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Miljöbelastning vid förtida utbyte av enstegstätad putsfasad : Orsakad av fuktskador / Environmental impact caused by reconstruction of unventilated plaster walls : Caused by moisture damageSundström, Olle, Sundström, David January 2012 (has links)
När en konstruktion blir fuktskadad påverkas de ingående materialen på olika sätt och i vissa fall uppstår så kallad mikrobiell tillväxt som kan påverka människans hälsa. Det finns studier om hur människor reagerar på sådan mikrobiell tillväxt, hur materialen påverkas av olika fuktbelastningar och hur mycket pengar det kostar att byta ut denna konstruktion. Vad som inte finns är hur miljön påverkas att i förtid behöva byta ut en fuktskadad konstruktion. Utifrån ovan nämnda har detta examensarbete vid högskoleingenjörsprogrammet i Byggteknik och design vid Kungliga Tekniska Högskolan utförts. Det har utförts tillsammans med AK-konsult Indoor Air AB och har i uppdrag att belysa vikten i att fuktsäkerhetsprojektera rätt utifrån ett miljöperspektiv, och att få faktiska siffror på hur mycket koldioxid det genererar att i förtid behöva byta ut en konstruktion. Rapporten är avgränsad till en putsad enstegstätad regelvägg som är uppbyggd enligt följande: utvändig puts, putsbärare av EPS, vindskyddsskiva, träreglar med mellanliggande värmeisolering, luft- och ångspärr och invändig skiva. Miljöpåverkan har beräknats i hur mycket koldioxid 1 m2 av denna konstruktion genererar. Koldioxidutsläppen för de ingående materialen har i största möjliga mån beaktats och beräknats utifrån råvaruutvinning, transport av råmaterial, tillverkning av produkter och transport fram till byggarbetsplatsen. För att kunna beräkna transporter av material och arbetskraft för uppförandet av konstruktionen har en fiktiv byggarbetsplats bestämts (Hammarby Sjöstad, Stockholm). Även för att ge en bättre bild om hur stora koldioxidutsläppen är vid transport av material och hur ett verkligt fall kan se ut har en fiktiv väggyta på 198 m2 valts att studeras. De emissionsvärden som använts i denna rapport baseras i första hand på de olika materialtillverkarnas byggvarudeklarationer samt samtal med miljöansvariga på de berörda företagen. För att lättare kunna jämföra resultaten av de ingående materialen i detta examensarbete presenteras de i form av utsläpp av totalt kilo koldioxid per mängd material [kgCO2/mängd material]. Det presenteras även fyra olika uppbyggnader av den putsade enstegstätade regelväggen. Det för att visa hur miljön påverkas om tjockputs eller tunnputs används tillsammans med glasfiberarmerad vindskyddsskiva eller en pappbeklädd vindskyddsskiva med en kärna av gips. Dessa olika typer av väggkonstruktionerna betecknas vägg 1, 2, 3 och 4 i rapporten. De resultat som tagits fram visar att det genereras ungefär lika mycket koldioxid att byta ut 198 m2 av den angivna väggkonstruktionen som att köra en bensindriven personbil nästan ett halvt varv runt jorden (jordens omkrets är ca 4000 mil). Resultaten visar att det är små skillnader i koldioxidutsläpp vad det gäller de olika väggkonstruktionerna. Vägg 2 genererar den största mängden koldioxid, totalt 3223 kgCO2 (1 m2 genererar 16 kgCO2), följt av vägg 1 som genererar 3206 kgCO2 (1 m2 genererar 16 kgCO2). Resultaten visar att produktion av material står för den största individuella delen av utsläpp, 2181 kg koldioxid (ca 2/3 av de totala koldioxidutsläppen) för vägg 2. Där bidrar glasullen med den ingående största delen 891 kgCO2 (41 % av det totala koldioxidutsläppet från materialtillverkning), följt av armeringsnätet på 364 kgCO2 (17 % av det totala koldioxidutsläppet från materialtillverkning). Materialtransporter står för ungefär 505 kg koldioxid (ca 1/6 av de totala koldioxidutsläppen) och styrs främst av typ av lastbil, avverkad sträcka samt lastutnyttjande. Persontransporter till och från arbetsplatsen står för ungefär 537 kg koldioxid (ca 1/6 av de totala koldioxidutsläppen) där mängden koldioxid främst styrs av antalet arbetade dagar samt typ av transportfordon. Den genererade mängden koldioxid för ett totalt utbyte av en väggkonstruktion på 198 m2 skulle, omräknat i svensk elmix, förbruka en energimängd som skulle räcka till byggnadens specifika energianvändning i 17,9 år. Ca 36 % av byggnadens förväntade livslängd på 50 år. Resultaten i denna rapport visar att det ur ett miljöperspektiv är viktigt att lägga stor vikt vid fuktsäkerhetsprojektering. Detta för att påverkan på miljön kan begränsas avsevärt om konstruktioner inte behöver bytas ut i förtid pga. omfattande fuktskador. Med tanke på hur många kvadratmeter dylik fasad som