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Cementproduktion står idag för totalt 5 % av koldioxidutsläppen globalt, vilket t.ex. är mer än dubbelt så mycket som den globala flygindustrin. Nya cement- och betongrecept, med nya egenskaper, utvecklas med målet att minska klimatbelastningen. I produkten Bascement ersätts delar av klimatbelastande cementklinker med mineraltillsatsen flygaska, en restprodukt från andra industrier. Detta ska alltså leda till en minskad klimatbelastning. Betong med Bascement har dock orsakat förseningar och extra kostnader i produktion på grund av långa torktider som inte stämt överens med simuleringar i TorkaS 3.2, en programvara baserad på betong med Byggcement. TorkaS ska ersättas av programvaran Produktionsplanering Betong (PPB) som kan simulera uttorkning i betong med Bascement. Målet med studien är att undersöka hur fuktsimuleringar i PPB skiljer sig jämfört med genomförda fuktmätningar i fyra betongprover med två olika vattencementtal, vct. Genom att förvara proverna i olika miljö är målet att experimentellt mäta hur omgivningen påverkar uttorkningen. Målet är vidare att visa skillnader mellan fuktsimuleringar med inbyggd klimatdata i PPB och med egna uppmätta klimatdata. Resultaten från de experimentella undersökningarna visar att uttorkningen blev större i betongprover med vct 0,40 än för motsvarande prover med vct 0,55 efter 70 dagar. Prover som hade förvarats i en stabil inomhusmiljö hade torkat mer än prover som hade förvarats i en varierande utomhusmiljö, vilket i denna studie inte stämde överens med simuleringar i PPB. Resultatet i denna studie visar att simuleringar i PPB tenderar att visa något större uttorkning jämfört med genomförda fuktmätningar. Denna överskattning blir större vid simuleringar med en varierande utomhusmiljö än med en stabil inomhusmiljö. Överskattningen blir större vid simuleringar med inbyggd klimatdata i PPB än med egna uppmätta klimatdata. Vid justering av betongens maxtemperatur i PPB till verkligt uppmätt maxtemperatur påverkas fuktsimuleringarna positivt så att de närmar sig de experimentellt erhållna resultaten. Betong med låga vct påverkas mer av en sådan justering än höga vct. Slutsatsen i denna studie är baserad på simuleringar och fuktmätningar i ett fåtal betongprover, vilka kan ha utsatts för störningar. Fler studier behövs för att validera reliabiliteten hos programvaran PPB. Val av härdningsmetod samt maxtemperatur under härdning kan påverka uttorkningen och simuleringar i PPB. Experimenten indikerar att simuleringar med PPB tenderar att avvika om betong med höga vct utsätts för vattentillskott kort efter gjutning. Korrekt maxtemperatur i PPB är viktigt för en mer verklig simulering av uttorkning i betong, särskilt vid låga vct. Simuleringar i PPB tenderar att bli mer korrekta med egna klimatdata än med inbyggd klimatdata. / Cement production currently accounts for a total of 5 % of carbon dioxide emissions globally, which for example is more than twice as much as the global aviation industry. New cement and concrete recipes, with new properties, are being developed with the aim of reducing the climate load. In the Portland fly ash cement, parts of climate-stressing cement clinkers are replaced with the mineral-added fly ash, a residual product from other industries. This should lead to a reduced climate impact. Concrete with Portland fly ash cement, however, has caused delays and extra costs in production due to long drying times that did not match with simulations in the software TorkaS 3.2, which is based on concrete with Portland-limestone cement. TorkaS will be replaced by the software Production Planning Concrete, PPB, which can simulate dehydration in concrete with Portland fly ash cement. The aim of the study is to investigate how moisture simulations in PPB differ from executed moisture measurements in four concrete samples with two different w/c ratio. By storing the samples in different environments, the goal is to experimentally measure how the environment affects the dehydration. The goal is also to show differences between moisture simulations with the built-in climate data in PPB and with the own measured climate data. The results from the experimental studies show that the dehydration became larger in concrete samples with w/c ratio 0.40 than for samples with w/c ratio 0.55 after 70 days. Samples that had been stored in a stable indoor environment had dried more than samples that had been stored in a varying outdoor environment, which in this study did not correspond to simulations in PPB. The result of this study shows that simulations in PPB tend to show slightly greater dehydration than executed moisture