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1980 Uppsatser om Construction moisture - Sida 2 av 132

Fuktskador i ytterväggar på grund av vattenintrång

Moisture damage in buildings is a serious issue that leads to problematic consequences and high economic costs. Despite the knowledge and awareness existing about moisture problems, extensive damager still occurs today. Studies of moisture in the exterior wall constructions shows that the issue if often caused by rain and water intrusion. These kinds of problem result in major costs usually because the companies have to replace the material and structural components and also in some cases tear down large parts of the buildings.The work includes moisture theory and descriptions of four different exterior wall constructions, wood stud wall with plastered facade, exterior wall with wood facade, exterior wall with concrete, and exterior wall with brick facade. Our thesis work describes how the constructions are affected and moisture damage due to water intrusion.

Påverkande faktorer för grotens fukthalt

The aim of this study was to investigate how seasonal variations affect the quality of logging residues. The study was hosted by VIDA Energy. Logging residues can be processed and transported within different systems. Today the dominant systems are chipping at landing and bulk transportation of logging residues. In these systems the handling of the logging residues are carried out in the same manner up to the landings. Moisture content at the time of chipping is the primary quality parameter. Fine fractions of logging residues are strongly dependent on moisture content in storage.

Fukt i byggnadsmaterial : Hur man förebygger fuktskador vid materialhantering på byggarbetsplatsen

Byggsektorn har fortfarande svårigheter med att hantera fuktproblematiken.  Vi har valt att fokusera på hanteringen av material i produktion. Den informationssamling vi utfört ligger till grund för vår analys och slutsats. Vi har intervjuat flera olika entreprenörer från byggbranschen för att ge oss en helhetssyn av fuktsäkerheten ute på byggarbetsplatserna. Studien påvisar att det råder brister både på beställar- och entreprenörssidan. Vi ser att det finns potential för förbättring när det så krävs.

Fukthalt i GROT - påverkande faktorer :

This study was carried out at the request of the bio energy company Naturbränsle. The company handles annually 750 000 m3 of chips from logging residues from a large area, from Östergötland in the south to Härjedalen in the north. In that area, about 50 bio fuel plants are customers. When Naturbränsle deliver chips from logging residues to their customers, the moisture content varies from 30 % to 60 %. The aim of the study was to sort out the affecting factors on the moisture content in the chips during handling and storage processes.

Återfjädring vid bockning av höghållfast stål

Svenska Aerogel AB has developed the material Quartzene® which is of the typeprecipitated silica and contains calcium - magnesium silicate ((Ca, Mg) SiO3). Thematerial is used for molecular filtration of contaminated air. Qartzene?, which is inpellet form, is porous and has a high internal surface which is a requirement for themolecular filtration. With the use of various impregnations, filtration can affect thedesired outcome.

Fuktegenskaper hos Quartzene impregnerat med salter

Svenska Aerogel AB has developed the material Quartzene® which is of the typeprecipitated silica and contains calcium - magnesium silicate ((Ca, Mg) SiO3). Thematerial is used for molecular filtration of contaminated air. Qartzene?, which is inpellet form, is porous and has a high internal surface which is a requirement for themolecular filtration. With the use of various impregnations, filtration can affect thedesired outcome.

Effektiv lagerstyrning genom tillförlitlig prognostisering : Effective inventory control through reliable forecasting

This study was done regarding whether sealing or ventilation is the best solution to prevent moisture on cold attics. The authors of this report addressed the problem with moisture in attics when they started their cooperation with Peab.The methods included interviews with people, database research, and calculations of a project in Akersberga north of Stockholm. The conclusion is based on interviews and other information as they are analyzed in relation to the house of reference. The focus of this report is on problems with moisture in the attics known as cold attics.The background of the problem with moisture is that today?s slabs are usually insulated to save energy and that the attics nearly gives the climate as the outdoor climate.

Tätning eller ventilering mot fukt på kalla vindsutrymmen

This study was done regarding whether sealing or ventilation is the best solution to prevent moisture on cold attics. The authors of this report addressed the problem with moisture in attics when they started their cooperation with Peab.The methods included interviews with people, database research, and calculations of a project in Akersberga north of Stockholm. The conclusion is based on interviews and other information as they are analyzed in relation to the house of reference. The focus of this report is on problems with moisture in the attics known as cold attics.The background of the problem with moisture is that today?s slabs are usually insulated to save energy and that the attics nearly gives the climate as the outdoor climate.

