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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.
111

Faktorer för effektiv infiltration av dagvatten hos permeabel asfalt / Factors for effective infiltration of storm water in permeable asphalt

Hedlöf Ekvall, Linnea January 2019 (has links)
För att permeabel asfalt skall vara ett bra sätt att ta hand om dagvatten i en stad med allt fler hårdgjorda ytor är det viktigt att den långsiktigt kan infiltrera dagvatten. Då det inte går att undvika att permeabel asfalt utsätts för små partiklar finns det en risk för att den skall sätta igen och förlora sin förmåga att infiltrera dagvatten. Som en skötselåtgärd för att förhindra att den sätter igen kan rengöring med högtryckstvätt och vakuumsugning göras. I detta examensarbete undersöktes det vilken effekt rengöring med högtryckstvätt och vakuumsugning har på permeabel asfalts infiltrationskapacitet. Vidare undersöktes även vilken typ av uppbyggnad av den permeabla asfalten som var mest lämplig för en effektiv infiltration. Litteraturstudie och intervjuer om permeabel asfalt samt infiltrationsförsök har utförts. För att uppbyggnaden av permeabel asfalt hydrologiskt sett skall fungera på ett bra sätt framkom det, i litteraturstudier och intervjuer, att det är viktigt att alla lager i uppbyggnaden verkligen är permeabla och att uppbyggnaden bör anpassas efter rådande förhållanden på anläggningsplatsen. Förhållanden som till exempel bör tas hänsyn till är underliggande jordart och närheten till grundvattenyta. I litteraturstudier och intervjuer framkom det att regelbunden skötsel av den permeabla asfalten är mycket viktig för dess långtidsfunktion att kunna infiltrera dagvatten. Infiltrationsförsöken skedde på två platser med permeabel asfalt i Uppsala; på en parkering vid ett köpcentrum i Gnista och på en lokalgata i Gränby backe. Infiltrationskapaciteten uppmättes innan och efter rengöring med högtryckstvätt och vakuumsugning på den permeabla asfalten. Vid Gnista kunde ingen infiltration uppmätas varken före eller efter rengöring. I Gränby backe ökade infiltrationskapaciteten från 0,47–0,71 mm/min till 1,24–12,23 mm/min efter rengöring. Denna infiltrationskapacitet visar på att den permeabla asfalten i Gränby backe kunde infiltrera dimensionerade regn med allt från 7 års återkomsttid till över 1000 års återkomsttid och med 10 minuters varaktighet. Det framkom i litteraturstudien att högtryckstvätt och vakuumsugning i olika studier har haft en positiv effekt på att upprätthålla och till viss del återskapa infiltrationskapaciteten hos permeabel asfalt. Vid infiltrationsförsöken i detta examensarbete påvisades även en positiv effekt, till viss del, av denna rengöringsmetod på infiltrationskapaciteten. Utifrån detta skulle rengöring med högtryckstvätt och vakuumsugning kunna rekommenderas som skötselmetod på permeabel asfalt.  Resultaten i Gnista skiljde sig från de i Gränby backe då det i Gnista varken före eller efter rengöring fanns någon infiltrationskapacitet. Det skiljer sig endast ett år i ålder mellan de båda försöksplatserna, de har skötts på liknande sätt sedan anläggning och litteratur visar på att rengöring med högtryckstvätt och vakuumsugning skall ha en effekt på infiltrationskapaciteten. Detta kan tyda på att bristen på infiltrationsförmåga i Gnista kan bero på något annat än igensättning av den permeabla asfalten. / It is important that permeable asphalt is able to infiltrate storm water in the long-term for it to be a viable alternative for handling storm water. Permeable asphalt will always, in some way, be exposed to fine particles and therefore there is a risk that clogging will occur and that the permeable asphalt will lose its ability to infiltrate storm water. As a mean of maintenance cleaning with high pressure washing and vacuum cleaning can be done to prevent clogging. In this master thesis the effect of high pressure washing and vacuum cleaning on the infiltration capacity of permeable asphalt was examined.  Also, the most suitable type of substructure for effective infiltration was examined. A literature study and interviews were conducted in combination with infiltration experiments on two locations with permeable asphalt in Uppsala. Literature studies and interviews state that for the substructure to be hydrologically well functioning it is important that every layer in the substructure really is permeable. The substructure should also be adapted to the conditions at the site where it is built. For example, conditions to take into consideration are soil type and highest level of groundwater. All through literature and interviews regular maintenance is said to be very important for the long-term functioning and infiltration of permeable asphalt. The infiltration experiments were conducted at a parking lot at a shopping center in Gnista and a small local street in Gränby backe. The infiltration capacity of the permeable asphalt was measured before and after maintenance with high pressure washing and vacuum suction. No infiltration capacity could be measured before or after maintenance at Gnista. In Gränby backe the infiltration capacity was 0,47-0,71 mm/min before maintenance and 1,24-12,23 mm/min after. According to this infiltration capacity the permeable asphalt in Gränby backe can infiltrate design rains with return periods of 7 years to over 1000 years and with a duration of 10 minutes. In research, high pressure washing, and vacuum suction were found to be able to maintain, and in some cases restore, infiltration capacity. In this master thesis’ infiltration experiments a positive effect on infiltration capacity by cleaning with high pressure washing and vacuum suction was partially found. According to this high pressure washing and vacuum suction can be recommended as a maintenance method on permeable pavement. The results from the two experiment sites stood apart from each other as Gnista had no infiltration capacity neither before nor after cleaning. In age, the two sites only differ by one year, and since they were built they have received similar maintenance and literature shows that high pressure washing and vacuums suction have an effect on infiltration capacity. This might indicate that the lack of infiltration capacity at Gnista might be due to something else than clogging.
112

