandade avfallet. Rapportens syfte är att belysa hur olika metoder för sortering kan påverka byggavfallet och andelen som går till deponi samt hur detta kan medföra ökad insikt. Målet är att försöka urskilja det bästa tillvägagångssättet att hantera byggavfall och utifrån det skapa en referensram som kan användas vid framtida planering av byggprojekt.

    Undersökningen består i huvudsak av komparativa fallstudier där avfallsstatistik på två projekt jämförs före och efter utförd åtgärd. Vid sidan av detta undersöks även följderna av en hypotetisk fullständig sortering. Litteraturstudier, platsbesök och telefonintervjuer utförs med syfte att få bakgrundsfakta och aktuell information som kan relateras till avfallsstatistiken.

    Resultatet visar att en ökad sorteringsgrad och en minskning av det blandade avfallet medför en ökad deponiandel och därmed ökade fraktionskostnader för deponi. Sett till total fraktionskostnad går däremot kostnaden ner vid en ökad sorteringsgrad. När extern part används för sortering ökar totalkostnaden för avfallshanteringen samtidigt som det sker en ansvarsförskjutning. Ökade kostnader måste vidare sättas i relation till ökad insikt och andra miljövinster. Att därför utifrån undersökningen hävda att det finns en optimal lösning för sortering är inte möjligt då det finns för- och nackdelar med samtliga metoder som undersökts. Vad som däremot kan urskiljas är att en sortering så nära källan som möjligt är att föredra då det medför störst kunskap om avfallets fortsatta funktion i kretsloppet. 

  • 35.
    Boréus, Ida
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Andersson, Sanna
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Den offentliga upphandlingens påverkan på entreprenörer: En studie av små och medelstora byggentreprenörer2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Public procurement in Sweden is regulated by the Act on Public Procure­ment (lagen om offentlig upphandling, LOU, in Swedish). The Public procurement in Sweden stands every year approximately for 500 bil­lion Swedish crowns of the taxpayers’ money. It is therefore im­portant that the money is spent in the best possible way. The focus in this study is set on the relationship between the small- and medium sized building entrepreneurs and the government. The study is built on international scientific arti­cles together with Swedish industry articles and the results from our own interview study. A comparison has been made between the three and it has resulted in listing obstacles for SME (small- and medium sizes enter­prises) and how to overcome these obstacles. 

  • 36.
    Brandt, Stina
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    NOLLDEPONI: - Utopi eller realistiskt mål?2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction industry is one of the main operators at the Swedish industrial

    market, which means that the industry also contributes with a large part of Sweden's

    environmental impact. The construction industry accounts for a third of the country's

    total waste. And today a normal project sends about 10 % of waste to landfill, but

    how should a project proceed in order to achieve zero landfill?

    The purpose of this thesis is to highlight the opportunities that exist in waste

    management in the construction of new buildings and how to prevent landfill. The

    goal is to summarize the results in a checklist to serve future projects.

    The study consists of a literature review in order to determine the current state of

    knowledge in landfill. Interviews with leading persons at two of Skanska's successful

    reference projects were held in order to capture their opinions and thoughts on zero

    landfill, and the factors that made their projects succesful. Interviews were also held

    with waste contractors from two of Sweden's major waste companies, in order to get

    a different angle on the landfill issue.

    The result shows that the issue of zero landfill is very complex and there are many

    factors involved. There is much to improve, but those interviewed believe it is

    possible to achieve zero landfill, through:

    • Commitment in leadership

    • Careful selection of materials

    • Engage waste contractor early

    The question remains whether zero landfill is what benefits the environment most or

    not.

  • 37.
    Brobert, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Leo, Waern
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Ett nytt LEED: Ett verktyg för effektivare hantering av poängen Sourcing of Raw Materials i LEED version 42017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Certification of buildings is now a big part of the construction industry. The role and

    importance of certifications is now undeniable. It has a positive impact on the

    environment, and in the meantime companies can label themselves as eco-friendly.

    Skanska is one of the biggest construction companies in Sweden. Lately LEED has

    become the most common certification system they use on larger commercial

    buildings.

    A new version has just been released, but how well has the system adapted to a

    Swedish market and environment, or vice versa? This can be difficult given that the

    certification system has been developed for an American market. In combination

    with the eventual problems given the system’s origin, working with LEED on the

    construction site is also a lot of work. Our Research indicates that approximately

    20% of a project engineer’s time is taken up by work with the system. This thesis

    examines the possibilities of reducing the amount of time LEED takes up.