measurements. This overestimation is greater in simulations with a varying outdoor environment than with a stable indoor environment. The overestimation is greater in simulations with the built-in climate data in PPB than with the own measured climate data. When adjusting the maximum temperature of the concrete in PPB to the actual measured maximum temperature, the moisture simulations is positively affected so that they approach the experimentally obtained results. Concrete with low w/c ratio is more affected by such an adjustment than concrete with high w/c ratio. The conclusion in this study is based on simulations and moisture measurements in a few concrete samples, which may have been exposed to disturbances. More studies are needed to validate the reliability of the PPB software. Choice of curing method and maximum temperature during curing can affect the drying and simulations in PPB. The experiments indicate that simulations with the PPB software tend to deviate if concrete with a high w/c ratio is exposed to water shortly after casting. Correct maximum temperature in PPB is important for a more real simulation of dehydration in concrete, especially at high w/c ratio. Simulations in PPB tend to be more accurate when using own climate data than using the built-in climate data.

Esta pesquisa apresenta uma revisão bibliográfica sobre as emissões de metano em aterros sanitários, os conceitos de geração de gases em aterros sanitários, movimentações de gases em aterro, apresenta os métodos de medição de gases in situ, tipos de cobertura finais para aterros e a oxidação do metano na camada de cobertura. A pesquisa também tem como objetivo medir as emissões de gases e avaliar a infiltração das águas pluviais através da camada de cobertura do aterro sanitário da CTR Nova Iguaçu. As medições foram realizadas nos meses de julho a novembro de 2010, na camada de cobertura monolítica existente e em outra construída sobre uma barreira capilar. Sensores para medir temperatura e umidade foram instalados em profundidade nas duas camadas. Foram realizados ensaios de placa de fluxo para medir a composição dos gases e o fluxo através dos dois tipos de camadas, e avaliadas duas situações: com os poços de extração de gás ativos e desligados. Os sensores indicaram que em período de baixa pluviosidade, a barreira capilar apresenta uma eficácia superior à camada monolítica, e com a intensificação das chuvas, as umidades medidas nos dois tipos de camadas aumentam, e na barreira capilar o gradiente estabelecido entre os sensores diminui, indicando uma possível tendência à saturação desta barreira capilar. Porém, com a paralisação das chuvas, recupera e retoma sua condição inicial. Os resultados de medidas dos gases demostraram a eficiência do sistema de extração de gás quando ativado, resultando em emissões quase nulas de metano e gás carbônico nos dois tipos de camadas. No entanto, quando o sistema está desativado, as emissões através da camada monolítica são cerca de 3 vezes maiores do que através da barreira capilar. / This research presents a literature review on methane emissions from landfills, the concepts of landfill gas generation, the landfill internal gas flow, introduces the methods of measurement of gases "in situ", types of final landfill coverage and the methane oxidation in the cover layer. The research also purposes to measure greenhouse gas emissions and to evaluate the infiltration of rainwater through the landfill cover layer of the CTR Nova Iguaçu. Measurements were made in the months from July to November 2010, the existing monolithic cover layer and another built on a capillary barrier. Sensors to measure temperature and humidity were installed in two layers in depth. Plate assays were performed to measure the flow of the gas composition and flow through the two types of layers, and evaluated two situations with the gas extraction wells active and off. The sensors have indicated that in times of low rainfall, the capillary barrier has superior efficacy to the monolithic layer, and with the intensification of rain, the moisture content measured on two types of layers increase, the capillary barrier and the gradient established between sensors decreases, indicating a possible trend to saturation of capillary barrier. However, with the stoppage of rain, recovers and returns to its initial condition. The results of measurements of gases demonstrated the efficiency of extraction of gas when activated, resulting in near zero emissions of methane and carbon dioxide in the two types of layers. However, when the system is off, the emissions through the monolithic layer is about three times larger than through the capillary barrier.