Les objets de nature : Quelles places dans la ville ? Conditions d’appropriation des dispositifs de gestion des eaux pluviales de la métropole lyonnaise / Natural objects : What places in the city? Conditions for appropriation of the rainwater management systems of the Lyon metropolis.

Ah Leung, Sébastien 23 June 2017 (has links)
En France, face aux problèmes liés au réseau d’assainissement hérité du XIXème siècle, une solution consiste à gérer les eaux pluviales par des techniques « alternatives » au réseau. Le « tout tuyau » fait place à un ensemble d’objets techniques hybrides, composés d’éléments naturels et de matériaux synthétisés. Ces « objets de nature » présentent une apparence mixte (naturelle/artificielle) et assurent des fonctions multiples qui peuvent rendre leur intégration difficile. Dans quelles mesures l’appropriation des objets de nature par les publics est-elle difficile? Comment s’établit la place des objets de nature dans la ville? Cette thèse vise plusieurs objectifs. Il s’agit de renseigner les relations entre publics et objets de nature, d’obtenir des éléments sur les pratiques et usages des publics et d’apporter une réflexion sur la manière d’étudier les comportements humains. Pour se faire, trois enquêtes basées sur de l’observation directe doublée par une prise d’images systématisée ont été menées au cours de quatre saisons et à travers 12 études de cas réparties au sein de la métropole lyonnaise. Ces enquêtes ont tout d’abord permis de préciser la construction de l’objet de nature en tant qu’instrument à travers le concept de genèse instrumentale de Rabardel. Ensuite, les pratiques, usages ainsi que les conditions d’utilisation des dispositifs ont pu être définis grâce aux comportements observés chez les publics. Enfin, les avantages et limites de l’observation directe et des conditions d’analyse des données ont été discutés dans le but d’apporter des pistes d’amélioration à cette méthodologie pour de futures études. / To better manage storm water and to respond to problems related to the sanitation networks conceived in the 19th Century, some alternative techniques, other than networks, are being put forward. The “all tubes” concept is giving way to various technical objects of a hybrid nature made up of natural components and synthesized material. The physical appearance of these “natural objects” is double (both natural and artificial) and they fulfil various purposes. Thus, their insertion in the landscape can be delicate. How are these natural objects seized by society? In this process are any difficulties encountered? How is the place for natural objects defined in a city? The purpose of this dissertation is triple: (1) gather information on the relationship between societies and natural objects, (2) collect data on the public's use and practices, (3) discuss a methodology to study human behavior. Three inquiries were carried out during the four seasons of the year and in twelve sites; they were based on direct observation and systematized photography. Based on the fieldwork and the concept of “genèse instrumentale” developed by Rabardel, a discussion was developed on the building of a natural object as a tool. Subsequently, based on the observation of the public, practices, uses and the conditions in which these natural objects are used were defined. The dissertation concludes by highlighting the advantages and the limits of direct observation, and by developing the biases such as the context in which the data was analyzed, in order to suggest some possible methodological enhancements which could help future studies.
113