    U.S Green Building Council has released a fourth version of LEED. In order to

    streamline the work with certification, an updated tool has been made that explains

    the credit Sourcing of Raw Materials and focuses on the essential parts for people

    who work in construction. In order to do this the previous tool made by Skanska has

    been studied, along with interviews with employees of the company. USGBC’s LEED

    Reference Guide is the core of the information regarding the new version.

    The conclusion is that given the right tools, the work with LEED can be more

    efficient.

  • 38.
    Burman, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Arnberg, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Överlämnandet inom byggarbetsmiljösamordning: Riktlinjer och konsekvenser2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The concept of building work environment co- ordinator is a relatively new concept that has its origin in the amendment to the Working Environment Act which came into force on 1 January 2009. The terms; building work environment co-ordinator appointed for planning and design and building work environment co-ordinator for the execution of building or civil engineering work ushered in the industry. Once these disciplines complement one another, you can achieve a smooth handover to ensure a good and healthy working environment.

    In this thesis, we study a company in Uppsala and their operations and handover by interviewing the relevant staff in question. The result shows that there are currently no present guidelines for how and when the handover should take place, it is up to each individual to provide themselves with the relevant information.

    If the handover of the work environment would occur to the extent it should it would lead to minimized proportions of unforeseen risks and events that may occur during the production phase, which ultimately leads to a better and healthier working environment.

  • 39.
    Bälter, Simon
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Kvick, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Försäkringsbolags kostnader för reparation av fuktskadade badrum2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this report is to compile and examine the cost of renovation of moisture-damaged bathrooms, to derive a target price. The target price can then be used by insurance companies to estimate the ultimate cost of future bathroom renovations.

           The method is based on the compilation and comparison of the cost of repairs of previous water damage in bathrooms. The calculations compiled based on repair estimates for different insurance losses from one of the leading insurance companies in Sweden.

           The result shows the average price per square meter of floor area for different sizes of bathrooms. The average price is the basis for the estimate of future renovation costs of bathrooms. The results further show that the bathroom finishes, area and the distance between the entrepreneur and the location of the renovation have great impact on the final repairing cost. The biggest impact on the final price is the bathroom finishes and area.

     

  • 40.
    Börjesson, Patrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Pantesjö, Marie
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Masshantering av schaktmassor: en jämförelse mellan traditionell masshantering och GPS-styrd masshantering i realtid2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this report is to analyze the advantages of using programme software to monitor masshauling instead of using the conventional method. A comparsion between different programs will also be conducted in an attempt to determine the most affordable. This report is written for NCC Construction AB to help them choose a software most fitting for future projects.The report is based upon literature such as information taken from the developers website, existing reports with similar context, interviews with sellers of the software and interviews with people working in the building sector.The result of this report shows that there are several advantages with investing in a software that helps the management of a project and that it is something that should be taken under consideration instead of the existing method. Topcon is a clear favorite following the inquiries comparisons as done, when they deliver a complete system and not only a supplement to the current approach. Scanlaser are just in the beginning of its development, and is so far only out with an early version of the software, while Topcon has been brought further in development and therefore has more features in the program. To utilize Topcon we fully recommend that the device HT-30 is used.

  • 41.
    Carlstedt, Rikard
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Utvärdering av datorprogram för användning vid dagvattenutredningar2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The main object of this diploma work thesis is about how computer programs can be

    a tool to use for work on stormwater investigations. The advantage of using a

    computer program compared with calculations made by hand is evaluated and

    discussed. The computer programs that have been used for studies and a sequence of

    testing of the possibilities are Autodesks Storm and Sanitary Analysis and DHIs Mike

    Urban.

    Focus on sustainable development now permeates the building industry. As a result

    stormwater investigations have been conducted in an increasing extent the recent

    years. Stormwater is water produced due to precipitation, such as rain and snowmelt.

    Stormwater investigations normally contain descriptions of existing land use, planned

    land use and suggestions of measures and technical solutions for the future disposal of

    stormwater.

    The initial part of the thesis consisted of literature studies on stormwater and

    stormwater investigations to understand the science. Further literature studies

    where related to hydraulic and hydrologic modeling. An analysis of the interest and

    way of applying these methods among municipalities and sewer companies where

    performed. Literature studies and situation analysis formed the basis for the design of

    the evaluation methodology where a number of key points were chosen and

    followed-up for both programs.

