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563 Uppsatser om Pre-placed aggregate concrete - Sida 4 av 38

Dimensionering av betongkonstruktioner : En jämförande studie av BBK 04 och Eurokod 2 vid dimensionering av balkar och pelare

Today, we use BKR and BBK 04 when designing concrete structures inSweden, which will, in the near future, be replaced by Eurocode 2. When you are designing buildings, you will use Eurocode 2 Part 1-1 and with this new standard, some new rules and general rules will be necessary to adopt. To examine how BKR and BBK 04 tells apart from Eurocode 2 when designing concrete structures, one beam and one column with often common dimensions, is studied. The beam is designed with consideration of (considerate to) durability at bending moments, shear forces and control of cracking. The column is designed with consideration of durability at eccentric axial load and bending moments in cross section on account of (due to) geometric imperfections. BBK 04 has gone one step closer to Eurocode 2 than earlier editions and the things that are different, when calculating reinforcement, is how they use the partial factors.

Att bygga i trä eller lättbetong : en jämförelse mellan väggkonstruktioner

Hudiksvall Municipality will build a new preschool. The goal is that the pre-school should reflect the municipality's environmental goals and meet building regulations. The wall structures that are compared in the report is an insulated wooden frame and a frame of lightweight concrete blocks from H + HWall structures are compared within the areas of U-values, air tightness, thermal storage capacity, fire ratings, moisture, durability, emissions and environment. In these categories the two wall structures will be rated in a scale from 1 to 5 and then the categories are weighted against each other. The weighting is based on Hudiksvall Municipality's assessment of the categories importanse for their final selection.The results of the comparison show that the concrete structure is recommended for the construction of pre-school with 27.55 points against the wooden structures 23.70 points.

Radon i betongkonstruktioner : - Kan det undvikas?

The following article consists of two parts; one part is about house construction and the other is a specialization about radon. The house construction part describes how to project a house from start. It contains the conformation of the house, the installations needed, calculations considering the strength of the construction, energy calculation and what materials were chosen. Calculations considering the costs of building and operate the house has been carried out. The result showed that the house would cost approximately two million Swedish kroner to build and thirteen thousand kronor a year to operate.

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.

REDOGÖRELSE FÖR SPRICKARMERING FÖR KONSEKVENT DRAGNA BETONGPLATTOR PÅ MARK : Analys av skillnader mellan BBK 04 och Eurokod 2 med tillämpning av svenskt och danskt nationellt annex

In this diploma work the approach of determining the required amount of reinforcement in slabs exposed to pure tension is processed, on behalf of Ramböll Uppsala. It is a well-known problem in the industry that there are uncertainties in the determining of the amount of crack reinforcement, especially for structures exposed to pure tension. Cracking caused during the time of dehydration in concrete slabs is the most common defect according to statistics made by CBI[1], which provides numbers as high as 35 % of all the defects caused on slabs are generated by cracks. Comparisons between Sweden's former national standard BBK 04, Building Regulations for concrete structures due to restrained forces of shrinkage, and the current European standard Eurocode 2 are carried out through theoretical studies and concludes with several examples of calculations. Rigorous calculations of both standards, BBK 04 and Eurocode 2 with application of the national annex in Sweden and Denmark are performed.

Hur påverkar gummigolv i grisningsboxen suggans liggtider, liggbeteende och hennes tid för att lägga sig?

In the farrowing pens the amount of bedding material and the quality of the concrete floor has a huge impact on both the sow and the piglets. In this study imbedding of rubber flooring on the solid area in the farrowing pen was used to see if it had any effects on the sows lying behaviour when compared to concrete. Another important aspect was to evaluate if the rubber floorings had a high enough durability to resist the normal wear in a farrowing pen. Concrete flooring is assumed to have a higher thermally conductive effect then rubber which can affect the sow?s chance to cool down.

Stommaterial för villor - trä eller betong?

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.

"Ibland tror jag man kan ha en dubbelmoral inom sig själv..." : - En studie om gymnasielevers förståelse av jämlikhet på en principiell och konkret nivå

The purpose of this study is, by groupinterviewing students in upper secondary school, to investigate students comprehension of equality on a principle level and a concrete level. The questions at issue are as follows; how is the comprehension on respective levels described and is there any difference or similarities between the two levels? Further more, this study also aims to end with a discussion regarding the result from the mainpurpose in relation to the educational environment. In my conclusion there is to be find a certain difference between the comprehensions of equality on the two levels. The conception of equality is in the beginning principled and there is no exception from the worth of every individual but however, when the conception is brought out in reality it gets depended of its context and the comprehension for equality becomes more dynamic. The project will be completed with a discussion regarding the results in relation to the educational environment. .