Bestämning av vattendelare i urban miljö : Metod för avgränsning av avrinningsområden i ArcGIS utgående från dagvattensystemet / Watershed delineation in urban catchment areas : Method for delineating catchment areas in ArcMap based on storm-water drains

Calestam, Karl-Martin January 2013 (has links)
Växande städer leder till att naturmark omvandlas till stadsmiljöer. Det skapar mer hårdgjorda ytor och därmed ökade volymer dagvatten som behöver hanteras. Modellering av dagvattennätet används ofta för att bedöma kapaciteten och risk för översvämningar. Avrinningsområdets storlek är en avgörande parameter för att bedöma hur mycket vatten som kommer till en viss ledning. Traditionellt har automatisk bestämning av avrinningsområden gjorts enbart utifrån topografin. I områden med dagvattennät styr däremot ledningarnas sträckning i första hand hur vattnet rinner, och de följer inte nödvändigtvis terrängen. ArcHydro Tools, som är ett tilläggsprogram till ArcMap, har utvecklats för att beräkna topografiska avrinningsområden. Genom att programmera en tilläggsfunktion i Python har processen i ArcHydro Tools anpassats för att kunna ta hänsyn till dagvattennätet. Dagvattennätet approximerades som vattendrag. Tryckledningar och tunnlar tillåter inte något inflöde av vatten. Därför beskrevs dessa som ändpunkter i ledningsnätet, varifrån vattnet inte rann vidare. Funktionen som skapades i det här examensarbetet tillät att vattnet stannade i dessa punkter, till skillnad från i den ursprungliga metoden. Den utgick istället från att vattnet rann till kanten av det undersökta området, vilket i de här fallen skulle ha resulterat i felaktigt avgränsade avrinningsområden. Tilläggsfunktionen anpassades för att användas som övriga funktioner i ArcMap och testades på data över Lidingö stad. Resultatet visade att det var möjligt att utnyttja topografiskt baserade metoder för bestämning av avrinningsområden så att avgränsningen istället skedde med utgångspunkt i dagvattennätet. Det är ett steg mot att effektivisera processen för bestämning av avrinningsområden för användning vid hydrologisk modellering av dagvattennätet. Behovet av manuell bearbetning minskas. Ett försök att i ArcMap implementera en funktion för efterbehandling av avrinningsområden gjordes också. Funktionen letar upp avrinningsområden som bedöms som för små och lägger ihop dem med ett närliggande område. Avrinningsområden som beräknats med den modifierade metoden har senare använts vid modellering av dagvattennätet i Molkom, Värmland. / Growing populations result in expanding cities. An increase in the amount of impervious surfaces in the area will follow and thereby generate more storm water. The capacity of the drainage system can be evaluated using hydraulic modelling. The model highly depends on the catchment areas, which will determine the water volume each pipe section receive. Watershed delineation is usually done based on the topography. However, if a storm water drainage system is present, it may route the water in a different direction than the slope indicates. ArcHydro Tools is an extension to ArcMap and is commonly used to delineate catchment areas. The method heavily relies on topography during this process. A function has been developed during the course of this project to allow for the drainage system to be the primary source of information for watershed delineation. This function made sure that outlets in the model were to be evaluated as such, even if they happen to be located in the middle of the area of interest. The water is therefore not necessarily routed to the edge of the elevation model, but can be allowed to stay at the appropriate position. In order to do this, the drainage system was represented as a stream network. The new method was applied to test data supplied by Lidingö city, Stockholm, Sweden, and included elevation data and information about the drainage system. The result implies that it is indeed possible to use the drainage system as a base for delineation of catchment areas. A more efficient method of calculating catchment areas will reduce the required amount of manual processing, thereby saving time and resources. Another function, for finishing up the resulting catchment areas, is proposed but not fully implemented. The whole process was used to delineate catchment areas for Molkom, County of Värmland, Sweden. The resulting watersheds were later successfully used for modelling the storm water drains in the area.
114

Mineraliska material som reaktiva filter för avskiljning av tungmetaller från dagvatten