    The results of the thesis shows that there is a big advantage in using computer

    simulations for accurate mapping of the pipe networks provided that you also have

    the means to calibrate the hydrologic and hydraulic models. For less accurate

    analyzes, computer programs may be seen as a tool for data management.

  • 42.
    Cedergren, Lucas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Paakkonen, Richard
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    En jämförelse mellan TLS och UAV-fotogrammetri: Inmätning av hårdgjorda ytor2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    At present day there are several different methods for measuring of paved surfaces.

    The most common methods today are measuring with a total station, the Global

    Navigation Satellite System (GNSS) and terrestrial laser scanning (TLS). Recently the

    development of unmanned aerial vehicles, known as drones, has increased

    exponentially and today there are several ways of using drones for measuring surfaces

    by photographing and laser scanning.

    This thesis contains a comparison between the methods terrestrial laser scanning

    (TLS), and unmanned aerial vehicle photogrammetry (UAV). The measurements have

    been applied on two different test surfaces, one of asphalt and one of gravel. The

    purpose of the comparison is to investigate whether the airborne photogrammetry is

    equivalent accurate in its height levels as the terrestrial laser scanning. For the

    comparison to be more extensive, these two methods have not only been compared

    in precision but also in the areas of ease of use and economy.

    The precision was analyzed by comparing the height levels in randomly placed control

    points on the test surfaces. This has been made possible by the creation of terrain

    models of test surfaces in the software Geo where a surface scan of the models have

    been implemented. With the help of surface control the height deviations in the

    control points have been calculated and from these deviations the precision of the

    airborne photogrammetry has been evaluated. The ease of use has been analyzed

    based on observations made and information gathered from experienced consultants

    for each technology. For the economic aspect the costs for each measurement

    method has been presented to get an overall picture of each measurement method

    costs.

    The work has been carried out on behalf of the consulting firm Bjerking AB. The goal

    is to be able to provide Bjerking with a recommendation for which technology is best

    suited for measuring of paved surfaces.

    The results of the survey show that the UAV varies by a mean of 11 mm on the

    surface of gravel and 2 mm on the surface of the asphalt. The final recommendation

    given is that the UAV is preferred for measurement of asphalt roads, because since

    the precision is equivalent to TLS, the method is safe

  • 43.
    Chinga-Carrasco, Gary
    et al.
    Paper and Fibre Research Institute (PFI), Norway.
    Miettinen, Arttu
    Department of Physics, University of Jyväskylä, Finland.
    Luengo Hendriks, Cris L.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Centre for Image Analysis. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction.
    Gamstedt, E. Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Kataja, Markku
    Department of Physics, University of Jyväskylä, Finland.
    Structural Characterisation of Kraft Pulp Fibres and Their Nanofibrillated Materials for Biodegradable Composite Applications2011In: Nanocomposites and Polymers with Analytical Methods / [ed] Cuppoletti, John, InTech , 2011, p. 243-260Chapter in book (Refereed)
  • 44.
    Christine, Zeller
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Kommunikations- besluts- och informationsflöden i byggprocessen2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Construction projects are organized in different shapes and disturbances in the information flow in these processes can lead to problems, such as delays and/or a lower quality. Therefore, a well-functioning interaction between actors and a well thought out-communication at an early stage is of crucial importance. The main question is "How does the communication of decision and information flow in the building process and what barriers and opportunities can be observed?". This diploma work has been written with guidance from Bjerking AB and to answer this question, a collection of empirical data conducted via semi-structured interviews. Respondents with different roles in the construction processes are from the construction companies Bjerking and Ramböll.

     

    Construction projects are interactions between actors and to fulfill that the customer get the product as described, a well thought out communication in a timely manner is important. From an economic perspective and from a quality and time perspective it is of value to investigate communication and information process and what can be perceived as positive or negative.

     

    It is often about spread information and to make it reach the concerned, but it is also important with a limitation of the information. It is good to check that the information has arrived, but it is also important to have confidence in the project participants. Positive factors for strengthening communication may be to ensure that each actor has a common objective, a holistic interpretation in the project. One barrier might be time optimism when important information and essential decisions are delayed. Feedback, positive and negative, is good for the development of projects.

