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2363 Uppsatser om Concrete structure - Sida 2 av 158
Betong - Förvånansvärt lättflytande!
Concrete is a very common construction material. It´s characteristics are strength, durability and formablility. Superplasticizer is a common admixture, which changes the properties of concrete.
Today (spring 2007) there are no certian mathematical methods to calculate the required percentage of this admixture needed to give the necessary set slump flow in the overall concrete recipe.
Concrete batching companies must therefor experiment with different amount of superplasticizer in order to meet the specified slump and strength.
The purpose og this report is to investigate if any mathematical relation can be established between the amount of superplasticizer used and the slump flow achieved.
After carrying out some practical experiments using four different superplasticizers a direct relationship can be establish between the percentage of admixture used and the slump/flowability achieved. Unfortunatly at present due to the numerous variables, the calculation of mathematical formula can not be achieved..
DU#kulturskolan : En kvantitativ studie om hur elever ser på sitt engagemang då de musicerar och undervisas på kulturskolan.
The Sand Catcher The thesis project The Sand Catcher investigates the encounter between permanent structures and an ever-changing landscape. The migrating sand dune Råbjerg Mile in northern Denmark is 40 meters high and moves more than 15 meters every year. By introducing a solid structure on the site, the fast movement of the sand dune is emphasised and thereby our view of time and space.Through intuitively building models with varied openings and densities I investigated how architectural elements react with sand. From these experiments a series of spatial features and effects were found, generated from the meeting with the sand.The Sand Catcher is a solid and permanent structure. The sand is the liquid element that generates new spaces, circulations and experiences.
Utmattning av vägbroar i armerad betong enligt eurokoder
Since 1 January 2010 it is a requirement to use the European standards, Eurocodes, in Sweden when constructing bridges. One chapter that has caused an extra amount of problems for the engineers is the one about fatigue analysis, which resulted in us doing this thesis.To do this we had to read all of the Eurocodes that direct, or indirect deals with fatigue and calculating of such. We have read the background documents for the Eurocodes and master?s thesis in the subject. We also studied the calculations of bridges constructed by different construction firms.We have chosen to limit the thesis to discuss only road bridges made of concrete due to the lack of method for verification of concrete in the national appendix.
Sandfångaren : En undersökning av mötet mellan en byggd struktur och ett landskap i förändring
The Sand Catcher The thesis project The Sand Catcher investigates the encounter between permanent structures and an ever-changing landscape. The migrating sand dune Råbjerg Mile in northern Denmark is 40 meters high and moves more than 15 meters every year. By introducing a solid structure on the site, the fast movement of the sand dune is emphasised and thereby our view of time and space.Through intuitively building models with varied openings and densities I investigated how architectural elements react with sand. From these experiments a series of spatial features and effects were found, generated from the meeting with the sand.The Sand Catcher is a solid and permanent structure. The sand is the liquid element that generates new spaces, circulations and experiences.
Behovet av en genomtänkt kommunikationsstruktur- en studie av ett projektorienterat företag
Every organization goes through the same lifecycle. Through every step in the transformation to a better organization the communication structure changes. In this report there are examples of the communicational disadvantages that is connected to the communicational structure.By choosing to not have a formal communicational design, the manager takes a risk in spreading the information, the interaction, the control and the balance in creativity and constraint.This case organizations problem is that some parts of the organization has made more progress in the communicational structure than other parts. In this case the Collectivity structure has met the Formalized structure.Tha structural differences has came to affect the way of sharing information and it has become a situation where the information about the products is not stored in a safe way from a quality point of view. There is a gap between the two different ways of communicate.In this report I have created a model to identify problems in the communication structure.
Prefabricerade stödmurar i betong :
This is a booklet with information and inspiration about precast retaining walls. The three chapters contain information about concrete as a material, how the surface of the wall can be altered, and a chapter with ideas for a new precast wall. I have obtained information through books, interviews, lectures and fairs. The retaining walls on the market do not correspond to the requirements of the Landscape Architects I have interviewed. I have therefore considered their opinions in the chapter containing my new ideas for new retaining walls.
The Capital Structure Puzzle of SME's - Evidence from the Swedish Security Industry
The purpose of this thesis is to ascertain the main determinable factors of Swedish SMEs capital structure decisions and to investigate whether existing capital structure theories are applicable on Swedish SME financing. We have used panel data to run regressions of various capital structure determinants on three measures of capital structure; short- term debt, long-term debt and total debt. We found that growth opportunities, profitability and age are the most important capitalstructures determinants for our sample. Firm size shows a small explanatory result but the effective tax rate and the asset tangibility do not seem to explain the capital structure at all. Thematurity matching principle is considered significant..