Lindquist, Anna January 2005 (has links)
Highly polluted urban storm water from e.g. highways can contain large amounts of heavy metals that may cause harm if they are discharged into recipients. To remove the heavy metals a possible low-cost method that does not require much maintenance, could be the use of reactive filters with filter materials consisting of industrial residues or other cheap mineral based materials. Dissolved metal ions are removed by reactive filters through the processes of ions binding to active sites on the surface of the filter materials, or by formation of insoluble precipitates. The ability of CaO-treated granulated blast-furnace slag, iron oxide coated sand, olivine and nepheline to remove seven heavy metals (Cr, Cd, Cu, Ni, Zn, Pb and Hg) from urban storm water was studied. Initially batch experiments were performed where the effect of pH, dissolved organic carbon (DOC) and dissolved ions on the adsorption efficiency was studied. The experiments were conducted with urban storm water and with a reference solution (10 mM NaNO3), both containing the same concentration of heavy metals (approx. 1 μM). The two materials with the best results were further investigated in a column study, where the capacity of the filter was tested. Chemical equilibrium calculations using the program Visual MINTEQ were performed in order to assess the role of precipitation as a mechanism for removal. The results show that the blast-furnace slag was the most effective filter material and that it has great potential to be used as a heavy metal remover. Also the iron oxide coated sand worked satisfactory. The highest degree of removal was obtained for lead, cadmium and nickel, for which the removal efficiency exceeded 90% after a load of 300 times the water volume in the columns. For some metals, mainly copper, chromium and mercury the dissolved organic matter affected the removal negatively. The chemical mechanisms causing the removal are specific adsorption to the surfaces of the materials, and for the blast-furnace slag probably precipitation of insoluble metal sulfides. / Starkt förorenat dagvatten som rinner av från exempelvis motorvägar, kan innehålla betydliga mängder tungmetaller som kan orsaka skada om de kommer ut i omgivande vattendrag. En billig metod för tungmetallavskiljning, som inte kräver så mycket underhåll, skulle kunna vara att använda reaktiva filtermaterial bestående av restprodukter eller andra mineraliska lågkostnadsmaterial. Reaktiva filter fungerar som metallavskiljare genom att de lösta metalljonerna binder till ytgrupper på filtermaterialen eller att svårlösliga utfällningar bildas. Förmågan att avskilja sju tungmetaller (Cr, Cd, Cu, Ni, Zn, Pb och Hg) ur dagvatten har undersökts för fyra mineraliska filtermaterial, kalciumoxiddopad masugnsslagg, järnoxidsand, olivin och nefelin. Studien inleddes med skakförsök där adsorptionens pH-beroende undersöktes. Försöken gjordes dels med dagvatten, dels med en referenslösning (10 mM NaNO3) med samma tungmetallkoncentration (ca 1μM). Detta gjordes för att studera effekter av löst organiskt material och andra ligander på adsorptionen. Därefter testades de material som uppvisat bäst resultat i skakförsöket i kolonnförsök, ett försök som mer efterliknar en praktisk tillämpning och där filtrets kapacitet kan studeras. Genom kemiska jämviktsberäkningar med programmet Visual MINTEQ var det möjligt att undersöka om bildningen av svårlösliga metallutfällningar bidrog till metallavskiljningen. Resultaten visar att slaggen var det effektivaste filtermaterialet och att detta har stor potential att användas för avskiljning av tungmetaller. Även järnoxidsanden fungerade tillfredsställande. De metaller som avskiljdes bäst var bly, kadmium och nickel, för vilka avskiljningen var > 90 % i kolonnförsöket efter en belastning motsvarande 300 gånger vattenmängden i kolonnerna. För vissa metaller, främst koppar, krom och kvicksilver, försämrades avskiljningen betydligt när löst organiskt material fanns närvarande. Mekanismerna som står för avskiljningen är till störst del adsorption till grupper på filtermaterialens ytor, men bildning av svårlösliga metallsulfider är också tänkbar för slaggen.
115

EFEITO DE RESERVATÓRIO DE APROVEITAMETO DE ÁGUA DA CHUVA SOBRE REDES DE DRENAGEM PLUVIAL / EFFECT OF RAINWATER HARVESTING RESERVOIRS OVER URBAN DRAINAGE NETWORKS