  • 45. Collet, Pierre
    et al.
    Gary, Gérard
    Lundberg, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Noise-corrected Estimation of Complex Modulus in Accord With Causality and Thermodynamics: Application to an Impact test2013In: Journal of applied mechanics, ISSN 0021-8936, E-ISSN 1528-9036, Vol. 80, no 1, p. 011018-Article in journal (Refereed)
    Abstract [en]

    Methods for estimation of the complex modulus generally produce data from which discrete results can be obtained for a set of frequencies. As these results are normally afflicted by noise, they are not necessarily consistent with the principle of causality and requirements of thermodynamics. A method is established for noise-corrected estimation of the complex modulus, subject to the constraints of causality, positivity of dissipation rate and reality of relaxation function, given a finite set of angular frequencies and corresponding complex moduli obtained experimentally. Noise reduction is achieved by requiring that two self-adjoint matrices formed from the experimental data should be positive semidefinite. The method provides a rheological model that corresponds to a specific configuration of springs and dashpots. The poles of the complex modulus on the positive imaginary frequency axis are determined by a subset of parameters obtained as the common positive zeros of certain rational functions, while the remaining parameters are obtained from a least squares fit. If the set of experimental data is sufficiently large, the level of refinement of the rheological model is in accordance with the material behavior and the quality of the experimental data. The method was applied to an impact test with a Nylon bar specimen. In this case, data at the 29 lowest resonance frequencies resulted in a rheological model with 14 parameters. The method has added improvements to the identification of rheological models as follows: (1) Noise reduction is fully integrated. (2) A rheological model is provided with a number of elements in accordance with the complexity of the material behavior and the quality of the experimental data. (3) Parameters determining poles of the complex modulus are obtained without use of a least squares fit.

  • 46.
    Danielsson, Per
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Helander, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics, Byggteknik.
    Vision Nollenergihus: Energiförsörjning av passivhus med sol- och vindenergi2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Climate change is the modern society’s common issue. The developed countries are

    consuming more than what is sustainable, and the climate change due to the use of

    fossil fuels can be seen clearly. EU has specified goals, in order to stop further

    damage, which demand that every member state have to reduce its energy

    consumption by 20 % before 2020 and 50 % before 2050, relative to 1995.

    The Swedish government uses a number of instruments to encourage reduction in the

    usage of energy, but every individual has to contribute to reach the goals.

    With increasing energy price the cost of living is going up. A lot of people are looking

    for ways to save energy and not be affected as much by the increasing price.

    Investments for insulation, replacement of windows and replacing old heating system

    for a new efficient heat pump is getting more and more common.

    This thesis is about investigating the possibilities in becoming independent from buying

    energy for households. The thesis describes ways to use and store the abundant solar

    energy in the summer and transfer it to the winter.

    By building a neighborhood with five so called passive houses and having common

    installations, some costs of the expensive investment can be divided on more than

    one user. Then if the price of energy keeps on rising, it is possible to get a lower living

    cost compared to conventional housing developed according to the Swedish BBR

    demands. This system will become even more profitable when the skills and

    technology is perfected.

  • 47.
    de Joung, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Fuktproblem i oventilerade vindar hos nybyggda flerbostadshus2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Low ventilated cold winds have previously shown to fare better when it comes tomoisture balance. Recent fire requirements has led to that several major constructionfirms have abandoned the use of ventilation at the eaves, this has led to attics withvery limited ventilation. Although these winds should cope well with humidity overtheir lifespan, it have emerged moisture damages to new buildings with this kind ofwind. The reason for this is believed to be large quantities of construction moisturethat low ventilated winds can’t get rid of.This thesis was commissioned by AK-Konsult Indoor Air AB and has audited the coldwind structures from a building built in Örebro with proven moisture problems in theprograms WUFI and WUFI-Bio.The study shows that the winds in their current situation are risk structures whichare in great need of initial help from dehumidifiers to get rid of trapped constructionmoisture.There is uncertainty over how long you should dehumidify the structures, thereforemore extensive measurements should be done.The recommendation to is to dehumidify the structures until they certainly have gotrid of a large portion of the initial construction moisture. A more long lasting solutionis to evaluate the construction type to evade the issue.

  • 48.
    Duanmu, Jie
    et al.
    Functional Materials Center, Laboratory of Polymer Technology, Åbo Akademi University, Åbo, Finland.
    Gamstedt, E. Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Pranovich, Andrey
    Laboratory of Wood and Paper Chemistry, Åbo Akademi University, Åbo, Finland.
    Rosling, Ari
    Functional Materials Center, Laboratory of Polymer Technology, Åbo Akademi University, Åbo, Finland.
    Allyloxy-modified starch with low degree of substitution for fiber reinforced thermoset starch composites2011In: Composites Science And Technology, ISSN 0266-3538, E-ISSN 1879-1050, Vol. 71, no 4, p. 520-527Article in journal (Refereed)
    Abstract [en]