Esta pesquisa apresenta uma revisão bibliográfica sobre as emissões de metano em aterros sanitários, os conceitos de geração de gases em aterros sanitários, movimentações de gases em aterro, apresenta os métodos de medição de gases in situ, tipos de cobertura finais para aterros e a oxidação do metano na camada de cobertura. A pesquisa também tem como objetivo medir as emissões de gases e avaliar a infiltração das águas pluviais através da camada de cobertura do aterro sanitário da CTR Nova Iguaçu. As medições foram realizadas nos meses de julho a novembro de 2010, na camada de cobertura monolítica existente e em outra construída sobre uma barreira capilar. Sensores para medir temperatura e umidade foram instalados em profundidade nas duas camadas. Foram realizados ensaios de placa de fluxo para medir a composição dos gases e o fluxo através dos dois tipos de camadas, e avaliadas duas situações: com os poços de extração de gás ativos e desligados. Os sensores indicaram que em período de baixa pluviosidade, a barreira capilar apresenta uma eficácia superior à camada monolítica, e com a intensificação das chuvas, as umidades medidas nos dois tipos de camadas aumentam, e na barreira capilar o gradiente estabelecido entre os sensores diminui, indicando uma possível tendência à saturação desta barreira capilar. Porém, com a paralisação das chuvas, recupera e retoma sua condição inicial. Os resultados de medidas dos gases demostraram a eficiência do sistema de extração de gás quando ativado, resultando em emissões quase nulas de metano e gás carbônico nos dois tipos de camadas. No entanto, quando o sistema está desativado, as emissões através da camada monolítica são cerca de 3 vezes maiores do que através da barreira capilar. / This research presents a literature review on methane emissions from landfills, the concepts of landfill gas generation, the landfill internal gas flow, introduces the methods of measurement of gases "in situ", types of final landfill coverage and the methane oxidation in the cover layer. The research also purposes to measure greenhouse gas emissions and to evaluate the infiltration of rainwater through the landfill cover layer of the CTR Nova Iguaçu. Measurements were made in the months from July to November 2010, the existing monolithic cover layer and another built on a capillary barrier. Sensors to measure temperature and humidity were installed in two layers in depth. Plate assays were performed to measure the flow of the gas composition and flow through the two types of layers, and evaluated two situations with the gas extraction wells active and off. The sensors have indicated that in times of low rainfall, the capillary barrier has superior efficacy to the monolithic layer, and with the intensification of rain, the moisture content measured on two types of layers increase, the capillary barrier and the gradient established between sensors decreases, indicating a possible trend to saturation of capillary barrier. However, with the stoppage of rain, recovers and returns to its initial condition. The results of measurements of gases demonstrated the efficiency of extraction of gas when activated, resulting in near zero emissions of methane and carbon dioxide in the two types of layers. However, when the system is off, the emissions through the monolithic layer is about three times larger than through the capillary barrier.