byggts finns högst sannolikt en tämligen stor miljöskuld inbyggd i denna fasadtyp. / When a structure is damaged by moisture, the materials are affected in different ways and sometimes this moisture will lead to mould growth that can affect the human health. Today we can read studies about how human health reacts to this mould growth, how materials reacts and how much money it costs to rebuild the moisture damaged structure. What we don´t know is how much impact it will have on the environment to replace a moisture damaged structure with a new one. From these initial sentences is this degree project in building technology, first level at the Constructional engineering and design program at Kungliga Tekniska Högskolan. This thesis is commissioned by AK-konsult Indoor Air AB and is supposed to highlight the importance of protecting structures against moisture damage from an environmental point of view. Furthermore it will also result in real figures over how much carbon dioxide a premature replacement will generate. This thesis will strictly look at an insulated, rendered, unventilated and undrained stud wall. It is build-up as: exterior plaster, plaster base (EPS), wind protect-board, wooden framework with insulation, polyeten sheet and interior board. The environmental impact will be measured in how much carbon dioxide 1 m2 of this wall construction will generate. Carbon dioxide emissions from wall materials have been calculated on the basis of resource extraction, transportation of raw materials, manufacturing of products and transportation to construction site. To make the transportation calculations possible a fictitious construction site has been determined (Hammarby Sjöstad, Stockholm). Also to provide a better picture of how big the emissions are from transportations and how a real case scenario can look like have a 198 m2 wall been calculated. The carbon dioxide emissions in this report are in first hand based on material manufacturer’s environmental declarations and dialogues with environmental specialists at manufacturers. To make the comparison of the result easier between the construction materials they all will be presented in terms of kilo carbon dioxide [kgCO2/amount material]. The result will also present four different types of the above named wall construction. That is to show how the environment affects if thick or thin plaster is used together with fiberglass reinforced wind protect-board or papercoated wind protect-board with gypsum core. These different types of wall construction will in the report be named as wall 1, 2, 3 and 4. The result from this report show that it is generating approximately the same amount of carbon dioxide to change the moisture damage wall as to drive a gasoline-powered car halfway around the earth (diameter approximately 4 0000 kilometers). The results show that it is small differences in carbon dioxide between the four types of wall constructions. Wall 2 generates the largest amount of carbon dioxide emissions, total 3223 kilo (1 m2 generates 16 kgCO2), followed by wall 1 that generates 3206 kilo carbon dioxide (1 m2 generates 16 kgCO2). The result also shows that the largest amount of emissions is created by the production of the new materials, 2181 kilo carbon dioxide (approximately 2/3 of the total carbon dioxide emissions). Where the largest amount of emissions comes from glass wool with 891 kilo carbon dioxide (41 % of the total carbon dioxide from the material production), followed by reinforcement mesh with 364 kilo carbon dioxide (17 % of the total carbon dioxide emissions from material production). Transportation of materials stands for 505 kilo carbon dioxide, slightly less than 1/6 of the total, with key parameters distance, type of vehicle and load utilization. Transportation of labor stands for approximately 537 kilo carbon dioxide slightly more than 1/6 of the total carbon dioxide emissions where the key parameters are number of worked days and type of transportation. The generated carbon dioxide emissions to build a new 198 square meter wall construction corresponds to the specific energy use for a normal house (198m2) for over 17,9 years. Approximately 36 % of the buildings expected life-span of 50 years. The result shows that it is important from an environmental point of view to protect constructions from moisture damage. That is because the fact of not needing to premature replace the moisture damaged construction can considerably reduce the environmental impact. Considering how many such facades that are built is it most likely a rather large environmental liability built in this facade type.