Hentges, Sara Ceron 28 August 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The urban growth and the disordered occupation of cities have increased the frequency and severity of flooding in urban areas, which occur mainly due to the modification on rainwater natural infiltration, as a result of soil imperviousness increase. The use of compensatory techniques (CT) for stormwater control has been encouraged through public polices, attempting to apply for sustainable solutions to mitigate the urbanization´s impact. An alternative already widespread in some Brazilian cities is the use of micro reservoirs (MR), which temporarily store volumes from impervious areas, and gradually emptying the water stored. Along this requirement, implementation of Rainwater Harvesting Reservoirs (RHR) to non-potable purposes is often encouraged in order to reduce the consumption of drinking water for less noble purposes, and to preserve the fountainheads. Some bibliographies suggest that in addition to these benefits, the RHR can be considered a CT also, once it stores the stormwater runoff, and therefore, in some cities where the MR is required, many buildings are already using the RHR to replace it. However, there are not many conclusive studies related to the real benefits and impacts that capturing rainwater and its use have on micro drainage networks, and specifically if such technique can be considered as a compensatory one. Thus, the main objective of this research was to evaluate whether RHR can be considered as an alternative to promote the quantitative stormwater control. For that, a comparative analysis was made between the impact that RHR use generates on micro drainage flows and networks, and the impact generated on a MR containing system. Such analysis was performed through a modeling of a urban watershed from Porto Alegre / RS, with 977 ha, 30.720 standard lots and around 70 km of micro drainage networks. The simulated MRs were designed according to the Decree No. 15.371/06 of the city of Porto Alegre, which aim to control the runoff at the source and it resulted in volumes of 3.13 m³ and 3.75 m³ for rainfall project with return period of 5 and 10 years (CP-CP-TR5 and TR10), respectively, answering to the allowable flow restriction at the lot outlet (VR = 0.624 L / s). The micro drainage networks were designed for both situations, with and without MRs, for CP-TR5 and CP-TR10. For sizing of the RHRs a continuous simulation of 12 years of precipitation data and demands series for non-potable uses data was performed, both with time step equal 5 minutes, resulting in volumes of 5.000, 10.000 and 15.000 liters due to the achieved service guarantee. These volumes of RHRs replaced the MRs and new modeling were performed considering observed rainfall data real from the continuum time series. It was found that the RHRs were not effective to maintain the VR at lots outlet, and the restriction value was exceeded for several times. For the simulated time seriess only the volume of 750 m³ would be appropriate to ensure only one offense within 10 years of simulation. That occurs because must have sufficient volume to store the expected drained volume, without spillage, regardless of the reservoir storage condition. However, if there is a very large storage capacity and demands are comparatively small, the reservoir does not empty. It was found, therefore, that exists an antagonism when trying to use the RHR for two functions: runoff control and water supply for non-potable purposes demand, since the attempt to ensure the fulfillment to the first function prevents the deployment of such large volumes. Overtopping of RHRs to 12 critical simulated events committed the microdrainage networks capacity, generating flooding in the streets along several drainage network ranges. Considering the same 12 critical events and MRs in lots were identified only four overflowing and lower overflows, which ended up committing a lower extent of drainage networks. Therefore, based on analysis of the continuous simulation with RHRs, it was found that it is not possible to consider it an equivalent technique to the MRs for storm water runoff control, unless the reservation volumes are extremely high, which would make its implementation on a few square meters lot impossible. / O crescimento urbano e a ocupação desordenada das cidades têm aumentado a frequência e a severidade das enchentes em áreas urbanas, que ocorrem, principalmente, devido à modificação nas condições