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6095 Uppsatser om High-performance concrete - Sida 2 av 407
Användning av högpresterande betong i husbyggnader : Materialförsök och modellering
Idag är intresset för högpresterande betong (HPB) växande runt om världen då fördelarna är många, eftersom slankare, tätare, starkare och lättare konstruktioner kan tillverkas. Detta examensarbete handlar om materialförsök och modellering för en typ av HPB som ska användas i husbyggnation. Arbetet inleddes med materialförsök i färskt tillstånd, där god gjutbarhet och konsistens eftersträvades. Utgångspunkten var från ett grundrecept med två olika ballastsorter (slaggballast med flygaska och krossballast från asfaltindustrin med silikastoft), vilka namngavs till pilotförsök 1 och pilotförsök 2. Vidare valdes pilotförsök 1 att provas i hårdnat tillstånd då det visades att det var mer ekonomiskt lönsam eftersom ballasten inte behövde siktas, lägre vct tillhandhölls och att flygaskan som användes i pilotförsök 1 är billigare än silikastoft som användes i pilotförsök 2. Resultaten efter 28 dygn för de materialförsök som utfördes i hårdnat tillstånd var:Tryckhållfasthet; 141,9 MPaDraghållfasthet; 7,0 MPaBöjdraghållfasthet; 10,0 MPaElasticitetsmodul; 46,4 GPaKrympning efter 56 dygn; 0,5 ?Samtliga försök utfördes enligt svenska standarder (SS). Dessutom vidareutvecklas och förbättrades ett redan arkitektoniskt gestaltat Attefallshus ur ett konstruktions- och hållbarhets perspektiv, där fokus låg på transport- och produktionsförutsättningar.
Inverkan av tvång i gjutfogar och i betongkonstruktioner på
elastiskt underlag: Influence of Restraint in Casting Joints
and in Concrete Structures on Resilient Foundation
In this report, the risk of cracking in joints and/in adjacent concrete is estimated by checking shear forces in joints and the ratio between the actual maximum principal stress ant the actual strength of the concrete. The shear force has been estimated both by simple methods as well as by two-dimensional calculations. The risk of cracking in the concrete and/or in the joints is estimated with the computer program ConStre. The restraint from a resilient foundation or rock on a young concrete construction is estimated by a simple method that is exemplified. It is shown that the restraint can be neglected in some cases.
Omkonstruktion av testrigg för småskalig ångsmotor
The actual project presents the development of a testing rig for a steam engine. A short overviewabout the development of steam engines is presented, until arriving to the development of thepresent engine, which will require to be tested in different ways.The testing rig studied on this project (based on a Lanchester engine) will be used to testdifferent materials and layouts for the group Piston-Cylinder.The engine is a high performance steam power engine, which is going to have a highpower/dimensions ratio, what will lead to require high performance components and materials.An introduction to the testing rig is presented, and the entire design project is done in order toreplace the disappeared documentation of the current testing rig, built on the 1970?s. Also somemodifications done in the original testing rig are presented, as well as some detected problemsand their possible solutions..
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.
Värdering av prestation och riskbeteende i ung ålder : Finns det ett samband?
This paper is a study how students at a high school in Falun, Sweden, estimates theirperformance in an upcoming math test which is then compared with the actual grade thestudent performed. The students who participated also answered questions related to ?risksituations? to examine whether there is a correlation between how students estimate theirperformance in the context and their risk behavior, and if the students act like economicmodels assume. In agreement with previous studies, the boys in the survey tended to beoverconfident in their performance. The girls in the study were neither over- norunderconfident in her performance and no significant difference in the estimation of one'sperformance between the sexes could be proven.
Övergång till helkrossballast : En studie för Strängbetongfabrikerna i Veddige och Herrljunga
This exam report has been developed in association with Strangbetong AB, Sweden.The natural gravel that is being used as fine aggregate for concrete production today is an ending natural recourse and the Swedish government has decided to strongly reduce the extraction from the year of 2020. The only reasonable replacement is aggregates from crushed rocks but this material has other properties than natural aggregates. The concrete manufacturers now have to learn how to use these new fine aggregates in a cost effective way in order to ensure the quality of their concrete production.In this project, crushed aggregates and combination of crushed and natural aggregates have been tested with existing formulas for fresh concrete. The two parameters yield stress and plastic viscosity have been measured which gives a good description of the workability of the fresh concrete. Different methods to make measurements on the dry fine aggregates, has also been tested, to find out if there is any correlations between these parameters and the parameters from the measurement on the fresh concrete..
Syskonplacering, studieresultat och prestationsbehov hos gymnasieelever
The aim of this study was to investigate whether there is a correlation between birth order, academic performance and need for achievement. 166 students from Alvesta Gymnasium/ High school and Växjö Fria Gymnasium/ High school participated in the study. The result showed a significant correlation between birth order and study result, but unlike previous studies this study showed that it was the youngest siblings that had the best academic performance. Furthermore, a significant correlation between academic performance and need for achievement was found, also that higher need for achievement results in higher academic performance. The study also showed that there is a significant correlation between birth order and need for achievement, and it is the youngest children that have the highest need for achievement.
