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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

AnÃlise comparativa de tÃcnicas para estimativa da infiltraÃÃo de Ãgua no solo em irrigaÃÃo por superfÃcie / Comparative analysis of techniques for estimate of the water infiltration in the ground in irrigation for surface

Gleidson Marques Pereira 14 February 2007 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / O estudo teve como objetivo proceder a uma anÃlise comparativa de tÃcnicas para estimativa da infiltraÃÃo de Ãgua no solo, com vistas ao dimensionamento, manejo e avaliaÃÃo de sistemas de irrigaÃÃo por sulcos. O estudo foi conduzido no perÃodo de janeiro a fevereiro de 2006 na Ãrea AT1 da Fazenda Experimental Vale do Curu, Pentecoste, Estado do CearÃ, em um Neossolo FlÃvico de textura franco-arenosa. O delineamento experimental adotado foi o de blocos completamente casualizados, constando de cinco tratamentos e quatro repetiÃÃes. Os tratamentos constaram das seguintes tÃcnicas de infiltraÃÃo de Ãgua no solo: cilindro-infiltrÃmetro, sulco-infiltrÃmetro, entradasaÃda, balanÃo de volume I e balanÃo de volume II. A anÃlise dos resultados permitiu as seguintes conclusÃes: - A lÃmina de Ãgua infiltrada no solo apresentou um maior grau de dependÃncia à variÃvel preparo de solo se comparada à variÃvel teor de Ãgua no solo; - As tÃcnicas de balanÃo volumÃtrico apresentaram resultados semelhantes tanto no que diz respeito à lÃmina infiltrada acumulada quanto ao regime assintÃtico; - As tÃcnicas de entrada-saÃda e cilindro-infiltrÃmetro apresentaram valores de infiltraÃÃo acumulada superestimados se comparados aos demais tratamentos analisados; - As tÃcnicas de balanÃo volumÃtrico apresentaram um menor tempo de resposta à obtenÃÃo do regime assintÃtico, caracterÃstica inerente ao processo fÃsico da infiltraÃÃo de Ãgua no solo. / The study it had as objective to proceed to a comparative analysis of techniques for estimate of the water infiltration in the soil, with sights to the sizing, handling and evaluation of systems of irrigation for furrow. The study was lead in the period of January the February of 2006 in area AT1 of the Fazenda Experimental Vale do Curu, Pentecoste, Cearà State, in one Neossolo FlÃvico of sand loam texture. The adopted experimental delineation was randomized blocks design, consisting of five treatments and four replications. The treatments had consisted of the following techniques of water infiltration in the ground: cylinder infiltrometer, furrow infiltrometer, nflow-outflow, volume balance I and volume balance II. The analysis of the results allowed the following conclusions: - The water infiltrated in the soil presented a bigger degree of dependence to the variable soil tillage if compared with the variable text of water content. - The techniques of volumetric balance had presented resulted similar in what it says respect to the water infiltrated accumulated how much to the asymptotic regime, allowing to recommends the methodology preconized for Christiansen (1966) in situations where the use of the methodology of Walker and Skogerboe (1987) that if present limitation. - The techniques of inflow-outflow and cylinder infiltrometer had presented values of accumulated infiltration overestimated if compared with the too much analyzed treatments, above all to the methodologies of volumetric balance. - The techniques of volumetric balance had presented a lesser time of reply to the attainment of the asymptotic regime, characteristic inherent to the physical process of the water infiltration in the soil.
2

Drinking water quality and the long handled mukombe cup : acceptability and effectiveness in a peri-urban settlement in Zimbabwe