naturais de infiltração das águas pluviais, decorrentes do aumento da impermeabilização do solo. Em busca de soluções sustentáveis para mitigar os impactos da urbanização, as políticas públicas vêm incentivando o uso de técnicas compensatórias (TC) para o controle do escoamento superficial. Uma alternativa já difundida em algumas cidades brasileiras é o uso de microrreservatório (MR), que armazena temporariamente os volumes oriundos do escoamento das áreas impermeáveis, esvaziando gradativamente a água armazenada. Paralelamente a essa exigência, a implementação de reservatórios para o aproveitamento da água da chuva (RAAC) com fins não potáveis vem sendo incentivada, com o intuito de reduzir o consumo de água tratada para fins menos nobres e preservar os mananciais. Algumas bibliografias sugerem que além desses benefícios, o RAAC pode ser considerado igualmente uma TC, já que armazenaria o escoamento pluvial, e por essa razão, em algumas cidades onde o MR é exigido, muitas edificações já estão utilizando o RAAC em substituição a este. No entanto, verifica-se uma falta de estudos conclusivos a respeito dos reais benefícios e impactos que a captação da água da chuva e seu aproveitamento têm sobre as redes de microdrenagem pluvial e, especificamente, se esta técnica pode ser considerada como compensatória. Assim, o principal objetivo desta pesquisa foi avaliar se os RAACs podem ser considerados como medidas para o controle quantitativo do escoamento pluvial. Para isso, foi realizada uma análise comparativa do impacto que a sua utilização gera sobre as vazões e redes de microdrenagem, com o impacto gerado em um sistema com MR. A análise foi realizada mediante modelagem matemática de uma bacia hidrográfica urbana da cidade de Porto Alegre/RS, com 977 ha, 30.720 lotes padrão e cerca de 70 km de redes de microdrenagem. Os MRs simulados foram dimensionados de acordo com o Decreto n° 15.371/06 da cidade de Porto Alegre para o controle do escoamento na fonte, resultando em volumes de 3,13 m³ e 3,75 m³, para chuvas de projeto com 5 e 10 anos de período de recorrência (CP-TR5 e CP-TR10), respectivamente, atendendo à vazão de restrição permissível na saída do lote (VR = 0,624 L/s). As redes de microdrenagem foram dimensionadas para as situações que contemplaram os MRs e para a situação sem os MRs, para CP-TR5 e CP-TR10. Para o dimensionamento dos RAACs foi realizada uma simulação contínua de 12 anos de dados de chuvas e série de demandas para fins não potáveis, ambas com intervalo de tempo de 5 minutos, tendo sido determinados os volumes de 5.000, 10.000 e 15.000 litros como os mais adequados para a edificação, em razão da garantia de atendimento atingida. Esses volumes de RAACs substituíram os MRs e novas modelagens foram realizadas considerando tanto eventos de projeto, como as chuvas reais da série contínua. Verificou-se que os RAACs não são eficientes na manutenção da VR na saída dos lotes, sendo que ao longo da série história simulada a mesma foi infringida várias vezes. Para a série histórica simulada apenas um volume de 750 m³ seria adequado para garantir apenas uma infração em 10 anos da simulação. Isso ocorre porque deve haver volume de espera suficiente para armazenar os volumes escoados, sem que haja vertimento, independentemente da condição de armazenamento do reservatório; no entanto, se existe uma capacidade de armazenamento muito grande, e as demandas são comparativamente pequenas, o reservatório não esvazia. Constatou-se, dessa forma, que existe um antagonismo quando se pretende utilizar o RAAC para as duas funções: controle de escoamento superficial e garantia de atendimento à demanda com fins não potáveis, visto que a tentativa de garantir o cumprimento da primeira função inviabiliza a implantação de volumes tão grandes. O extravasamento dos RAACs para 12 eventos críticos simulados comprometeu a capacidade das redes de microdrenagem, gerando armazenamento de água nas ruas ao longo de vários trechos. Considerando os mesmos 12 eventos críticos e os MRs nos lotes foram identificados apenas 4 extravasamentos e menores vazões extravasadas, o que acabou comprometendo uma menor extensão das redes de drenagem. Portanto, com base nas análises da simulação contínua com os RAACs, verificou-se que não é possível considerá-lo uma técnica equivalente aos MRs para o controle do escoamento pluvial, a menos que os volumes de reservação sejam extremamente elevados, o que tornaria impossível a sua implementação em um lote de poucos metros quadrados.
116

