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1666 Uppsatser om Close to the concrete edge - Sida 1 av 112

Självkompakterande betong vid platsgjutning av anläggningskonstruktioner

By using modern methods of casting concrete, cast in place can get more effective and industrialized. A modern method is self compacting concrete. By using this type of concrete, advantages like improved working environment and rationalized construction can be reached. Because the concrete doesn?t need to be vibrated, the amount of staff on site and the noise can be reduced.

Vindfällning i naturliga och skapade bryn och kanter :

The aim of this work was to study if the edge of the forest is more resistant to heavy winds than the trees located further in from the edge, and how this edge effect changes between different types of tree species and site types. The data was collected from an electric power line going from the north to the south of Sweden. The mean value of the clearcutted area around the power line was 120 meters. The main direction of the storm in January 2005 was west-southwest and thus the power line was a perfect place for gathering a large data set. The main parameter studied was the damage frequency at the edge of the forest compared to the trees located further in from the edge (up to 100 m from the power line). Tree species mixture, soil moisture class, soil type, topography, stand height, stand height of the stand on the other side of the power line and wind exposition was estimated. The results showed a distinct edge effect. The edge of the forest had clearly lower damage frequency for all tree species. A marked difference was observed between tree species and damage frequency.

Studier av habitatval och revirstrukturer hos vassångare (Locustella luscinioides) i Tåkern

The Savi?s Warbler (Locustella luscinioides) is a recently established bird species in a few reedy shallow lakes of southern Sweden and has only been found nesting for the last twenty years. Little is known about the species' habitat preferences, breeding biology and demands for specific territory structures at breeding sites in Sweden. Knowledge of a newly established species? habitat requirements is essential to maintain a viable population and design action plans.

?Annars blir det en grupp av sånna där Redbergspojkar" - En studie om Straight Edge och subkulturer som ett potentiellt kulturarv.

UnderdennastudieharmittsyftevaritattsehurenkulturarvsproduktionskullepåverkasubkulturenStraightEdge,urbådepositivochnegativsynvinkel.StraightEdgeärensubkultursomföddesurenmotreaktionpåpunkensdestruktivaideal.DenärendelavHardcore-­?scenen(HC-­?scenen)ochärbaseradpågrundvärderingenomattavstådroger,alkoholochtobakförrestenavlivet.GenomatttauppfrågorombevarandeochförvaltningavsubkulturenhoppadesjagpåattsXe(StraightEdge)skullekunnablibetraktadurettnyttperspektivdärkulturarvsfrågorkundefåståicentrum.Engenomgåendemetodunderstudienharvaritattgenyanamnåtföreteelserinomsubkulturensomannarsharbetraktatssomvardagliga.AttbenämnaspelningarsomritualerochX:etpådeltagarnashändersomsymbolerhargettmigenchanstilldjupareanalysochnyagrepppåsubkulturen.Underintervjuernamedminainformanterharfråganangåendeinkluderingochexkluderingkommituppochdessatvåbegreppharfåtttastordelavminuppsats.Atthittaenbalansmellanattvarainkluderandeellerexkluderandeverkarvaraettproblemsubkulturentampasmedochminuppsatsharförsöktattbehandladekonsekvensersomkanpåverkasubkulturen,bådepositivaochnegativa.Inkluderingbidrartillenöppensubkultursomkanfåchansenattväxa,medanenexkluderandesubkulturbevararautencitetensomärviktigförattbehålladegrundvärderingarsomsXeäruppbyggdpå.Slutligenharocksåenjämförelsemellansubkulturenochettbefästvärldsarvgjortsförattbreddasynenpåvadettkulturarvkanvara.Därdiskuteraskulturarvsproduktionenskonsekvenserochhursubkulturenkanbådegynnasochhotasavensådanprocess..

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.

Icke-linjära modelleringsteknikerav förspänd betongkonstruktion : Reaktorinneslutningen på Forsmark 3

A new material model, for the FE-program ADINA, has been verified against twoexperiments. One unreinforced concrete beam and one reinforced concrete beam.The model, DF-concrete, has the possibility to estimate true concrete. However theresults indicate that in order to be sure that the estimations are true, there ought tobe data from the true concrete to verify against.Two FE-models have simulated the behavior of a ring-shaped part of the nuclearcontainment vessel. The results from the first, frictionless, model agree with similarsimulations and hand calculations for high pressures in the containment vessel. Thesimulations of the nuclear containment vessel show cracking in the concrete after10-11 bars of over pressurization.