Mwenda, John January 2017 (has links)
Magister Public Health - MPH / Introduction: In-house contamination of drinking water stored in wide-mouthed buckets (even with lids) has been widely reported in epidemiologic investigations as vehicles for diarrhoea disease transmission. The long handled mukombe cup (LHM cup), recently developed by the National Institute of Health Research (NIHR), a department of the Ministry of Health and Child Care (MoHCC) in Zimbabwe, is a promising low cost dipping devise for extraction of water from wide-mouthed containers. Aim: The study aim was to assess the effectiveness and household acceptability of the long handled mukombe cup in reducing bacteriological contamination of drinking water stored in wide-mouthed vessels in the home in a peri urban settlement in Harare, Zimbabwe. Methodology: A randomised controlled trial of a long handled mukombe cup was conducted in Hatcliffe, Harare. After collecting baseline data on demographics, household water quality, and other sanitation and water handling practices, households were given basic health education before the two selected communities were randomly assigned to one of the two groups of 119 households each. The intervention group received the LHM cup while the control group received no intervention. Households were followed up after two months and assessed effectiveness and user acceptability of the intervention. Data Analysis: Data analysis was conducted using STATA 11. Descriptive statistics were calculated and reported as percentages, proportions, frequencies and measures of central tendency. Bivariate statistics were carried out to test independent associations between use of the LHM cup and E. coli. All analyses were conducted in an intention-to-intervene analysis. Results: A total of 230 households were analysed during follow-up. Samples of stored drinking water from intervention households were significantly lower in E. coli levels than those of control households (geometric mean E. coli of 0.8/100 ml vs 13.0/100 ml, p <0.0001). Overall, 78.4% (987/111) of samples from the intervention households met World Health Organization (WHO) guideline value of 0 cfu/100ml sample, while 52.1% of the 119 samples from control households met such a benchmark (p < 0.0001). In addition, 94.6% of intervention household samples were in compliance with this intervention or presented low risk, 27.7% of samples from control group households presented intermediate or high risk. There was a statistically significant association between LHM cup use and reduced E. coli bacterial contamination in stored drinking water (p < 0.05). There was no statistically significant difference in turbidity in both intervention and control groups, both for turbidity <5 and >5 (p = 0.071). Acceptability of the LHM cup was very high (100%). Conclusion: To our knowledge, this is the first study on the evaluation and acceptability of the LHM cup in the Sub-Saharan Africa. Positive results were recorded that showed that the LHM cup was effective in minimising E. coli contamination in the intervention group as compared to the control group. It is postulated that this is because the LHM cup reduces hand contact with stored water during scooping, thus maintaining improved water quality in communities in Zimbabwe that collect and store drinking water in wide-mouthed containers with lids where extraction is by scooping. However, more research is required to document the LHM cup's continued and effective use, durability and overall sustainability in the absence of any serious sampling or monitoring.
3

WATER RESOURCES IN NAKAMTENGA, BURKINA FASO : QUALITY, QUANTITY AND RISKS

Isaksson, Gustav, Andersson, Niklas January 2014 (has links)
Nakamtenga is situated in Burkina Faso, one of the poorest countries in the world suffering from lack of potable water and food security, leading to starvation and illnesses such as diarrhea. The purpose and goal of the field study was consequently to analyze the water situation in Nakamtenga so that the results and conclusions drawn from it could help to improve the water situation. It was done by investigating the water quality, quantity, risks of contamination and how the water is handled. At the time of observation Nakamtenga had seven functioning wells; two open dug wells and five closed pumps. The water quality analyses indicate that the quality is generally good, with exception of the open wells, of which the water has significant amounts of coliforms. The phosphate levels are above 0.6 mg/l in six of the wells, which indicate that the water may be affected by human activities. The most significant threat to the water quality is the handling of the water, which is inappropriate in many ways. Placing of funnels in spill water from the wells, not covering the containers used to store water and placing fetching materials in the dirt are examples of improper handling. Other risks of contamination are lacks in the construction of the wells, latrines placed near the wells and use of pesticides/herbicides. Another major problem is that the pumps break too often; there is water but the inhabitants cannot reach it. It is important to take in consideration that the mapping was made during the dry season. Since conditions are very different during the rainy season it is recommended to do further studies during this period, or at least, being attentive to indications of changes in water quality and supply. To improve the water situation several measures can be taken. Education concerning the handling of the water (hygiene and sanitation) is one of the most important. Actions should also be taken to improve the water quality in the open wells. Reducing contamination risks is possible at all wells since deficiencies and flaws occur everywhere. Moreover the documentation and organization of water related issues is insufficient. Improving this work could significantly improve the water situation in the village.
4

WATER HANDLING PROPERTIES OF VERNIX CASEOSA

GUNT, HEMALI B. 22 May 2002 (has links)
No description available.
5

Avaliação de métodos de manejo da irrigação em pequenas propriedades rurais de base familiar

