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27 Uppsatser om Ultrafine limestone filler - Sida 1 av 2

Betongens hållfasthetsutveckling vid användning av olika ersättare för portlandklinker : En laborativ studie

Tillverkning av portlandklinker står för ungefär fem procent av världens totala koldioxidutsläpp. Det finns därför ett allmänt intresse att minska användandet av portlandklinker. Klinkern kan antingen ersättas av andra cementerande material, eller så kan nya cementsnåla recept utformas. I den här rapporten har två cement med inmald flygaska respektive slagg från Cementa AB undersökts. För att undersöka klinkerersättnings-materialens potential har tester för tryckhållfasthet, uttorkningskrympning, bindetid, värmeutveckling och arbetbarhet utförts.

Tryckhållfasthet för resurssnål betong : Utvärdering i tävling av högsta tryckhållfasthet för resurssnål betong

Betong är vårt vanligaste byggmaterial men cement står globalt sett för 5 % av CO2-emissionerna. Med detta som bakgrund så har CBI Betonginstitutet anordnat en tävling, där målet är att nå den högsta tryckhållfasthet i en resurssnål betong, med enbart 200 kg cement per m3. Syftet med denna rapport är att utvärdera tävlingen, vilket har utförts genom en omfattande litteraturstudie. En första analys av de olika betongrecepten medförde att olika grupperingar kunde urskiljas. Ur dessa fanns det tre stycken vars resultat var väldigt bra. ? Concrete Innovation Centre, som med ett lågt vct, stora mängder granulerad masugnsslagg (81 %) och lite silikastoft (5 %), uppnådde en tryckhållfasthet på 80 MPa vid 28 dygn och 95 MPa vid 56 dygn. ? CBI Stockholm, som genom användandet av ulltrafint filler och silikastoft (4,8 %), uppnådde en tryckhållfasthet på 84 MPa vid 28 dygn och 98 MPa vid 56 dygn. ? Thomas Concrete Group som genom att ersätta cementet med en medelmåttig mängd granulerad masugnsslagg (54 %), liten mängd flygaska (9 %), kalkfiller och silikastoft (5 %), uppnådde en tryckhållfasthet på 94 MPa vid 28 dygn och 98 MPa vid 56 dygn. Det finns således tre recept som vidare studier kan vara rättfärdigade på, de tre ovan nämnda. Det bör tilläggas att en imponerande tryckhållfasthet på nästan 100 MPa, kan uppnås i en betong med enbart 200 kg cement per m3. .

Tanklock med förbättrat grepp

This degree project was conducted in collaboration with Husqvarna AB, the headquartersof which are located in Jönköping. The aim was to further develop the filler cap found onmore or less the whole of the company?s range of chain saws, in order to make it moreuser friendly.The present filler cap is not easy to open and close, especially when wearing gloves, andunder difficult conditions, which creates problems and prolongs filling time.On the basis of market surveys, different prototypes and tests, we have created anergonomically improved cap of a new shape, which can be moved in the axial direction,thus making filling easier..

Structure and tree diversity of lowland limestone forest on Seram Island, Indonesia

There have previously been very few studies of forests on Seram Island in the Eastern Indonesian archipelago and none before on lowland limestone primary forests. The COLUPSIA project on collaborative land use planning has therefore chosen Seram as one of two project sites. The objective of the COLUPSIA project is to establish collaborative and equitable land use planning. In order to achieve its objective the COLUPSIA project aims to improve understanding of traditional resource management and how it interacts with governmental systems, as well as enhancing knowledge about tropical landscapes and ecosystem services.The aim of this study was to contribute to the COLUPSIA project through describing lowland limestone forest on Seram Island in respect to (1) forest structure, (2) tree species richness and (3) tree species composition. We set up 5 plots, each of 0.2 ha, at one site, Mawalai, and collected data on tree variables (tree diameter ?10 cm) as well as for some other life forms and environmental data.

Kalkbrottstvisten i Bunge Ducker : En ACF-analys av två kolliderande riksintressen

Abstract This thesis is based on a case study of the drawn out legal process on the question of establish a limestone quarry in Bunge Ducker in north Gotland (Sweden). The current fields are located next to areas that are protected by virtue of being EU-certified Natura 2000-areas. Despite this, the Swedish governments and courts have not agreed in witch national interest that should be prevail when decisions are made on this issue. This phenomenon are reflected in the judicial process and different court have evaluate information differently in the case. A change among governmental actors where priority is given to the importance of national interest have occur in the later part in the process.

Fosforavskiljning i reaktiva filter vid småskalig avloppsrening

An excessive input of nutrients to lakes and other water bodies has created a problem with eutrophication in Sweden. Untreated, or partially treated, domestic sewage is a major source for discharge of phosphorus (P), which is the nutrient most frequently responsible for eutrophication of most fresh waters and the Baltic Sea. The waste water can be cleaned by filter materials, which have a high P-retention ability and which after saturation may be used as fertilizers. Four potentially suitable filter materials were tested in batch- and column experiments in this study. In the batch experiments, the following materials were shaken with waste water in time series ranging from 5 seconds to 60 minutes: coarse (1-4 mm) and fine (0-2 mm) Polonite® (heated bedrock from Poland); Filtralite® (light expanded clay aggregates with limestone added before burning); water cooled blast furnace slag (BF-slag) and BF-slag mixed with 10% burned limestone.