Manusutveckling av digitala läromedelsapplikationer i matematik : En studie av samtida pedagogisk forskning och utveckling av applikationsmanus för matematikämnet i gymnasieskolan

In a world where digital media is becoming a greater part of people?s everyday and working lives it is plausible to assume that the upcoming generation of pupils expect the teaching media to adapt thereafter. It is this assumption of an increased demand that Natur & Kultur is hoping to be able to meet. This thesis has been a stage in the process of producing digital material in the subject of mathematics for high school students. Specifically the aims of this thesis have been to make a rough description of the largest competitive companies? products within the same market, explore and put together a brief theoretical foundation of contemporary research and produce concrete examples of ideas for digital applications.

Hållbarhetscertifiering av stadsdelar : En studie av BREEAM Communities praktiska tillämpning i svensk stadsbyggnad

In this diploma work the approach of determining the required amount of reinforcement in slabs exposed to pure tension is processed, on behalf of Ramböll Uppsala. It is a well-known problem in the industry that there are uncertainties in the determining of the amount of crack reinforcement, especially for structures exposed to pure tension. Cracking caused during the time of dehydration in concrete slabs is the most common defect according to statistics made by CBI[1], which provides numbers as high as 35 % of all the defects caused on slabs are generated by cracks. Comparisons between Sweden's former national standard BBK 04, Building Regulations for concrete structures due to restrained forces of shrinkage, and the current European standard Eurocode 2 are carried out through theoretical studies and concludes with several examples of calculations. Rigorous calculations of both standards, BBK 04 and Eurocode 2 with application of the national annex in Sweden and Denmark are performed.

Spetsbärförmåga hos betongpålar slagna i friktionsjord

The purpose of this study was to build a database for point-bearing piles in dense noncohesive soil, predominantly moraine. Further, the database was analysed and areas with difficult geotechnical conditions was identified.The database includes for point-bearing piles driven to refusal in moraine. Piles with mainly shaft friction have been excluded. Only concrete piles have been included. Geographically the database covers almost all geotechnical conditions of Sweden.

Axial- och gradientkrympning hos golv på mark enligt Eurokod 2 : Sprickbredders beroende av betongkvalité, tvångseffekter och armeringshalt

AbstractConcrete foundation slabs are usually exposed to unilateral drying during the curing process. The unilateral drying causes an axial shrinkage and a concave curvature of the construction. The curvature results from the fact that the upper part of the slab is drying and shrinking faster than the lower part. This is called gradient shrinkage.A problem occurs when the slab is considered fully restrained by adjoining structural parts. The deformations caused by axial contraction due to the constant part of the shrinkage and the curvature caused by gradient shrinkage of the slab are then prevented by the fact that the slab is fully restrained.

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. .

Förbättring av U-värde i träkonstruktion för fönster med Aerogel

When constructing a building, a number of aspects must be harmonized in order for it to fulfill requirements ? a building must fulfill requirements such a load-bearing, conservation of energy and a good indoor environment by means of, among other things, moisture proofing .Moisture problems in buildings can affect health negatively. As we are increasingly staying in indoors, demands on a good indoor environment are higher.This work starts with examining moisture problems in slab-on-ground solutions, and then links the various scenarios to moisture problems in a concrete slab of a real building. The building with moisture problems is located in Årby by in Borlänge and moisture damage was found in the slab at an apartment adjoining wall.By reviewing literature written within the field of moisture problem, making hand calculations and modeling in the program Comsol Multiphysics, judgments are made to find explanations as to why the rise of moisture occurred in the building in Årby by.Generally, the following guidelines may be used to reduce the risk of moisture problems in slab-on-ground constructions:Drying of construction moisture before laying the floor material.Using draining layer beneath the slab, to prevent capillary suction.Using insulation under the slab, partly for comfort and to establish the temperature difference between the ground and the concrete slab.Avoid direct contact between the wood and concrete, due to degradation and fouling smells that normally occurs.If necessary, use additional vapor barrier.In addition to the above, there are various methods for moisture-proof and moisture-monitoring by design or by the method ByggaF suited for the entire construction process various events..

Development of concrete compressive strength: a study of Swedish bridges constructed during the 20th century

Tryckhållfasthetsutveckling hos broar. En studie av svenska broar byggda under 1900-talet.

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