Lima, Gemael Barbosa 27 August 2013 (has links)
Made available in DSpace on 2016-12-23T14:04:30Z (GMT). No. of bitstreams: 1 Gemael Barbosa Lima.pdf: 2438273 bytes, checksum: 29b39aaf492465438045c512b17e60fd (MD5) Previous issue date: 2013-08-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Irrigation is the most effective way to increase agricultural production. However, if inadequately employed, it can cause significant negative impacts to the environment. In this setting, this study aims at contributing to improving community selfmanagement of water resources by introducing IRRIGAMETRO® and IRRIPLUS® as tools to assist in irrigation and propose guidelines to practical use of these tools. In order to develop this study, the culture chosen was banana (Musa spp.) in its final stadium of development; the management system chosen was microsprinkler; five agricultural family properties (farms) located in the Sossego creek basin, Itarana, ES, Brazil were chosen as pilot. Irrigation practiced based on agriculturist s empirical experience (EXP) usually without any technical criteria were compared to irrigation procedures indicated by IRRIGAMETRO® based on references estimated by IRRIPLUS®. Due to paucity of meteorological data to estimate reference evapotranspiration (ETo), estimation adopted Hargreaves-Samani (HS) equation. However, this equation tends to overestimate ETo and, consequently, overestimate irrigation in relation to the method considered standard by FAO: the Penman-Monteith . Thus, a 15 to 30% range of error to employ HS was established, which was the basis for comparisons. Furthermore, the influence of qualitative improvement of water uniformity distribution coefficient (CUD) was also evaluated. The results of comparisons between EXP and IRRIGAMETRO® and IRRIPLUS® experiences showed that in only one farm irrigation carried out based on experience did not differ statistically (using Dunnett test at 5% of probability) from IRRIPLUS®. In all but one farm, there was difference in the average amount applied indicated by IRRIGAMETRO® compared to IRRIPLUS® and using the same statistical test. In four farms, IRRIGAMETRO® overestimated irrigation (from 5.8% to 39.4%) in relation to the error range of 30%. On the other hand, in all the five farms irrigation was underestimated (from 2.9 to 33.8%) if error range of 15% is considered. As far as EXP irrigation and IRRIPLUS® irrigation are concerned, the study verified that, in two farms, irrigation according to the first method was below (from 10.4 to 15.3%) the estimates by the second method, and for the other farms, it was above (25.8 to 39.2%) for error range of 15%. As for the range of 30%, irrigation according to EXP was overestimated (from 2.8 to 63.8%) compared to IRRIPLUS® in all the study farms. Distribution uniformity improvement allowed higher economy of water, from 42.1% when CUD of 56.1% was set to 95%; and lower economy (10.5%) when CUD of 85.6% was set to 95%. Regarding practical use of IRRIGAMETRO® and IRRIPLUS®, it is seen that for small farmers, the former is more recommended, because the latter requires more advanced training to be operated / A irrigação