Extraterrestrisk och terrestrisk kromrik spinell i fanerozoiska kondenserade sediment

This study aims to assess the normal inflow of extraterrestrial chromite to Earth. The results from the investigationare compared to earlier studies of middle Ordovician Orthoceratite Limestone in which 1 - 3 extraterrestrial chromitegrains ( >63 ?Êm ) per kilogram limestone were found. These values have been interpreted as evidence of a twoorders of magnitude increase in the flux of extraterrestrial matter to Earth during a part of middle Ordovician.From an early Paleocene marine sedimentary sequence with known sedimentation rate in Zumaia, northernSpain, 90,5 kilogram of condensed limestone, dated to about 63 Ma, was sampled. The limestone was dissolved inhydrochloric- and hydrofluoric acid and the residue was sieved and searched for opaque minerals under the binocularmicroscope.

Miljöoptimera avfallsindustrin i Sverige : - återvinn restprodukten gips

One of the most common ways to produce heat and electricity in Europe today is by the incineration of waste or combustion of coal. These materials can be very sulfurous and during combustion sulfur dioxide is produced. This is an environmental and health related toxic substance which is why power plants have strict regulations on removing it from the flue gas. Sulfur dioxide is removed from the flue gas by adding a limestone reagent. The sulfur dioxide reacts with the limestone and the synthetic product obtained is ?Flue Gas Desulfurization gypsum?.

Utvärdering av kalkstens egenskaper med laboratorie- och fältmetoder.

A pavement construction designed to cope with the different type of traffic loads; it is exposed to and at the same time it can resist the effect of the climate. A road structure consists of sub- and superstructure which is divided by a boundary known as terrace. During the construction of unbound layers (base course and sub-base course) in the superstructure, it is always ensured that the material meet the requirements for bearing capacity and the degree of compaction. These parameters are controlled by various laboratory tests and control methods. To obtain increased knowledge of the material and improve the quality of the compaction in the field, it is necessary to perform laboratory tests in order to determine material properties.A base course material 0/ 32 mm limestone from Gotland (Hejdeby) was investigated in this study.

Nitrat i grundvattnet : Modellanalys av vattenflöde till Hörviks vattentäkt

A well, situated on Listerlandet in the western part of Blekinge in Sweden, has a very high content of nitrate. Water with a too high content of nitrate is hazardous to human health, in particular to small children. The area surrounding the well is mostly drained agricultural land with some larger farms for chicken and mink. The well takes its water from the bedrock and is deeper than most other wells affected by nitrate. The bedrock in the area is dominated by limestone with a relatively high flow of water.This thesis was performed in order to find the source of the nitrate.

Gabioner - Ett alternativ vid vägbanksbygge i lösa leror

The use of gabions means a reduced amount of filling material in the road section and a more narrow construction. Also the use of limestone cement columns can be reduced. All together this results in lower costs. The columns stand for about 55% of the total costs for the road. If gabions are used you can reduce the total costs with over 10%..

Ljusspridningsvariationer i finpapperstillverkning

The purpose of this Master's thesis is to find possible explanations of variation in light scattering in a fine paper. Samples were collected from each second tambour during a time period of two weeks from a paper machine at MoDo Paper, Husum. Two data sets, consisting of 20 and 95 observations, were selected for extensive analysises of tensile and structual properties. The data was evaluated with multivariate data techniques using the programs Simca and Extract. The results of PCA- and PLS- analysises pointed out 3 of 52 variables as important for the variations in light scattering.

Lyftanordning för kraftuttag

This thesis has been developed inassociation with Strängbetong AB, Sweden.A few years backCementa AB introduced a new type of cement on the Swedish market: Byggcement,which is a Portland Limestone Cement. This type of cement is better for theenvironment and cheaper than Rapid Hardening Cement which is used today at SträngbetongAB.Strängbetong AB isvery interested in a change of cement in the factory and wants to know what ittakes to make a transition from Rapid Hardening Cement to Byggcement.This final projectaims at investigating how the workability and strength development are affectedby a transition from the existing cement to Byggcement and how we can change theproperties of the concrete by adding different types of superplasticizers. Laboratory and factoryexperiments were made, to investigate the transition..

Optimering av betong med Byggcement (CEM II) till håldäcksproduktion

This thesis has been developed inassociation with Strängbetong AB, Sweden.A few years backCementa AB introduced a new type of cement on the Swedish market: Byggcement,which is a Portland Limestone Cement. This type of cement is better for theenvironment and cheaper than Rapid Hardening Cement which is used today at SträngbetongAB.Strängbetong AB isvery interested in a change of cement in the factory and wants to know what ittakes to make a transition from Rapid Hardening Cement to Byggcement.This final projectaims at investigating how the workability and strength development are affectedby a transition from the existing cement to Byggcement and how we can change theproperties of the concrete by adding different types of superplasticizers. Laboratory and factoryexperiments were made, to investigate the transition..

Från ståtlig befästning till vittrande världsarv : En jämförelse av byggnadstekniska metoder för sammanbindning av skalmurar

This is a final year project considering constructional techniques for joining cavity walls. The project is related to an ongoing scientific programme about the restoration of The City wall of Visby located on Gotland. The programme was set by Riksantikvarieämbetet as a reaction to a collapse of the outer masonry wall shell which took place in February 2012.The City wall of Visby is a medieval fortification built out of limestone during the 13th century. The wall is constructed as a cavity wall with two separate masonry shells connected to each other through an intermediate core. During the 14th century the wall was heightened which lead to a higher stress, especially in the outer wall face.

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