När människors hälsobesvär misstänks vara byggnadsrelaterat är det viktigt att klarlägga källan till problemet. Fukt kan vid högre nivåer ge upphov till mikrobiella eller kemiska reaktioner som orsakar emissioner från byggnadsmaterial som kan ha negativa hälsoeffekter. För att utreda om byggnaden är problemkällan görs skadeutredningar. I utredningarna är det viktigt att identifiera vilka emissioner som förekommer i inomhusmiljön för att kunna åtgärda den eventuella skadan. Med hjälp av fuktprofiler som skapas genom fuktmätningar kan det utredas om varifrån fukten kommer. En vanlig orsak i Norden till förhöjda koncentrationer av emissioner i inomhusmiljön är fuktskadade betongkonstruktioner med en pålimmad plastmatta. I en sådan konstruktion utgör plastmattan ett tätt skikt som inte låter fukten i betongen avdunsta. Betong, som är alkalisk, kan i kombination med höga fuktnivåer utlösa en kemisk process, så kallad alkalisk hydrolys, som bryter ned mjukgörare i golvlim och PVC-mattor. Detta leder till att nedbrytningsprodukterna 2-etyl-1-hexanol och n-butanol dels emitteras till inomhusluften och dels migrerar ned i betongen där de fixeras. Det är i det skedet betongen blir emissionsskadad på grund av att de kemiska ämnena som fixerats i betongen kan lagras där under en lång tid och kan om förhållandena förändras, exempelvis vid renovering, avge dessa ämnen till inomhusluften. Eftersom 2-etyl-1-hexanol och n-butanol utgör majoriteten av nedbrytningsprodukterna, används de därför som indikatorämnen vid skadeutredningar. Om indikatorämnena upptäcks i inomhusluften är det troligt att en skada i golvkonstruktionen har inträffat och detta kontrolleras då med fuktmätningar. Problemet med fuktmätningar i emissionsskadad betong är dock att det befaras av fuktskadeutredare att dessa indikatorämnen påverkar fuktmätningarna genom att man mäter till en lägre relativ fuktighet (RF) än vad det faktiskt är. Examensarbetet är utformat som ett experimentellt arbete med fuktmätningar som utförts i Polygon AK:s laboratorium. I laborationerna testades huruvida indikatorämnena, 2-etyl-1-hexanol samt n-butanol, påverkar fuktmätningar. Detta gjordes genom att prover med ren betong först RF-bestämdes för att sedan droppa i ovanstående ämnen i proverna och därefter följdes utvecklingen i RF. Vidare kontrollerades eventuell drift i mätinstrumenten genom egenkontroller både före och efter varje uppföljning. Mätresultaten från gjorda försök visade att den effekt som befarats av skadeutredare ej märkts av, det vill säga att indikatorämnena skulle ha en påverkan genom att fuktnivån mäts till något lägre jämfört med den verkliga fuktnivån. Effekten påvisades varken genom lägre uppmätta fuktnivåer eller genom mätinstrumentens drift. / When people's illness are suspected to be building-related, it is important to clarify the source of the problem. Moisture at higher levels can trigger microbial or chemical reactions which causes emissions from building materials that may have adverse health effects. In order to investigate whether the building is the source of the problem or not, indoor environment investigations are conducted to investigate the matter. In the investigations it is important to identify what kind of emissions that occurs in the indoor environment in order to fix the possible damage or damages. Using moisture profiles created with moisture measurements, it is possible to determine where the moisture comes from. A common cause in the Nordic countries for increased concentrations of emissions in the indoor environment is moisture-damaged concrete structures with a glued plastic mat. In such constructions, the plastic mat is a compact layer that does not allow the moisture in concrete to evaporate. Concrete, which is alkaline, can in combination with high moisture levels trigger a chemical process, called alkaline hydrolysis, which degrades plasticizers in floor adhesives and plastic mats. This results in the degradation products 2-ethyl-1-hexanol and n-butanol, which are being emitted to the indoor air and partly migrating down into the concrete where they are fixed. At that moment the concrete gets emission-damaged because of the degradation products that has been fixed into the concrete where they can be stored for a long time and can with changed conditions, for instance during renovation, emit these degradation products to the indoor air. Since 2-ethyl-1-hexanol and n-butanol constitutes the majority of degradation products, they are therefore used as indicators during damage investigations. If the indicators are detected in the indoor air, it is likely that a damage has occured in the floor construction and this is later checked with moisture measurements. However, the problem with moisture measurements in emission-damaged concrete is that some investigators fears that these indicators affects the moisture measurements by measuring a lower relative humidity (RH) than it actually is. The thesis is structured as an experimental work with moisture measurements performed in Polygon AK's laboratory. In the laboratory it was tested whether the indicators, 2-ethyl-1-hexanol and n-butanol, affects moisture measurements. This was done with specimens of pure concrete by first determining the RH followed by dropping the indicators into the samples and then the development in RH was followed. Furthermore, eventual drifting in the measuring instruments was checked before and after each follow-up. The measurement results from the experiments showed no effect of what the damage investigators feared of, that the indicators would have an impact by measuring the moisture level lower than the actual moisture level. The effect was not detected either by lower measured humidity levels or by drifting of the measuring instruments.