constitui a forma mais eficiente para o aumento da produção agrícola porém, se praticada de forma inadequada pode causar importantes impactos negativos ao meio ambiente. Nesse contexto, a presente pesquisa objetiva contribuir para o aperfeiçoamento da autogestão comunitária de recursos hídricos através da inserção do IRRIGÂMETRO® e do IRRIPLUS® como instrumentos de auxílio ao manejo da irrigação, propondo diretrizes para a utilização prática de tais ferramentas. Para o desenvolvimento deste trabalho, a cultura agrícola escolhida foi a Banana (Musa spp.), em fase final de desenvolvimento; o sistema de irrigação utilizado foi o de microaspersão; cinco propriedades rurais de base agrícola familiar, situadas na bacia hidrográfica do córrego Sossego, em Itarana/ES, foram tomadas como piloto. As irrigações praticadas pela experiência empírica do produtor rural (EXP), geralmente sem critérios técnicos, foram comparadas com as irrigações indicadas pelo IRRIGÂMETRO®, tomando-se como referência as estimadas pelo IRRIPLUS®. Este último, devido à escassez de dados meteorológicos para estimativa da evapotranspiração de referência (ETo), utilizou-se da equação de Hargreaves-Samani (HS). Entretanto, essa equação tende a superestimar ETo e, consequentemente, superestimar a irrigação em relação ao método que é considerado padrão pela FAO: Penman-Monteith . Por isso, foi estabelecida uma faixa de 15% a 30% de erro do emprego da HS que serviu de base para as comparações. Outrossim, foi avaliada a influência da melhoria qualitativa do coeficiente de uniformidade de distribuição (CUD) da irrigação. Os resultados das comparações entre as irrigações fornecidas por EXP, IRRIGÂMETRO e IRRIPLUS apontaram que, apenas em uma propriedade, a irrigação realizada por EXP não diferiu estatisticamente (pelo teste Dunnett a 5% de probabilidade) do IRRIPLUS®, e em todas as propriedades, à exceção de uma, houve diferença da lâmina de aplicação média indicada pelo IRRIGÂMETRO® em relação ao IRRIPLUS®, considerando o mesmo teste estatístico. Em quatro propriedades o IRRIGÂMETRO® superestimou a irrigação (de 5,8% a 39,4%) em relação à faixa de erro de 30%, mas, por outro lado, nas cinco propriedades a irrigação foi subestimada (de 2,9% a 33,8%) considerando a faixa de erro de 15%. Quanto à comparação das irrigações pela EXP em relação ao IRRIPLUS®, foi verificado que, em duas propriedades, a irrigação de acordo com o primeiro método foi abaixo (de 10,4% a 15,3%) da estimada pelo segundo método, e para as demais foi acima (de 25,8 a 39,2%) para as faixas de 15% de erro. Considerando a faixa de 30%, a irrigação segundo a EXP foi superestimada (de 2,8% a 63,8%) em relação ao IRRIPLUS® em todas as propriedades avaliadas. A melhoria da uniformidade de distribuição proporcionou uma maior economia da lâmina de aplicação, de 42,1%, quando o CUD de 56,1% foi ajustado para 95%; e uma menor economia, de 10,5%, quando o CUD de 85,6% foi ajustado para 95%. Quanto à utilização prática do IRRIGÂMETRO® e do IRRIPLUS®, verifica-se que para os pequenos produtores o primeiro é mais recomendado, uma vez que o segundo exige um nível de capacitação mais avançado para seu uso
6