Análise da eficiência de métodos de controle de Enchentes na atenuação de picos de cheias utilizando o modelo computacional SWMM Storm Water managemente model / Analysis of the efficiency of flood control methods for the attenuation of peak flow using the SWMM - Storm water management model

SILVA, Karla Alcione da 31 August 2007 (has links)
Made available in DSpace on 2014-07-29T15:01:53Z (GMT). No. of bitstreams: 1 Dissertacao Karla Alcione da Silva.pdf: 1636555 bytes, checksum: d36dd50302f1e6a5b506033da1f1abb0 (MD5) Previous issue date: 2007-08-31 / This research presents an evaluation of the eficiency of four flood control measures applied to an urban basin in the city of Goiânia, State of Goiás, Brazil. Goiânia shows frequent flooding problems. The following factors have been identified as causes of the floodings: (1) significant number of impervious areas (2) lack of green areas, (3) insuficient capacity of the pipe network to convey the produced water volume. Small detention basins, infiltration trenches and the increase of permeable areas (30-50%) within parcels have been evaluated as flood control measures as well as the use of the Lago do Bosque dos Buritis as a detention basin. For this purpose, the Stormwater Management Model SWMM has been applied for evaluating 11 hypothetic management measures in the water basin. The later control measures were evaluated individually as combined. In determining the impervious area index of the studied area, field visits have been carried out, which showed high imperviousness. (86.16%). A synthetic rainfall time series, derived from the equation proposed by Costa e Brito (1999) with recurrence of 2 years, has been used in the simulations. Horton`s equation was applied to represent infiltration with parameters presented in Moura (2005). The scenario which combines the use of infiltration trenches and the increase of pervious areas to 50% has shown to be the best solution in reducing peak flow with 43% eficiency. On the other hand, the scenario using detention basins presented the smallest efficiency (3%). / O presente trabalho apresenta a avaliação da eficiência de quatro métodos de controle de enchentes em uma bacia urbana localizada na cidade de Goiânia, que apresenta graves problemas de inundação. Estes alagamentos devem-se a alguns fatores que foram levantados, tais como: muitas áreas impermeabilizadas, poucas áreas verdes e rede com dimensões pequenas e insuficientes para o escoamento de todo o volume produzido. Foram analisadas a implantação de microservatórios de detenção, trincheira de infiltração, o aumento da área permeável no interior do lotes (de 30% e 50%) e o uso dos lagos do Bosque dos Buritis como dispositivo de controle. Para tanto, procederam-se simulações no modelo computacional SWMM Storm Water Management Model em que foram avaliados 11 cenários hipotéticos na bacia, que consistiram na aplicação dos dispositivos de forma individual e em conjunto. Para a determinação do índice de impermeabilização da área estudada foi necessário realizar um levantamento em uma área amostra, o qual demonstrou uma média de 86.16% de impermeabilização em cada lote. A precipitação utilizada foi uma série sintética, determinada por meio da equação de chuva desenvolvida por Costa e Brito (1999) com tempo de recorrência adotado de 2 anos. Para representar a infiltração, optou-se por trabalhar com a equação de infiltração de Horton, segundo os parâmetros de Moura (2005). O cenário simulado com a implantação de trincheira de infiltração e o aumento da área permeável em 50% apresentou aproximadamente 43% de eficiência na redução da vazão de pico, indicando que essa poderia ser a melhor solução para o problema analisado, enquanto que o cenário com microreservatórios apresentou a menor eficiência, aproximadamente 3%.
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Předčištění odpadních vod na stokové síti / Wastewater pretreatment at sewerage network

Doskočilová, Denisa January 2015 (has links)
ABSTARCT The aim of this thesis is to treat the problem of wastewater pretreatment on the sewer network with a focus on storm water overflow and their impact on waterways with regard to The Methodological Manual for Assessment of storm water overflow within uniform sewerage systems in urban areas. This work describes the legislation relating to storm water overflow and includes comparison with other countries. Furthermore, there is processed the outline of objects and equipment which can be used for wastewater pre-treatment in the sewer network. In the practical part of the thesis there is designed a new solution for the mobile spillway edge of the storm water overflow OK2A, which is located within the sewer network in Brno. In the practical part of the paper there is depicted the project documentation of newly designed equipment and objects. Water management companies, design offices, students and the general public can use this thesis as an inspiration.
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The Effectiveness of a Stormwater Detention Pond in Enhancing Water Quality

Droppo, Ian Gerald 04 1900 (has links)
This research paper fulfills the requirements of Geography 4C6. / This paper is an introductory study on the ability of a detention pond to reduce pollutant loading to a receiving water body. Three forms of water pollution are analysed in this study, trace metal (V, Ti and Mn in the water and on suspended solids and bottom sediments), organic and bacterial (bacterial indicators of fecal coliform and fecal streptococci are utilized) pollutants. Each pollutant type requires a different form of analysis to obtain concentrations for targeted pollutants. V, Ti and Mn concentrations were obtained from Instrumental Neutron Activation Analysis (INAA), organic concentrations were acquired by Electron Capture Gas Chromatography (ECGC) and bacterial concentrations were obtained from various laboratory techniques performed by technicians in the Microbiology Lab at McMaster University and in the Provincial Health Laboratories in Hamilton, Ontario. Suspended solid concentration are also analysed to determine the pond's effectiveness in reducing suspended solids load and thus the pollutants they carry. The Storm Water Management Model was used to estimate total pollutant loading into the pond via a combined sewer overflow (CSO). The pollutant concentrations obtained were analysed spatially through the sampling network and temporally between sampled dry and wet weather periods. The result of this study has led to the disturbing conclusion that the detention pond appears to have little or no effect on enhancing water quality. / Thesis / Bachelor of Science (BSc)
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Modelling the Hydraulic Response of Permeable Pavements: a Numerical and Experimental Approach for Model Comparison and Sensitivity Analysis to Design Parameters

