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2308 Uppsatser om Concrete construction - Sida 2 av 154

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.

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.

Utfackningsvägg i fältfabrik : en studie av arbetsmiljö och enhetstider

Construction companies are frequently criticized for high prices and long construction time. At the same time, statistics shows that construction workers are on the sick-list for occupational injuries or casualties more than other groups at the labour market.Skanska built a block of flats with tenant-ownerships in Gävle. The construction consists of concrete walls with in-fill walls in the front. The purpose with this degree project is to perform a risk analysis in work environment with focus on repetitive strain injuries and control the time report for in-fill walls manufactured in a field factory. The result of this project will help to make more realistic cost predictions in the future.This degree project has been performed in cooperation with the construction company Skanska.

Utvärdering av den bärande tegel- och betongstommen i en byggnad från år 1916

This Master thesis is about a postal- and telegraphic building in Eskilstuna, Sweden. The construction methods for the specific building and buildings in general from the same time are described. The purpose of the report is to describe the loads acting on the building and how it has been built and why it has been rebuilt during the years. After this, possibilities of reconstruction and adaptation for today?s demands can be evaluated.

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..

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..

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.

Fuktproblematik i platta på mark : En analys av uppkomsten till fuktproblem

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..

BIM Building Information Model : Hinder & Drivkraft

The  construction  industry  is  a  costly  business  such  in  respect  of  capital  for  most construction defects which then require rework, tear down and rebuild again. This study is  meaningful  awareness  of  tools  that  can  reduce  this  best  through  communication  and information sharing between the parties.  The  construction  industry  is  known  as  temporary  projects  organizations,  where  the construction  project  consists  of  several  actors  who  have  to  communicate  and  share information  between  them  to  avoid  mistakes  later  in  the  build  time.  These  actors  are bounded together thus for the duration of the project, then broken when the project has reached its end. The challenge here is for these actors to apply a tool that can help and simplify communications, information sharing, and perhaps the most important aspect is to  create  a  routine  for  the  association  and  the  shattering  of  these  actors.  To  implement such  behavior  using  a  tool  such  as  BIM  in  the  industry  whose  size  perhaps  is indescribable may be a very hard task.  BIM (Building Information Model) could be seen as the solution to this problem because it  acts  as  a  portal  where  the  actors  involved  must  sign  in  and  communicate,  share information, and eventually create a behavior, a routine for this association and division of  the  actors  following  the  end  of  the  project.  The  technology  could  help  the  involved from  the  beginning  of  the  project,  already  in  the  model  stage,  break  down  and  prevent any construction barriers when the building has been placed in the works.

Prefabricerade passivhusväggar

Background: The most energy efficient houses today are so called passive houses. These houses achieve high energy-efficiency partly by having well insulated walls. U-value describes the amount of heat transfered through a building element, the more insulation, the smaller U-value. A typical passive house wall have a U-value of 0.10 W/m2,°C. The passive houses are primarily made as small family houses and not as a block of apartments.

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.

Miljöval för byggnadsmaterial : Med häktet i Helsingborg som referensobjekt

Today's climate and environmental issues have now been up for discussion for quite long. Various environmental measures have been taken, but it is not always certain that those measures actually are for the better because of the complexity of our environment. Therefore, studies of whole life cycles are very important even if they are time and resource intensive.Real estate accounts for 15% of global carbon emissions, but also affects our environment in many other aspects. In Sweden this number is even higher. About 30 % of its carbon dioxide emissions originates from building sector and changes are therefore of great importance.

Kartläggning av en fastighets miljöpåverkan : Livscykelanalys av flerfamiljsfastigheten "Teodoliten"

Today's climate and environmental issues have now been up for discussion for quite long. Various environmental measures have been taken, but it is not always certain that those measures actually are for the better because of the complexity of our environment. Therefore, studies of whole life cycles are very important even if they are time and resource intensive.Real estate accounts for 15% of global carbon emissions, but also affects our environment in many other aspects. In Sweden this number is even higher. About 30 % of its carbon dioxide emissions originates from building sector and changes are therefore of great importance.

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.

Tid- och kostnadsanalys av innerväggar

In our thesis we will compare interior walls, both bearing and non-bearing. All of thewalls analyzed are currently used in production by Skanska Construction, who is alsoour employer/supervisor for the project. The different wall types will be comparedfocusing mainly on time, cost and workability. All of these walls aside from the nonbearingwall are constructed using concrete, either prefabricated or cast on site..

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