Lek och lärande : En studie av vad lärare och elever associerar ett laborativt arbetssätt i matematik med
During recent years, the trend of Swedish students? negative performance and results in mathematics has been discussed. It is agreed that a change in teaching methods is necessary in order to solve this issue. Thus we found it interesting to take a closer look at an alternative way of teaching. The purpose of this study was to find out what teachers and students associate concrete mathematics with and make a comparison between them.
Försöksmetod för automatisering av kvalitetssäkring av SKB
Within all industries, there is a change in working time required; this also includes the construction sector. However, the way construction sectors are differentiated is by not having been given the opportunity to be practiced or tested. The aim of this thesis that we have done in collaboration with the Concrete Industry was to investigate the possibility of developing an automated method for quality assurance of SKB at the site. The idea is to make the O-funnel to be more utilized and therefore ensuring that the appropriate concrete quality is provided which eventually would lead to a better development in the production process.The project has involved theoretical work and laboratory experiments. The theoretical work gave us a good foundation at the beginning of the project. After gathering the information and material, the laboratory experiments began by SCC in their laboratory in Hammarby. The collected data from the various laboratory tests formed the foundation for trying to relate measurements for consistency of SCC with each other and therefore find out how measurements from O-funnel varies with different concrete mixtures.
Projektering av ett småhus med fördjupning i uppvärmningssystem
This report aims to examine the design of a passive house. The design addresses the selection ofmaterial, sizing and selection of both building services systems and building technical features suchas load-bearing framework and moisture control. Interior layout is designed for a family of twoadults and one child.A big part of the report is devoted to an in-depth comparison of three different wall constructions ofpassive house standard. The structures that have been compared are a lightweight timber structure, aheavier Concrete structure and a sandwich wall of the brand Weber Leca. The report covers variousaspects such as air flow, wall thickness, the risks associated with the construction, U-value, thermalbridges, power consumption, price, and assembly costs.
Passivhus : En jämförelse mellan olika byggnadstekniska lösningar för ytterväggar
This report aims to examine the design of a passive house. The design addresses the selection ofmaterial, sizing and selection of both building services systems and building technical features suchas load-bearing framework and moisture control. Interior layout is designed for a family of twoadults and one child.A big part of the report is devoted to an in-depth comparison of three different wall constructions ofpassive house standard. The structures that have been compared are a lightweight timber structure, aheavier Concrete structure and a sandwich wall of the brand Weber Leca. The report covers variousaspects such as air flow, wall thickness, the risks associated with the construction, U-value, thermalbridges, power consumption, price, and assembly costs.
Organisering av ojämställdhet - En studie av kvinnors möjligheter att nå chefspositioner i Försvarsmaktens personalstab
This thesis aims to examine why women are prevented from attaining high positions in organizations. By executing a case study through qualitative interviews with employees from the Human Resource Department at the agency for Swedish Armed Forces, this study presents eight general and specific explanatory factors that hinder women from making a vertical career. The general factors include that women are discriminated against, women are perceived as less competent, men have created organizations and it is easier to recruit men. The specific factors include that a hierarchical organizational structure is correlated to inequality, that both the agency for Swedish Armed Forces and leadership are associated with masculinity and that women with civil competence face double misfortune. The division between general and specific factors indicate that the explanatory factors vary between organizations, which among other things implies that equality work should be tailored for the specific organization.
Stomme i småhus ! : - En teoretisk studie av olika bärande vägglösningar !
This report aims to examine the design of a passive house. The design addresses the selection ofmaterial, sizing and selection of both building services systems and building technical features suchas load-bearing framework and moisture control. Interior layout is designed for a family of twoadults and one child.A big part of the report is devoted to an in-depth comparison of three different wall constructions ofpassive house standard. The structures that have been compared are a lightweight timber structure, aheavier Concrete structure and a sandwich wall of the brand Weber Leca. The report covers variousaspects such as air flow, wall thickness, the risks associated with the construction, U-value, thermalbridges, power consumption, price, and assembly costs.
Stenmjöl eller naturgrus i betong : En jämförande studie
The objective of this thesis is to examine the difference in workability in fresh concrete, when crushed fine aggregate replaces natural gravel. The shape of the fine aggregate, packing and flow of six crushed material and three natural materials will be determined by easy studies, the results will be compared with a slump cone test..
Datormodellering av en värmelagrande betongväggs inverkan på det termiska klimatet i ett växthus
This report describes the building of a computer model that makes it possible to simulate the thermal climate in a greenhouse. The computer model is built on the physical theory of heat exchange that occur in a greenhouse, such as radiation and convective heat exchange. The model also includes the heat storage that is active in a greenhouse.The computer model is used to simulate the thermal climate in a greenhouse under three periods, winter, spring and summer. It also investigates which effect a concrete wall has on the thermal climate in a greenhouse. The purpose of putting a concrete wall in the greenhouse model is to investigate the possibility to store heat during the day and then use this heat when the temperature drops during the night.The result from the simulations shows that a concrete wall levels the big difference in temperature that normally occurs under a day in a greenhouse.