Miljökvalitetsnormer för vatten i det kommunala detaljplanearbetet - Viktiga faktorer, svårigheter och möjligheter.

Hansson, Caroline January 2016 (has links)
Med målet att uppnå vattenkvalité av god status inom hela EU införde Europaparlamentet år 2000 ramdirektivet för vatten (2000/60/EC), även kallat Vattendirektivet. För att uppnå god vattenstatus sätts mål i form av ”miljökvalitetsnormer”(MKN) på vattendrag, sjöar, kustvatten och grundvatten inom varje län och kommun. Dessa ska beaktas vid framtagandet av nya detaljplaner vilket är ett juridiskt gällande dokument där den tillåtna exploateringen av ett område fastställs. I detaljplanen ska planens påverkan på möjligheterna att uppnå MKN för vatten utredas och presenteras. Det saknas dock tydliga riktlinjer för hur denna bedömning ska göras och vilka aspekter som ska ingå i utredningen. I de fall planen medför att målen i form av MKN riskeras att inte uppnås är det länsstyrelsens uppgift att hindra planen från att godkännas. Syftet med studien är att utreda vad som är viktigt i arbetet att ta fram en detaljplan som beaktar MKN för vatten och hur kommuner och länsstyrelser upplever arbetet. Målet är att undersöka det övergripande arbetet och därefter fokusera på den bedömning som görs av vilken påverkan på MKN en plan medför. Detta för att ge en bild av hur arbetet sker i dagsläget och belysa de utmaningar och förbättringsmöjligheter som finns. Studien avgränsas geografisk till länsstyrelserna inom Norra Östersjöns vattendistrikt och kommunerna i Stockholms län. För att undersöka det ovannämnda genomfördes en förstudie bestående av en intervjustudie riktad till konsulter och anställda på kommun och länsstyrelser, och en litteraturstudie. Förstudien ledde fram till formuleringen av frågor i enkätstudien. Enkätstudien bestod av två delar där den första riktade sig till kommuner i Stockholms län och den andra till länsstyrelserna i Norra Östersjöns vattendistrikt. Resultatet från studien bidrog till att identifiera viktiga steg i processen att ta fram en detaljplan som följer satta MKN. Även svårigheter kopplade till de olika processtegen framkom. Uppföljning visade sig vara ett steg som inte genomförs i så stor utsträckning men som troligtvis kan förbättra situationen genom att bidra med data och kvalitetssäkring av metodiken. Bedömningen som görs av hur en plan påverkar möjligheten att uppfylla MKN sammanställdes i några nyckelsteg. De flesta svårigheter som upplevs av de kommunanställda är kopplade till att utföra den här bedömningen. Främst är det osäkerheter i metod och modelleringsverktyg tillsammans med ofullständigt underlagsmaterial som bidrar till svårigheterna. Det preliminära åtgärdsprogram som presenterats våren 2016 av Vattenmyndigheten inför nästa 6-åriga arbetscykel bidrar förhoppningsvis med att vägledningsmaterial och tydligare riktlinjer tas fram. Detta efterfrågades från flera håll i enkätstudien. Förutom det som åtgärdsprogrammet adresserar ses ett behov av mer utbildning och samverkan av och mellan aktörer. Beräkningsmetoder och underlag som används behöver även ses över och det behöver finnas en tydligare samsyn på hur en detaljplansplans påverkan på MKN ska bestämmas. / With the goal of high quality recipients within the European Union the European Water Framework Directive (WFD; 2000/60/EC) was initiated in the year of 2000. In order to achieve water of high quality, goals have been established under the definition of Environmental Quality Standards (EQS). These are defined for lakes, rivers and other water bodies within each municipality. The EQS are defined as a level that are to be reached until a defined year. The EQS are to be kept in mind when zoning is carried out within a municipality. Zoning allows for strategic use of land and water within the municipality and is an important part in the work of achieving the EQS. If a zoning plan does not meet the EQS the plan should not be adopted. The county government should audit plans before they are approved to make sure the chance of reaching the EQS are not hindered by the plan. The aim of this study is to investigate which important factors that come into play when a zoning plan is created that will meet the EQS. The aim is also to get an understanding of the work from the municipalities perspective as well as from the viewpoint of the county government. Both the overall perspective and the more detailed field of assessing the impact from a zoning plan is to be analyzed. In the end the goal is to give an overview of how the work is done today, which difficulties that are experienced as well as improvements that could be needed. The study is focused upon the county governments within the North Baltic Sea basin and the municipalities within Stockholm county. Semi-structured interviews and a literature review were conducted followed by a survey study in order to address the research questions. The survey study was directed towards the county governments and municipalities within the geographical study area mentioned above. From the methods described above data was collected which resulted in the identification of important steps in the process of making zoning with consideration of the EQS. Also difficulties connected to each phase were identified. The work of follow-up and monitoring was found only to be carried out to a limited extent but is believed to support several important functions in the work, if improved. The impact assessment of zoning on water quality and EQS was found to be one of the more difficult parts of the work with the WFD. Foremost, this process is connected to many uncertainties in the method of calculation but also due to limited data available in some cases. Information needed is for example the current water quality and the levels of pollution connected to different land uses of the area. More developed guidelines and support from central authorities was requested by several participants of the survey. Hopefully the Water authorities’ planned action program for the next 6-year work cycle, will result in this. However, more investigations and studies are needed in order to improve and minimize uncertainties in the methods used to calculate impact from zoning on water quality. More education and cooperation between municipalities, county governments and agencies with issues connected to implementing the WFD is needed as well. Overall more consensus is needed in how the work can be carried out while meeting both environmental and societal goals.
7

Battle and Beating, Water and Waste: Micro-Level Impact Evaluation in Developing and Emerging Economies