EAS-tagg med fuktsensor : Design och utvärdering av EAS-alarmteknologi för fuktdetektering

Electronic article surveillance (EAS) is widely used in shops and libraries together with an RF-tag attached to the goods or books in order to prevent shoplifting. By implementing the addition of a moisture sensor to the RF-tag, other functions become possible, including the ability to use as an alarm with regards to frozen goods, which have been shipped but which have melted and have, subsequently, refrozen. In- relation to care for the elderly, one time-consuming step involves checking whether there is the necessity for a change of diaper and this can, instead, be based on an RF-tag with an EAS-system alarm. A preliminary investigation was made using the moisture sensors, which involved how the resistance changes when liquid and/or heat is applied. A simulation of the LCCR circuit (RF-tag with the sensor) was conducted in order to determine how the resonance frequency changes for different resistances levels.

Droppbevattningens inverkan på kvalitet och kvantitet hos Solanum tuberosum L i jämförelse med konventionell spridarebevattning :

A literature study and a field trial have been carried out in order to investigate the physiological response of potato plants to different soil moisture levels. Higher yield, quality and number of tubers can according to the literature be obtained if constant high soil moisture is kept during major parts of the growing season. A field trial was set up where drip irrigation was used as an alternative to conventional irrigation techniques to maintain high and constant soil moisture. The application of water in the drip irrigated area was monitored and adjusted on a daily basis so that the soil moisture stayed as close as possible to the recommended level. The sprinkle irrigated area was irrigated according to traditional practices with approximately 35 mm every 7th to 10th day depending on the whether.

Utvärdering av befintliga passivhus : En byggnadsfysikalisk bedömning och mätningar om temperatur, och fukt analys på ytterväggarna

Energy price are on the way up to a high level that will not diminish in the future make us to focus more on the sustainable development for a better solution of residential houses. Passive house or low energy housing are one of the solution to make residential more environment friendly, in same time it´s a financial security using less energy, and saving money. The last 10 years in Germany and all around Europe the concept of passive house been developed, and people aim to know more about these concept that leading the market more attractive for passive houses. A passive house is a well designed building highly insulated and air tight with mechanical ventilated system for the whole building envelope that minimizes the use of energy for heating [1].The housing company Mimer has chosen to invest in low energy consumption in every new housing project.  These future plan projects are decided to use less than 75 kwh per square meter annually in purchased energy [2].This thesis is about new constructed passive houses, and focuses on the evaluations of the temperature, and moisture condition for attic, external walls and joist.

Elementkoncentrationer i gran utmed en markfuktighetsgradient :

One key factor in silviculture today is sustainability. In order to achieve sustainability it may be important to restore lost nutrients to the forest after clearcutting. In order to calculate the removal, you need to know how much of different elements you will find in different tree compartments. The aim of this study was to investigate if the concentration of elements in different tree compartments of spruce (Picea abies (L.) Karst) were related to the moisture conditions of the site. Five plots at Risfallet (60º 21´ N, 16º 13´ E), was placed along a moisture gradient in a 40- year spruce stand.

Energihushållning och varsamhet för äldre byggnader : Chefsbostaden i Strömsholm, ett timmerhus från 1900-talets början

This report is the result of a degree project in building engineering, at an advanced level. The project evaluated a building from a technical and historical point of view, and focused on its energy consumption, particularly the energy used for heating. The building in question was a small apartment building in Strömsholm, Sweden. It was made in 1902, from vertical logs, a not so common form of the traditional log house. The goal of the project was to evaluate if the energy consumption could be reduced in accordance with building preservation regulations, that is without damaging any of the building?s cultural or historical values.The building was surveyed with the help of archive and literature studies, interviews and inspections.

Hårdgörning av Asp

Hårdgörning av trä syftar till att göra materialet hårdare. Detta går att åstadkomma genom komprimering, det komprimerade materialet tenderar dock att återgå mot sin ursprungsform då materialet utsätts för fukt om ingen låsning sker. Låsningen kan ske mekaniskt i en treskiktskonstruktion som motverkar träets fuktrörelser. Dessa skivor har dock visat sig vara instabila och tidigare försök har uppvisat deformationer i form av kupning. Denna undersökning syftar till att utreda förutsättningarna för att använda komprimerad asp samt att ta fram underlag för framtagning av en kommersiell produkt.Praktiska tester har genomförts för att studera hårdhet, återfjädring och densitet hos det komprimerade virket.

Automatisering av spraytorkningsprocess

ABB Surge Arrestors in Ludvika have for a long time had a problem to keep the moisture at a steady state in the production of their ZnO-powder, that is used to produce varistors.Some black-box models of the spray drying process have been designed and evaluated to find a solution for the problem. After evaluating the collected data it has been found that variations in the supply voltage causes control difficulties for the operator. A cascade control system was designed, consisting of three PI control loops designed with lambda tuning. The disturbance in the supply voltagewas used as a feed forward in the control system.At the end of the project the control system was installed, and tests were made to verify the functionality of the regulator. It was shown that most of the variations in the moisture of the powder could be eliminated using small resources, through purchase of a process controller and four power meters.

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