Madrazo Uribeetxebarria, Eneko 04 September 2023 (has links)
Tesis por compendio / [ES] Los Pavimentos Permeables (PP) son una técnica de los denominados Sistemas Urbanos de Drenaje Sostenible (SUDS). A diferencia de otras técnicas de este tipo, proporciona una superficie dura transitable a la vez que gestiona las aguas pluviales superficiales, siendo sus propiedades hidráulicas fundamentales para su rendimiento como SUDS. Esta tesis explora el rendimiento hidráulico de los PP, basándose en el modelo hidrológico-hidráulico de PP proporcionado en el ampliamente utilizado Storm Water Management Model (SWMM). La tesis se presenta en un formato de tres artículos. Así, tras una aproximación a la pregunta general de investigación dada en el primer capítulo introductorio, el segundo capítulo del documento analiza qué parámetros son los más influyentes y cuáles son despreciables en el modelo, proporcionando un análisis de sensibilidad general. El siguiente capítulo explora la relación entre el modelo de PP de SWMM y el modelo de número de curva (CN), ampliamente utilizado, en lo que respecta a la escorrentía deducida por ambos modelos en función de la permeabilidad del pavimento. En el cuarto capítulo se analiza la respuesta del PP en condiciones experimentales controladas y se compara con el modelo de PP dado en SWMM. Tras una discusión general de los resultados en el quinto capítulo, se ofrecen unas conclusiones generales en el último. La tesis profundiza en el conocimiento del comportamiento hidráulico de los PP para ayudar a profesionales e investigadores en su caracterización. / [CA] Els Paviments Permeables (PP) són una tècnica dels denominats Sistemes Urbans de Drenatge Sostenible (SUDS). A diferència d'altres tècniques d'aquest tipus, proporciona una superfície dura transitable alhora que gestiona les aigües pluvials superficials, sent les seues propietats hidràuliques fonamentals per al seu rendiment com SUDS. Aquesta tesi explora el rendiment hidràulic dels PP, basant-se en el model hidrològic-hidràulic de PP proporcionat en l'àmpliament utilitzat Storm Water Management Model (SWMM). La tesi es presenta en un format de tres articles. Així, després d'una aproximació a la pregunta general d'investigació donada en el primer capítol introductori, el segon capítol del document analitza quins paràmetres són els més influents i quins són menyspreables en el model, proporcionant una anàlisi de sensibilitat general. El següent capítol explora la relació entre el model de PP de SWMM i el model de número de corba (CN), àmpliament utilitzat, pel que fa a l'escolament deduït per tots dos models en funció de la variable permeabilitat del paviment. En el quart capítol s'analitza la resposta del PP en condicions experimentals controlades i es compara amb el model de PP donat en SWMM. Després d'una discussió general dels resultats en el cinqué capítol, s'ofereixen unes conclusions generals en l'últim. La tesi aprofundix en el coneixement del comportament hidràulic dels PP per a ajudar a professionals i investigadors en la seua caracterització. / [EN] Permeable Pavements (PP) are a Sustainable Urban Drainage System (SUDS) technique. Unlike other such techniques, it provides a transitable hard surface while managing surface stormwater, being its hydraulic properties fundamental for its performance as a SUDS. This dissertation explores the hydraulic performance of PPs, based on the hydrologic-hydraulic model of PP provided in the widely used Storm Water Management Model (SWMM). The dissertation is presented in a \textit{three-paper} format. Accordingly, after an approach to the general research question given in the first introductory chapter, the second chapter of the document analyses which parameters are the most influential and which are negligible in the model by providing a general sensitivity analysis. The next chapter explores the relation between the PP model from SWMM and the widely used Curve Number (CN) model regarding runoff generated by both models and examines the relationship between both approaches based on the pavement permeability variable. The fourth chapter analyses the PP response under controlled experimental conditions and compares it with the PP model given in SWMM. After a general discussion of the results in the fifth chapter, general conclusions are given in the last chapter. The dissertation deepens the understanding of the hydraulic behaviour of PPs to help practitioners and researchers with its characterisation. / Madrazo Uribeetxebarria, E. (2023). Modelling the Hydraulic Response of Permeable Pavements: a Numerical and Experimental Approach for Model Comparison and Sensitivity Analysis to Design Parameters [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/196085 / Compendio
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Detention-based Green/Gray Infrastructure Framework to Control Combined Sewer Overflows

Mancipe Muñoz, Nestor Alonso 19 October 2015 (has links)
No description available.

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