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Rapid estimation of lives of deficient superpave mixes and laboratory-based accelerated mix testing modelsManandhar, Chandra Bahadur January 1900 (has links)
Doctor of Philosophy / Department of Civil Engineering / Mustaque Hossain / The engineers from the Kansas Department of Transportation (KDOT) often have to decide whether or not to accept non-conforming Superpave mixtures during construction. The first part of this study focused on estimating lives of deficient Superpave pavements incorporating nonconforming Superpave mixtures. These criteria were based on the Hamburg Wheel-Tracking Device (HWTD) test results and analysis. The second part of this study focused on developing accelerated mix testing models to considerably reduce test duration.
To accomplish the first objective, nine fine-graded Superpave mixes of 12.5-mm nominal maximum aggregate size (NMAS) with asphalt grade PG 64-22 from six administrative districts of KDOT were selected. Specimens were prepared at three different target air void levels @ N[subscript]design gyrations and four target simulated in-place density levels with the Superpave gyratory compactor. Average number of wheel passes to 20-mm rut depth, creep slope, stripping slope, and stripping inflection point in HWTD tests were recorded and then used in the statistical analysis. Results showed that, in general, higher simulated in-place density up to a certain limit of 91% to 93%, results in a higher number of wheel passes until 20-mm rut depth in HWTD tests. A Superpave mixture with very low air voids @ N[subscript]design (2%) level performed very poorly in the HWTD test.
HWTD tests were also performed on six 12.5-mm NMAS mixtures with air voids @ N[subscript]design of 4% for six projects, simulated in-place density of 93%, two temperature levels and five load levels with binder grades of PG 64-22, PG 64-28, and PG 70-22.
Field cores of 150-mm in diameter from three projects in three KDOT districts with 12.5-mm NMAS and asphalt grade of PG 64-22 were also obtained and tested in HWTD for model evaluation. HWTD test results indicated as expected. Statistical analysis was performed and accelerated mix testing models were developed to determine the effect of increased temperature and load on the duration of the HWTD test. Good consistency between predicted and observed test results was obtained when higher temperature and standard load level were used. Test duration of the HWTD can thus be reduced to two hours or less using accelerated mix testing (statistical) models.
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A Study of Moisture Induced Material Loss of Hot Mix Asphalt (HMA)Arepalli, Uma Maheswar 04 December 2017 (has links)
"Susceptibility of Hot Mix Asphalt (HMA) mixes to moisture induced damage is one of the main reasons for premature failures of asphalt pavements. Hence, the evaluation of mixes for the moisture susceptibility is an essential part of the mix design. The existing methods are found to be in-sufficient to characterize mixes in terms of their moisture damage potential, and many studies have been conducted to establish an improved methodology that can better address the issue. Most of these methods involve the determination of changes in mix properties due to moisture conditioning in the laboratory or to verify the mix performance in the field or the laboratory. In the field moisture susceptible mixes are also found to lose material to extents that are dependent upon the properties of the mix and materials. So far, there has been no comprehensive study to investigate the loss of materials due to moisture induced damage. The objective of this study was to identify and evaluate a conditioning and a test method that can be used on a regular basis to detect moisture susceptible mixes and to understand the combined problem of moisture induced material loss and change in strength/stiffness of the mix. The Moisture Induced Stress Tester (MIST), Ultrasonic Pulse Velocity (UPV), Dynamic Modulus in Indirect tensile mode, and Indirect Tensile Strength (ITS) tests were utilized in the study. The effluent from the MIST was checked for the gradation of dislodged aggregates and the Dissolved Organic Carbon (DOC) content. A system dynamics (SD) approach was also adopted to investigate the problem and establish a model to reproduce field observations. The results showed that the use of MIST in combination with UPV or ITS is able to identify moisture susceptible mixes, in particular for mixes with the potential of aggregate breakdown. The mixes with a higher loss of asphalt binder during conditioning exhibit higher tensile strengths, and those with a loss of finer materials, which is indicative of aggregate breakdown, show a lower tensile strength. For the mixes used in this study, the rate of change in indirect tensile strength during moisture conditioning was found to be strongly correlated to the pre-conditioning modulus of the mix. A step-by-step framework to characterize the moisture susceptible mixes was presented."