Rieckmann, Johannes P. 07 February 2014 (has links)
Die Dissertation mit dem Titel “Battle and Beating, Water and Waste: Micro-Level Impact Evaluation in Developing and Emerging Economies” beinhaltet die Ergebnisse ökonometrischer Wirkungsevaluierungen, die innerhalb zwei verschiedener Themengebieten des täglichen Lebens in Entwicklungs- und Schwellenländern durchgeführt wurden: Gewalt und Wasser. Im ersten dieser Themengebiete konzentriert sich die Analyse auf die Verhaltens-Reaktionen der Bevölkerung, die in räumlicher Nähe zu gewaltsamem Konflikt lebt. Detailliert die Wirkung solcher Exponierung auf das Auftreten häuslicher Gewalt untersuchend, trägt das erste Kapitel – gemeinsam verfasst mit Dominik Noe – dazu bei, die gesellschaftlichen Kosten kriegsähnlicher Auseinandersetzungen abzuschätzen. Insbesondere die Nachwirkungen auf zwischenmenschliche Beziehungen und soziales Verhalten gegenüber Familie und Freunden werden betrachtet. Wir formulieren die Theorie, dass das Leben in Haushalten in der Nähe zu Orten von extrem gewaltsamen Zwischenfällen die Wahrscheinlichkeit von Frauen in diesen Haushalten erhöht, Opfer häuslicher Gewalt zu werden. Diese Theorie überprüfen wir dann anhand von Daten aus Kolumbien; einem Land, in dem sowohl reichhaltige Daten zu Gefechten als auch zu häuslicher Gewalt vorliegen. Die Kernerkenntnis lautet, dass eine höhere Intensität der gewaltsamen Konflikte mutmaßlich die Wahrscheinlichkeit der Frauen, Opfer häuslicher Gewalt zu werden, deutlich erhöht. Das zweite und dritte Kapitel dieser Dissertation sind dem zweiten Themengebiet gewidmet, und hier insbesondere Aspekten des Anschlusses von Haushalten an Leitungswasser und moderne Abwasser-Entsorgung. Das zweite Kapitel – gemeinsam verfasst mit Stephan Klasen, Tobias Lechtenfeld und Kristina Meier – untersucht die Wirkung des Anschlusses von Haushalten an Leitungswasser und Abwasser-entsorgung auf Gesundheit sowie Schul- und Arbeitsplatz-Anwesenheit. Es trägt zu der derzeit noch überschaubaren Anzahl von Wirkungsevaluierungen im Wasser- und Abwasserbereich bei, und ist nach Kenntnis der Autoren die erste rigorose Wirkungsevaluierung im städtischen Umfeld. Quasi-experimentelle Methoden und Wasserqualitäts-Tests unter Berücksichtigung von ungleichmäßiger Infrastruktur-Ausbreitung erlauben es, die Wirkungen separat einerseits für Anschluss lediglich an Leitungswasser, als auch andererseits für zusätzlichen Anschluss an Abwasserentsorgung, zu schätzen. Die Kernerkenntnis lautet, dass Anschluss an Leitungswasser in jemenitischen Städten schädlich sein kann, wenn die Wasserversorgung unregelmäßig ist; und die Wirkung bei regelmäßiger Versorgung im Vergleich zu traditionellen und alternativen Wasserquellen sehr gering ist. Anschluss an Abwasserentsorgung scheint dagegen bei regelmäßiger Wasserversorgung zu gesundheitlichem Nutzen zu führen. Es ist regelmäßig zu beobachten, dass in Aufbereitungsanlagen entkeimtes Leitungswasser innerhalb des Haushaltes rekontaminiert wird. Wasserqualitäts-Tests an Testpunkten entlang der Versorgungskette innerhalb des Haushaltes erlaubt Rückschlüsse auf Ort und Quelle der Kontaminierung. Der Löwenanteil dieser Verschlechterung der Wasserqualität ist auf Verhalten im Zusammenhang mit Wasser-Handhabung und Hygiene zurückzuführen. Das in Alleinautorschaft verfasste dritte Kapitel baut auf dem zweiten auf und untersucht, welche treibenden Faktoren hinter Verhaltensaspekten stehen, die Rekontaminierung verhindern würden. Spezifisch die Determinanten von Wasserbehandlung und Hygiene werden untersucht, und vor dem Hintergrund der Erkenntnisse aus dem zweiten Kapitel interpretiert. Die Kernerkenntnis lautet, dass Hygiene-Training, Zugang zu Informations- und Kommunikations-Technologie sowie Schulbildung mutmaßlich zu den relevanten, beeinflussbaren Determinanten zählen. Anschluss an Leitungswasser und Abwasserentsorgung – welche üblicherweise bestenfalls mittelfristig ausgebaut werden können – haben scheinbar ebenfalls wünschenswerte Effekte, allerdings in geringerem Maße, und in höherem Maße bei Leitungswasser als bei zusätzlicher Abwasserentsorgung.
8

Påldrivning: Jämförelse mellan luft- och vattendriven borrning : En utredning av jämförelser avseende slitage, logistik och driftkostnader

