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With increased demand for housing in Sweden's metropolitan regions, it is of greatimportance to meet the need and build more. The supply of housing is governed byaccess to land and what it costs to build apartment houses. In Sweden, there is ahistory of cartel formation of contractors and at the turn of the millennium, thegovernment invested funds to create increased price transparency in theconstruction sector. Based on this, the purpose of this project is to investigate how itis possible to today produce housing more economically, while maintaining quality.The study is limited to the purchase of prefabricated hollow core and load-bearingwall elements in both concrete and wood. The goal is to be able to compare prices ofthese construction parts between Swedish and foreign suppliers. The foreignsuppliers are limited to the ones operating in the Baltic countries and Poland. Thus, itmust be investigated which of the wooden or concrete frames is most economicallyprofitable, what opportunities there are with international purchases of frameelements and what should be taken into account in international purchases. / I och med ökad efterfrågan på bostäder i Sveriges storstadsregioner är det av vikt atti samma takt öka utbudet. Utbudet styrs av tillgång till mark samt vad det kostar attbygga. I Sverige finns en historia av kartellbildning av byggföretag och regeringensatte vid millennieskiftet in medel för att skapa ökad pristransparens inombyggsektorn. Med bakgrund i detta är syftet med examensarbetet att undersöka hurdet idag går att producera bostäder mer ekonomiskt, med bibehållen kvalitet iåtanke. Studien avgränsas till inköp av prefabricerade håldäck och bärandeväggelement i betong respektive trä. Målet är att kunna jämföra priser av dessakonstruktionsdelar mellan svenska och utländska leverantörer. De utländskaleverantörerna avgränsas till att verka inom baltikum och Polen. Således ska detutredas vad utav trä- eller betongstomme som är mest ekonomiskt lönsamt, vilkamöjligheter som finns med internationella inköp av stomelement samt vad som börtas hänsyn till vid internationella inköp.De risker som finns kopplade till just internationella inköp är bland andra risk attprodukten inte stämmer överens med vad som avtalats och leveransförseningar.Logistikrisker begränsas med hjälp av avtal reglerade utifrån det internationellaregelverket Incoterms. Det finns även politiska och valutarelaterade risker medinternationell handel.ISO 9000 är ett kvalitetsledningssystem som ligger till grund för att företag ochorganisationer ska kunna säkerställa att kvaliteten i deras arbete svarar upp motkundens behov och krav. ISO 14000 samlar standarder inom miljöledningssystem.Intervjuer av sex svenska och fem utländska leverantörer om pris och kvalitetsarbetegav intressanta resultat för studien. Samtliga utländska leverantörer är certifierademed ISO 9001 samt ISO 14001. Två av sex svenska bolag har ISO9001-certifieringen och hälften ISO 14001-certifieringen. Att köpa prefabriceradebetongelement är enligt studien inte ekonomiskt lönsammare i utlandet, det är detdäremot att köpa träelement.

Three components, a pallet, packaging, and material handling equipment, of the unit load portion of the supply chain are physically and mechanically interacting during product storage and shipping. Understanding the interactions between two primary components, a pallet and packaging, in a unit load is a key step towards supply chain cost reduction and workplace safety improvement. Designing a unit load without considering physical and mechanical interactions, between those two components, can result in human injury or death caused from a unsafe workplace environment and increased supply chain operating costs, due to product damage, high packaging cost, disposal expense, and waste of natural resources. This research is directed towards developing predictive models of the compressive stress distributions using the principle of the beam on an elastic foundation and experimentally quantifying the compressive stress distributions. The overall objective of this study is to develop a model that predicts compressive stress distributions at the interface between a pallet deck and packaging as a function of: pallet deck stiffness, packaging stiffness, and pallet joint fixity. The developed models were validated by comparison to the results of physical testing of the unit load section. Design variables required for modeling included Modulus of Elasticity (MOE) of pallet deckboards, Rotation Modulus (RM) for nailed joints, and packaging stiffness. Predictive models of the compressive stress distributions were non-uniformly distributed across the interface between pallet deckboards and packaging. Maximum compressive stresses were observed at the deckboard ends over stringer segments. All predictive compressive stress distributions were influenced by pallet deck stiffness, packaging stiffness, and joint fixity. The less the joint fixity the greater the pallet deck deflection. The stiffer deckboards are more sensitive to joint fixity. For predictive compressive stress distribution models, the measure of the stress concentrations was the Compressive Stress Intensity Factor (SIF), which was the ratio of the estimated maximum compressive stress to the applied stress. Less stiff pallets and stiffer packaging resulted in greater SIF for all end condition models. SIF was reduced by stiffer joint, stiffer pallet deck and more flexible packaging. The stiffer the pallet deck and pallet joint the greater the effective bearing area. The lower stiffness packaging resulted in the greater effective bearing area with all three packages. The predicted effective bearing area was more influenced by pallet deck stiffness than the packaging stiffness. The developed prediction models were validated by comparison to experimental results. All prediction models fell within 95% confidence bounds except the 3/8-inch deck with free ends and 3/4-inch deck with fixed ends. The difference between predicted and measured results was due to a limitation in pressure sensor range and test specimen construction for the free end model and fixed end model, respectively. The results show effects of pallet deck stiffness and packaging stiffness on SIFs with percentage changes ranging from 2 to 26% (absolute value of change) for all three end conditions. The sensitivity study concluded that changing both pallet deck stiffness and packaging stiffness more significantly influenced the SIFs than bearing areas. / Ph. D.