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Influence of fundamental material properties and air void structure on moisture damage of asphalt mixesArambula Mercado, Edith 15 May 2009 (has links)
Moisture damage in asphalt mixes refers to the loss of serviceability due to the presence of
moisture. The extent of moisture damage, also called moisture susceptibility, depends on internal
and external factors. The internal factors relate to the properties of the materials and the
microstructure distribution, while the external factors include the environmental conditions,
production and construction practices, pavement design, and traffic level.
The majority of the research on moisture damage is based on the hypothesis that
infiltration of surface water is the main source of moisture. Of the two other principal
mechanisms of water transport, permeation of water vapor and capillary rise of subsurface water,
the latter has been least explored. A laboratory test and analysis methods based on X-ray
computed tomography (CT) were established to assess the capillary rise of water. The amount
and size of air voids filled with water were used in the capillary rise equation to estimate the
distribution of the contact angles between the water and the mastic. The results were able to
show the influence of air void size on capillary rise and contact angles.
The relationship between air void structure and moisture susceptibility was evaluated
using a fundamental fracture model based on dissipated energy of viscoelastic materials.
Detailed description is provided in this dissertation on the deduction of the model equation, the
selection of the model parameters, and the required testing protocols. The model parameters
were obtained using mechanical tests and surface energy measurements. The microstructure of
asphalt mixes prepared in the laboratory having different air void structures was captured using
X-ray CT, and image analysis techniques were used to quantify the air void structure and air
void connectivity. The air void structure was found to influence the mix resistance to moisture
damage. To validate the fracture model, asphalt mixes with known field performance were tested.
The results demonstrated that the fracture model is an effective tool to characterize moisture
susceptibility. In addition, the model showed good correlation with the reported field
performance of the asphalt mixes.
The findings of this study will be useful to highway engineers to evaluate asphalt mixes
with alternative mix designs and internal air void structures and to estimate the rate of moisture
infiltration in order to maximize the resistance of asphalt mixes to moisture damage.
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Fukt i byggnadsmaterial : Hur man förebygger fuktskador vid materialhantering på byggarbetsplatsen / Moisture in building materials : How to prevent moisture damage during material handling at the construction siteNyman, Peter, Geuriya, Tomas January 2012 (has links)
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. Därför rekommenderar vi att högre krav ställs på fuktsäkerheten och att tydliga riktlinjer finns att följa. Den handbok som framtagits är riktat till att hjälpa yrkesarbetarna på entreprenörssidan att uppnå de krav som ställs. Handboken innehåller tillvägagångssätt för materialhantering och fuktkvotsmätning samt kritiska fuktvärden för olika material. / The construction sector still has difficulties in dealing with moisture problems. We have chosen to focus on the material handling in the production phase at the building site. The information collection we performed is the basis for our analysis and conclusion. We have interviewed several contractors in the construction industry to give us a comprehensive view of the moisture safety out on construction sites. The study shows that there are shortcomings on both constructor- and contractor’s side. We see that there is a potential for improvement when it’s required. We recommend that greater demands are placed on the moisture safety and that clear guidelines are to follow. The handbook is directed at helping skilled workers in the contractor end to achieve the required demands. The handbook includes procedures for material handling and moisture measurements as well as critical moisture values for different materials.