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..

Miljövärdering av resurssnål betong med införande i BIM

This thesis aims to illustrate how environmental impact can be reduced, through the use of lean concrete. It also illustrates how environmental data can be applied to a house through implementation with BIM. In this study a unique concrete structure developed by Swedish Cement and Concrete Research Institute is assessed for environmental impact, by calculating the carbon dioxide equivalents using LCA methodology. The construction is a sandwich element where the concrete is made ??up of three layers.

Träd och buskar i kantzoner : en undersökning av kanteffekter i några av östersjöregionens skogar

Around the world, forests are generally being fragmented and as plant populations decline in both sizeand number of individuals, the genetic variation will also decrease whitch in the end leads to totalextinction of the plant. In this paper, I wanted to investigate what specific species of trees and shrubsyou usually find in the edge and core habitats in some of the forests in the Baltic Sea region. I alsowanted to identify the edge effects and their sources and finally compare the results between thedifferent regions.The data sources used are derived from the ongoining research project Landscape structures, patterns ofbiodiversity and conservation strategies in the Baltic Sea region by Kari Lehtilä, Patrik Dinnétz ochTiina Vinter who have made a record of all herbaceous plant species in four randomly chosen forestregions situated around the Baltic Sea: Estonia, Skåne, Södermanland and Germany. I made statisticalanalyses, using the computer program R, concerning the distribution of species in the edge habitats ofthe forests as well as in the core habitats. I performed generalized linear models and then variationanalyses with the factors light and biomass in order to investigate wether edge effects might appear dueto these factors.

Gränsen mot omgivningen : hur formas stadens kanter?

The edge or the fringe of the city is often the first part of the city we encounter, and our perception of it will probably color the image we make in our minds of the city as a whole. Even though the fringe of the city is important to the image of the cityscape it has not very often been the direct object of attention either in planning, building or even in the heads of the masters, when big ideas were formed. More often than not the fringe seems like something that just happened over time due to separate landowners, businesses or actions of other financially strong operators. The aim of this essay is to try to describe the history of the city edge in Sweden, from the very first town in the 10th century until today?s expanding mosaic of different ideas and styles as well as to bring some clarity and order into some of the different ideas and ideals in the planning of the edge in different eras and to review how the edge has been shaped and used.

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.

Från singelmedia till multimedia, En studie om förutsättningarna för ett mediehanteringssystem

Teknomedia är ett utvecklingsbolag för nya medier inom Norrköpings Tidningars koncern. Teknomedia producerar bland annat produkt? och företagspresentationer, reklamfilm samt webblösningar. De har även utvecklat Edge som är ett publiceringsverktyg för enkel publicering av webbsidor.Under 2005 kommer en lokalTV?kanal att startas av Norrköpings tidningar som ett komplement till morgontidning och webb.

EN TOTALKOSTNADSJÄMFÖRELSE MELLAN CELL-, SKUM- OCH LECA-BETONG

This report provides a comparison between the products cellular concrete, foam concrete and LECA concrete. The questions to be answered during the work is how the cellular concrete stands up in cost terms to the existing competitors on the market, how the concrete products differ in design work, and in which situations the concrete varieties are preferred to use.Cellular concrete is a variant of ordinary concrete, with the difference that the ballast is exchanged from stone materials to expanded polystyrene beads (EPS). This substitution gives a product with higher insulation values but lower weight than ordinary concrete.The work was carried out by designing a survey which was sent to two hundred randomly chosen companies across Sweden, to see the building industry?s opinion of the product cellular concrete. The survey showed that cellular concrete was equals its competitors in terms of price, while the product was said to be more flexible, quicker and easier to cast.Then some of the companies, who participated in the survey, were interviewed to see more carefully, how the price, the workmanship and the time for casting and dehydration differed between the products.

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..

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.

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