Este estudo fundamenta-se na análise numérica, via elementos finitos, de pontes em vigas mistas; considera-se a interação de todos os elementos que compõem a estrutura na transferência dos esforços até os apoios. Inicialmente apresenta-se um estado da arte sobre o projeto, execução e análise de pontes em vigas mistas, identificando as simplificações e deficiências existentes no cálculo destas estruturas. O estudo do comportamento estrutural de tabuleiros mistos foi abordado do ponto de vista tridimensional, sendo para isto modelados e analisados tabuleiros com 8, 10, 12, 14, 16, 18, 20, 22, 24 e 26 m. de vão mediante a utilização do programa ANSYS, versão 5.4. Foi estudada a influência que a presença de contraventamentos, espessura da laje, vão e posição da carga móvel na seção transversal exercem na distribuição de cargas nas vigas, sendo para isto considerado comportamento elástico-linear. Realizou-se também uma abordagem ao estudo da redundância estrutural de tabuleiros mistos considerando as não linearidades física e geométricas do conjunto. Foi verificado que tabuleiros sobre duas e quatro vigas mantêm o equilíbrio estático após que uma das vigas sofre fratura, sem experimentar grandes deslocamentos (inferiores ou ligeiramente superiores ao limite L/500). / This work is based in the numerical analysis, by finite elements, of bridge decks with composite beams; in this study the interaction of all the elements that compose the structure is considered in the transference of the efforts to the supports. lnitially, a state of the art on the design, construction and analysis of composite bridge decks is presented, identifying the simplifications adopted, lack of information at the present on the subject and aspects that need further studies on this bridges. The study of the structural behavior of composite bridge decks was approached from a three-dimensional point of view, modeling and analyzing composite decks with 8, 10, 12, 14, 16, 18, 20, 22, 24 and 26 m of span by using the software ANSYS, version 5.4. The influence that the bracing system, thickness of the slab, span and live load position on the deck, over the load distribution in the composite beams, considering linear-elastic behavior, was studied. An approach to the study of the structural redundancy of composite bridge decks was also made, considering the physical and geometric nonlinearities of the structure. lt was verified that decks consisting of two and four composite beams maintain the static equilibrium after the fracture of one of the beams, without large displacements (inferior or lightly superior to the limit L/500).

Este estudo fundamenta-se na análise numérica, via elementos finitos, de pontes em vigas mistas; considera-se a interação de todos os elementos que compõem a estrutura na transferência dos esforços até os apoios. Inicialmente apresenta-se um estado da arte sobre o projeto, execução e análise de pontes em vigas mistas, identificando as simplificações e deficiências existentes no cálculo destas estruturas. O estudo do comportamento estrutural de tabuleiros mistos foi abordado do ponto de vista tridimensional, sendo para isto modelados e analisados tabuleiros com 8, 10, 12, 14, 16, 18, 20, 22, 24 e 26 m. de vão mediante a utilização do programa ANSYS, versão 5.4. Foi estudada a influência que a presença de contraventamentos, espessura da laje, vão e posição da carga móvel na seção transversal exercem na distribuição de cargas nas vigas, sendo para isto considerado comportamento elástico-linear. Realizou-se também uma abordagem ao estudo da redundância estrutural de tabuleiros mistos considerando as não linearidades física e geométricas do conjunto. Foi verificado que tabuleiros sobre duas e quatro vigas mantêm o equilíbrio estático após que uma das vigas sofre fratura, sem experimentar grandes deslocamentos (inferiores ou ligeiramente superiores ao limite L/500). / This work is based in the numerical analysis, by finite elements, of bridge decks with composite beams; in this study the interaction of all the elements that compose the structure is considered in the transference of the efforts to the supports. lnitially, a state of the art on the design, construction and analysis of composite bridge decks is presented, identifying the simplifications adopted, lack of information at the present on the subject and aspects that need further studies on this bridges. The study of the structural behavior of composite bridge decks was approached from a three-dimensional point of view, modeling and analyzing composite decks with 8, 10, 12, 14, 16, 18, 20, 22, 24 and 26 m of span by using the software ANSYS, version 5.4. The influence that the bracing system, thickness of the slab, span and live load position on the deck, over the load distribution in the composite beams, considering linear-elastic behavior, was studied. An approach to the study of the structural redundancy of composite bridge decks was also made, considering the physical and geometric nonlinearities of the structure. lt was verified that decks consisting of two and four composite beams maintain the static equilibrium after the fracture of one of the beams, without large displacements (inferior or lightly superior to the limit L/500).