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TAKTERRASSER PÅ FLERBOSTADSHUS : En analys av takterrasser relaterat till dess projektering, utförande och fuktproblem de kan medföraLundqvist, Oscar January 2021 (has links)
Roof terraces are in great demand today and can add value to the home. Theirdesign can vary but often they can also contribute and increase the risk of moisture in the building and cause problems. This is because they are flat and often have doors that lead out to a terrace where water can collect. The purpose of the study is to examine how roof terraces are designed and executedwith a goal of finding designs that should be avoided and designs that can be recommended.This will be done by reviewing previously designed roof terrace projects, literature studies,interviews with people with significant experience in the subject and highlighting relevantexperiences from my previous professional experiences as a carpenter. In the study, critical areas and processes during the design as well as the production of a roofterrace will be highlighted and explained why they are critical. The advantages of asuperstructure consisting of a wooden deck will be highlighted. The importance of the rightskills at the right time will also be discussed. The results of the work will highlight the importance of a solid design of waterproofing layerson roof terraces and why implementation of waterproofing layers may be relevant. It will alsosummarize what you should think about in order to design blueprints that meet the right conditions for a high quality and improved execution. / Takterrasser på flerbostadshus är idag väldigt efterfrågat och kan ha ett stort mervärde till en bostad. De kan utformas varierat men gemensamt för dem att de bidrar till en ökad risk för fuktproblematik i byggnaden. Detta då de är nästintill platta och dessutom ofta har dörrar ut till terrassen i höjd med där vatten samlas.Studiens syfte är att granska hur takterrasser projekteras samt utförs av idag med ett mål om att finna utföranden som bör undvikas och utföranden som kan rekommenderas. Detta har gjorts genom granskning av tidigare utförda takterrassprojekt, litteraturstudier, intervju av personer med betydande erfarenhet i ämnet samt att lyfta fram relevanta erfarenheter från tidigare yrkeserfarenheter som stommontör/snickare.I arbetet granskas och förklaras kritiska byggnadstekniska detaljer och kritiska delar av projekteringen för takterrasser. Fördelarna med att en påbyggnad utgörs av en trall i trä belyses. Även vikten av rätt kompetenser vid rätt tillfälle diskuteras.Resultatet av arbetet belyser vikten av ett gediget utförande av tätskikt på takterrasser och varför en extra kontroll av tätskikt kan vara relevant. Det summerar även vad som bör beaktas för att projektera rätt förutsättningar till utförandet.
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Fuktproblem i produktionsskedet : Förebyggande åtgärder och åtgärder efter fuktskadaAndersson, Jasmine, Mård, Oliver January 2023 (has links)
Purpose: The purpose of this study is to examine the problems that occur due to moist in the workplace, as well as the measures that can be taken and which measures are most effective. The study will examine the material storage and how it is being handled in the workplace, exploring what directives the insurance companies have, so the insurance is valid. Lastly the study will compare the different measures based on an economic perspective, time perspective as well as material savings. Method: This study is based on a literature study and a case study. The case study is based on both an interview and a site visit. Information has been gathered from various sources such as books, previously made thesis and various governments websites. The case study for this thesis is conducted at Emausskolan in Västerås. Results: To ensure that the moisture management in the production is good a certified moisture expert is hired. Moisture on materials can be prevented by using just-in-time deliveries and the most optimal solution a weather protection. Directives from the insurance companies regarding moisture management at the workplace and what the entrepreneur is obligated to do after moisture damage has occurred. To minimize moisture and mold growth the workplace should be clean and dry. Self-monitoring and samples were carried out throughout the project to ensure that the work has been performed correctly. Conclusions: The conclusion for this thesis is that challenges for moisture depends on the weather, carelessness, and time pressed schedules. Solutions would be to have a tight climate shell, usage of weather protection and surface treatment on materials. Handling of materials is to a certain degree taken care of in terms of palletized and packaged but not always.