Frånluftsvärmepumpens möjligheter i flerbostadshus
If a building is heated by a heat pump, it is of high importance that the heat pump has a high coefficient of performance. An exhaust air heat pump extracts heat from the building?s exhaust air. The air has a relatively high and constant temperature all year around, leading to a high seasonal coefficient of performance. This thesis examines whether it is profitable to complement an exhaust ventilation system with an exhaust air heat pump in an apartment block that already has geothermal heat pump, district heating, oil- or biofuel heated system.
Migrating Mesh SkinningDeformation Functionality fromRSX to SPUs on thePlayStation ® 3
In game development, performance is everything and the Playstation 3 provides a unique platform for utilizing parallelization of code to achieve extremely high performance. In this master?s thesis the issue of animation with smooth skinning is migrated from being a GPU process to becoming a parallelized and 358% faster process. This method is incorporated in an existing commercial game engine and integrated in a currently in development title for the Playstation 3. An in-depth study covers parallel processors, the CELL processor, used in the Playstation 3, and how contemporary industry leading game developers are utilizing the same unique architecture to increase their own games? performance..
Metodik för fastställande av bärförmåga på befintliga betongkonstruktioner
Many buildings are now nearing the end of their service life. This applies to both the older houses from the 40's and 50's to the million project houses that did not prove to be as sustainable in the long run. Often there is a desire to extend the service lifetime, but to do that you need to make detailed inspections. The Folkets hus in Gävle is one of those buildings that is in need of renovation and to fulfill the new requirements that must be met in today's buildings. It is desired to make the buildings rentable space more attractive and to extend the building with two more floors.
Behuggning av betongytor: ett test av hantverksmetoder
During the latter half of the 18th century, when concrete started seeing general use in
modern cities, the use of different methods to give the concrete a finished surface texture
saw use. One of these was using different methods of mechanically altering the surface using
a slew of cutting and crushing techniques with mallet and chisel. This was done in order to
hide the often dull and gray look of concrete, and allude to other more expensive and
luxurious stones. The work would possibly have been done by experienced stonemasons,
using much of the same techniques and tools they would have used while working natural
stones. Or did they? This essay explores, through the use of traditional handcrafts and tools,
the claim that the working of concrete surfaces can be done with the same tools and skillset
as the working of natural stone.
Smarta prefabmoduler för småhus i betong
This report examines the possibility of developing a modular system for concrete homes that cancontribute to greater diversity of today's market. The issue was whether it ? from a competitive pointof view ? is possible to produce smart prefab modules that customers themselves can combine to avilla. The report addresses the question how the modules and wall panels should be designed for thegreatest variety of floor plans.With regard to what is asked of the customer interviews where held for the purpose ofunderstanding concrete's popularity and elements of high value in their homes today. The answersfrom the interviews laid ground for four prototype homes which were made to demonstrate how theelements can be combined to achieve different types of houses..
Lönar sig Supply Chain Management för mindre företag?
Purpose - To analyze the relationship between supply chain management maturity, supply chain performance and financial performance in small and medium-sized enterprises (SME:s).Design/methodology/approach - The data comprises 15 SME:s that participated in a local logistic study in Gävleborgs län. The levels of supply chain mature within these firms were based upon an interview study and the financial performance of the firms was then examined using financial reports-based data.Findings -The results of this study indicate that there is a strong relationship between SCM maturity and SC performance in SMEs, some relationships between SCM maturity and financial performance, as well as some relationships between SC performance and financial performance. This means that if firms use maturity indicators in the SCOR areas to improve their processes, they will most likely achieve a positive effect on supply chain performance and probably also on financial performance. The result implies that the supply chain maturities in these firms are higher than expected with no one at the adHoc level.While this study is based on a rather small number of participating firms, it would be valuable to further test the significance of the indicated correlations between SCM maturity and performance in a large-scale survey.Research limitations/Implications - The research is an attempt to understand supply chain maturity and it´s implication on financial performance. Developing supply chain maturity is an opportunity for a company to gain superior performance.
OMBYGGNAD AV TRAFIKPLATS : Ekhagsmotet i Jönköping
We have the tradition in Sweden to build villas and houses with a wooden framework. It has become natural for us because we have so much forest in our country. Building with wood has advantages, it is easy to process, but also disadvantages, as it is sensitive to moisture.Finland has long made use of the thermal blocks to build villas. It is a type of bricks that are a bit like a sandwich element, with a core of EPS and concrete on both sides of the core material. The concrete is hollow, so that after the walls has been bricked up you pour concrete into the hollow bricks.The issue of this report is to find out if concrete can be an alternative to wood as framework material in villas.
Analys och förbättringsförslag för riktkopplardesign
Ericsson develops a new stripline directional coupler. Its design is described in appendix B and differs from the directional couplers Ericsson uses in current products. The new directional coupler will be used for transmission power measurement in future UMTS 3G base stations.The most important parts of directional coupler theory are presented. It is necessary to study this theory to understand how the coupler works and how it should be designed to get good performance.Optimal directional coupler termination component values to get high directivity and broad directivity bandwidth have been investigated.The trim screws trim ranges have been studied.A simple analysis of serial production performance when termination component tolerances are taken into consideration has been done.The resistance components reactive (inductive/capacitive) characteristics at 2.14 GHz have been analyzed.The directivity performance limitations of the directional coupler, when Ericsson?s band pass filter is connected, are investigated.Design changes leading to better performance are proposed.