Bengtsson, Andreas, Bodin, Pierre January 2022 (has links)
Skanska Grundläggning in Region Special wishes to gain an increased understanding of the extent to which it differs in the wear of percussion hammers and pilot drill crowns, depending on which driving medium is used in down-the-hole drilling, as well as logistical and economic aspects depending on the chosen method. Down-the-hole drilling means that the hammer works down in the borehole and forms one of the components at the far end of the drill string together with a drill bit. The blow of the hammer is created by air or water at high pressure. The piling method that is examined is drilled steel pipe piles, which means that a steel pipe pile is driven into the ground in step with the hammer and the drill bit's advancement. Once the desired depth has been reached, the drill string with the drill bit is pulled out of the casing and then the steel pipe pile is filled with concrete. The study aims to examine the products' lifespans and repair intervals from several different perspectives and set them against reality, as well as what the different methods have for differences regarding logistics and establishment. This is to create a basis for future decisions on the most suitable method of down-the-hole drilling. The beginning of the study consisted of qualitative preliminary interviews to identify and create a problem formulation that was dealt with via a literature study, five semi-structured interviews, eleven questionnaires, internal data from drilling protocols and purchasing. The result shows that there is some difference in wear in the hammer depending on whether it is an air or water powered system, the wear appears in different places and can have an impact on the life of the hammer. The wear that occurs most frequently on drill bit is grinding on the buttons. Geotechnical differences for various projects are a significant factor in the service life of the equipment. An air hammer requires that the air constantly being mixed with lubricating oil and that an air compressor consumes more diesel compared to a high-pressure pump for the equivalent water hammer. The handling of water that is flushed out of the borehole is considered a concern. To reduce wear on water hammers and thus fewer replacements and more repairs, a drill bit intended for water powered down-the-hole hammer should be used. DTH-drilling with an air hammer is considered an industry standard and a certain skepticism towards a water powered system may indicate inexperience. / Skanska Grundläggning inom Region Special önskar att få en ökad förståelse hur vida det skiljer sig vid slitage av hammare och pilotborrkrona beroende på vilket drivande medium som nyttjas vid sänkhammarborrning, samt logistiska och ekonomiska aspekter beroende på vald metod. Sänkhammarborrning innebär att hammaren arbetar nere i borrhålet och utgör en av komponenterna längst ut på borrsträngen tillsammans med en borrkrona. Hammarens slag skapas av luft eller vatten i högt tryck. Pålningsmetoden som undersöks är borrade stålrörspålar, det betyder att ett foderrör drivs ned i marken i takt med hammaren och borrkronans framfart. Väl när önskat djup uppnåtts lyfts borrsträngen med hammaren och piloten upp ur foderröret för att sedan fyllas upp med betong. Studien syftar till att undersöka produkternas livslängder och reparationsintervall från flera olika perspektiv och ställa dem emot verkligheten, samt vad dem olika metoderna har för olikheter kring logistik och etablering. Detta är för att skapa underlag för framtida beslut om mest lämplig metod av sänkhammarborrning. Studiens begynnelse bestod av kvalitativa förintervjuer för att identifiera och skapa en problemformulering som avhandlades via en litteraturstudie, fem semistrukturerade intervjuer, elva frågeformulär, interna data från borrningsprotokoll och inköp. Resultatet visar att det förekommer viss skillnad i slitage i hammaren beroende på om det är en luft- eller vattenanläggning, slitaget visar sig på olika ställen och kan ha betydelse för hammarens livslängd. Det slitage som uppträder mest frekvent på piloter är nedslipning av stift. Geotekniska egenskaper för olika projekt utgör en betydande faktor för utrustningens livslängd. En lufthammare är i behov av att luften konstant beblandas smörjolja och att en luftkompressor förbrukar mer diesel jämfört med en högtryckspump för motsvarande vattenhammare. Efterhanteringen av vatten som spolas upp anses vara ett bekymmer. För att minska slitage på vattenhammare och därmed färre byten och mer reparationer bör en pilotborrkrona avsedd för vattendriven sänkhammarborrning nyttjas. Sänkhammarborrning med lufthammare anses som branschstandard och en viss skepticism mot en vattendriven anläggning kan tyda på oerfarenhet.

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