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Chemical emissions from building structures : emission sources and their impact on indoor air / Kemiska emissioner från byggnadskonstruktioner : källor till emissioner och deras påverkan på inomhusluftenGlader, Annika January 2012 (has links)
Chemical compounds in indoor air can adversely affect our comfort and health. However, in most cases there is only a limited amount of information available that can be used to assess their health risk. Instead the precautionary principle is often applied, i.e. efforts are made to ensure that the concentrations of pollutants are kept at a minimum when constructing new buildings or conducting renovations by using low-emitting building materials. Today, when investigating buildings in order to solve indoor air quality problems, volatile organic compounds (VOCs) are sampled in the air within rooms. The chemical composition of indoor air is complex and there are many sources for the chemicals present. The potential for emissions from sources in hidden spaces such as wall cavities is poorly understood and little information exists on the toxic potential of chemical releases resulting from moisture-related degradation of building materials. Most of the non-reactive VOCs that have been detected in indoor air in field studies and from building products are not believed to cause health problems. However, reactive compounds and chemical reaction products have the potential to negatively influence our comfort and health even at low concentrations. Even though the impact of chemical compounds on health is unclear in many cases, they can be used to identify technical problems in buildings. When a building is investigated, the air inside building structures could be sampled. This method would eliminate emissions from sources other than the construction materials and the samples would contain higher levels of individual compounds. The aims of this work was to identify emissions profiles for different types of building structures, to see if the emission profiles for moisture damaged and undamaged structures differed, and to determine whether any of the emissions profiles for specific structures also could be found in indoor air. Technical investigations and VOC sampling were performed in 21 different buildings with and without previous moisture damage. Seven of the buildings were investigated in the years 2005-2006 (study 1) and fourteen in the years 2009-2010 (study 2). In study 1, sixty samples were analyzed by PCA at the chemical group level (18 chemical groups, i.e. aldehydes, ketones etc). 41 % of all identified chemical compounds belonged to the hydrocarbon chemical group. The second largest chemical groups, each of which accounted for 5-10 % of all identified compounds, were alcohols, aldehydes, ketones, polyaromatic hydrocarbons (PAHs) and terpenes. The results indicated that one of the main factors that determined the emissions profile of a building structure was the materials used in its construction. Notably, concrete and wooden structures were found to have different emissions profiles. The sum of VOC (TVOC) concentrations for all 241 samples from both study 1 and study 2 was used to compare total emissions between different building elements (ground and higher floors, external walls and roof spaces). Most building elements exhibited relatively low emissions compared to concrete ground floors, which generally had higher TVOC emissions. Emissions from both polystyrene insulation and PVC flooring could be identified in concrete ground floors and were the main cause for the higher emissions found in these structures. Profiles for wood preservatives such as creosote and pentachlorophenol were also identified in external walls. The emission profiles found in the structures could not be identified in the indoor air in the adjacent rooms, although individual compounds were sometimes detected at low concentrations. Our results showed that the main factors influencing emissions in building structures were the construction materials and the nature of the building element in question. Because of difficulties with finding active water damage at the times of sampling and because of sampling inside closed building structures with old dried-out moisture damages, the field method used in this work was unsuitable for identifying differences in emission profiles between moisture damaged and undamaged structures. It will thus be necessary to investigate this difference in a laboratory where the precise composition of all tested structures is known, a range of RH values can be tested and the accumulation of emissions can be followed. / Kompetenscentrum Byggnad - Luftkvalitet - Hälsa 2 (KLUCK 2)
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Multi-Scale Approach to Design Sustainable Asphalt Paving MaterialsHolcombe, Evan W. 19 September 2017 (has links)
No description available.
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Optimizing the Effective Use of RAP in Local Roadways by Using Recycling Agents.Abushama, Amro 25 September 2018 (has links)
No description available.
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