    In the present work dough moulding compound premixes of allyl glycidyl ether modified (AGE)-potato starch, (DS) = 0.2, has been prepared and tested for its fiber reinforced composite properties. The AGE-starch was hydrolyzed with a-amylase under neutral condition for 6 h at 45 degrees C for improved process ability. The grafting and hydrolytic scission was confirmed by nuclear magnetic resonance (NMR) and size exclusion chromatography (SEC), respectively. Homogeneous composite premixes of AGE-starch, wood fibers, various amount of glycerol and ethylene glycol dimethacrylate were successfully mixed with a Brabender-kneader at 55 degrees C and cured by compression molding at 150 degrees C using 2 wt% of dibenzoyl peroxide. Adding 5 wt% of glycerol did not reduce the ultimate strength of the composites: 10% glycerol reduced the strength from 60 MPa to 40 MPa, and 16% glycerol to 14 MPa. The results with 5 wt% glycerol are comparable with earlier achieved results. The water absorption rate increased with increased glycerol content and the mechanical strength of the composites was lost completely when the moisture uptake reached 15 wt%.

  • 49. Duanmu, Jie
    et al.
    Gamstedt, E. Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Rosling, Ari
    Bulk composites from microfibrillated cellulose-reinforced thermoset starch made from enzymatically degraded allyl glycidyl ether-modified starch2012In: Journal of composite materials, ISSN 0021-9983, E-ISSN 1530-793X, Vol. 46, no 25, p. 3201-3209Article in journal (Refereed)
    Abstract [en]

    Microfibrillated cellulose consists of nanoscale bundles of elementary microfibrils prepared, e.g. by the defibrillation of delignified wood pulp fibres in high-pressure homogenizers. In this study, microfibrillated cellulose was used to reinforce a thermoset starch plastic. The starch was modified with allyl glycidyl ether with a degree of substitution of 1.3, which was further hydrolyzed with alpha-amylase for 18 h yielding significantly improved processing properties. Dry premixes of all constituents were prepared by a stepwise drying process before sample manufacturing. The composite was cured by ethylene glycol dimethacrylate initiated with benzoyl peroxide during compression moulding at 150 degrees C. Scanning electron microscopy revealed some degree of porosity in the samples, where the dispersed microfibrillated cellulose network was detectable. Microfibrillated cellulose, even in relatively small additions (2 wt%, 5 wt% and 10 wt%), resulted in composites with rather good hygromechanical properties. The ultimate strength increased with microfibrillated cellulose content and reached values of comparable composites with 40 wt% softwood fibre. Importantly, the dimensional stability in water was much improved compared to similar composites reinforced with substantially larger weight fractions of softwood fibres.

  • 50.
    Edbor, Simon
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Modin, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Punktmolnshantering i anläggningsprojekt: Utvärdering av programvaror för framtagande av markmodell2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    An increased number of participants in the construction industry is asking for accompanying terrain models to the project in order to get a better understanding of the field. When the desire to create buildings that fit together nicely with the surrounding area is increasing, it becomes more and more important to have a broad base of knowledge about the ground on which the building is to be erected. Terrain models are also very useful in the planning of logistics, documentation for landscape architecture projects, and billings for mass calculations.Surveys for creating terrain models can be performed with laser scanning. The advantage of laser scanning is the time-effective surveying, the detailed information as well as the ability of application in complex environments resulting in a cost-efficient project. With this in mind our thesis was defined in collaboration with the company Bjerking AB in Uppsala in order to investigate if there were any softwares suitable for terrain modeling. The idea was created by the company after a previous existing thesis about modeling of buildings from point clouds.The purpose of this study is to examine the possibility of filtering a point cloud and generating of terrain model by surveying with terrestrial laser scanning. The study was conducted in the form of a comparison between six different softwares and the ability to filter noise, and then create a model of the filtered data. The softwares has also been compared between several rate points. In this thesis, a chosen lane at Studenternas idrottsplats, located in central Uppsala, has been scanned containing noise such as cars, light towers, containers, etc. The scanned area resulted in a point cloud and has later on been used in the comparison of software. All six softwares investigated have got different focuses within the field of use of land and construction.The study has shown that the results between the softwares differ significantly. From manual methods to fully automatical, these softwares have been proving their own abilities to perform more or less successful calculations for selecting points and building terrain models. Our terrain models show that all softwares are capable of creating flat surfaces with equal heights, but only a few succeeded in generating slopes. The study also show that a more expensive software does not always guarantee a better result.

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