In this thesis, a semi-permeable lining system was proposed to upgrade arctic wastewater stabilization ponds, acting as a biofilter. Although commonplace at lower latitudes, the effects of cold temperatures and short-duration summers on biofilter performance are inadequately studied. The goal of this research was to study the hydraulic and treatment performance of geotextile substrate biofilters under arctic conditions. Filtration experiments were conducted in a laboratory environment. Municipal wastewater was passed through columns containing nonwoven geotextiles over 10 cm of gravel. Three experimental trails were conducted at either 10? or 2?, each lasting 12 weeks. Weekly samples taken before and after filtration were analyzed for various water quality parameters. Hydraulic conductivity was monitored using weekly constant head permeameter tests. Results showed that biomat accumulation is possible on geotextile material over 12 week period. Significant removal of TSS and BOD5 was observed, along with a 1-log reduction in hydraulic conductivity.

Geossintéticos são materiais cada vez mais aplicados em aterros sanitários, cumprindo diferentes funções como barreiras para líquidos e gases. Na função de filtração, o uso destes materiais não está consagrado, principalmente, em função da possível colmatação total ou parcial dos geotêxteis por ação de microrganismos, a chamada colmatação biológica. Neste contexto, o presente trabalho visa avaliar a colmatação de geotêxteis tecidos e não tecidos submetidos ao fluxo de lixiviado de aterro sanitário. Foram utilizados três geotêxteis não tecidos de gramatura 200 g/m², sendo um de filamento contínuo de poliéster (PET) e dois de fibra curta, porém fabricados com polímeros diferentes poliéster e polipropileno (PET e PP) e um geotêxtil tecido de polipropileno, com gramatura 400 g/m². Para avaliar a colmatação dos geotêxteis montaram-se ensaios de permeabilidade de longa duração em que se mediu a condutividade hidráulica ao longo do tempo. Após os ensaios de permeabilidade, realizou-se microscopia eletrônica de varredura para avaliar o fechamento dos poros dos geotêxteis, além de avaliar o crescimento bacteriano ocorrido no interior do geotêxtil. Os resultados obtidos permitem constatar significativa redução da condutividade hidráulica dos materiais após o período de 30 dias de ensaios, onde notou-se a predominância do processo de cegamento. / Geosynthetics materials have been intensively used in landfills in different functions as liquid and gas barriers. As filters, geosynthetics are not completely accepted in designs, since total or partial geotextile clogging can occur for biotic deposition (or impregnation), usually named biological clogging. This work evaluates the clogging on nonwoven and woven geotextiles under leachate flow for landfill application. For this purpose, nonwoven geotextiles with short and long polyester filaments and mass per unit area of 200 g/m² were used, as well as polypropylene and polyester nonwoven geotextiles with mass per unit area of 400 g/m². Cross-plane permeability tests were periodically conducted in geotextiles samples which were under long term leachate flow. After each permeability test, scanning electron microscopy (SEM) was conducted to evaluate the source of pore geotextile clogging, as well as the bacteria growing into the geotextile matrix. Results have shown a significantly reduction on hydraulic conductivity of geotextile filters after 30 days of leachate flow, which was motivated by blinding process.

The effectiveness of temporary flood protection is highly variable depending on the location, application, and the nature of flood events. This thesis evaluates sand-filled geotextile containers used as flood protection products within a framework of standardized tests. Specifically, Syn-Tex Wave Breakers and Super Sandbags are tested in both laboratory and field settings to quantify seepage rates, stability and durability. This allows informed decisions to be made regarding appropriate applications for each temporary flood protection product, and identifies areas for product improvement and development. The products tested performed well over the range of loading conditions applied. Large sand-filled geotextiles would be well-suited for situations where stakeholders have a low tolerance for risk, and there is adequate site access for the construction equipment required for installation. An ideal installation would be a long, relatively straight stretch where vertical product/wall and product/product interfaces can be minimized.

Geossintéticos são materiais cada vez mais aplicados em aterros sanitários, cumprindo diferentes funções como barreiras para líquidos e gases. Na função de filtração, o uso destes materiais não está consagrado, principalmente, em função da possível colmatação total ou parcial dos geotêxteis por ação de microrganismos, a chamada colmatação biológica. Neste contexto, o presente trabalho visa avaliar a colmatação de geotêxteis tecidos e não tecidos submetidos ao fluxo de lixiviado de aterro sanitário. Foram utilizados três geotêxteis não tecidos de gramatura 200 g/m², sendo um de filamento contínuo de poliéster (PET) e dois de fibra curta, porém fabricados com polímeros diferentes poliéster e polipropileno (PET e PP) e um geotêxtil tecido de polipropileno, com gramatura 400 g/m². Para avaliar a colmatação dos geotêxteis montaram-se ensaios de permeabilidade de longa duração em que se mediu a condutividade hidráulica ao longo do tempo. Após os ensaios de permeabilidade, realizou-se microscopia eletrônica de varredura para avaliar o fechamento dos poros dos geotêxteis, além de avaliar o crescimento bacteriano ocorrido no interior do geotêxtil. Os resultados obtidos permitem constatar significativa redução da condutividade hidráulica dos materiais após o período de 30 dias de ensaios, onde notou-se a predominância do processo de cegamento. / Geosynthetics materials have been intensively used in landfills in different functions as liquid and gas barriers. As filters, geosynthetics are not completely accepted in designs, since total or partial geotextile clogging can occur for biotic deposition (or impregnation), usually named biological clogging. This work evaluates the clogging on nonwoven and woven geotextiles under leachate flow for landfill application. For this purpose, nonwoven geotextiles with short and long polyester filaments and mass per unit area of 200 g/m² were used, as well as polypropylene and polyester nonwoven geotextiles with mass per unit area of 400 g/m². Cross-plane permeability tests were periodically conducted in geotextiles samples which were under long term leachate flow. After each permeability test, scanning electron microscopy (SEM) was conducted to evaluate the source of pore geotextile clogging, as well as the bacteria growing into the geotextile matrix. Results have shown a significantly reduction on hydraulic conductivity of geotextile filters after 30 days of leachate flow, which was motivated by blinding process.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-04-03T15:06:37Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO - CLAUDENICE - VERSÃO FINAL com ficha.pdf: 2029551 bytes, checksum: 88a2e3ec67def98ebd9888865b61ecd4 (MD5) / Made available in DSpace on 2017-04-03T15:06:37Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO - CLAUDENICE - VERSÃO FINAL com ficha.pdf: 2029551 bytes, checksum: 88a2e3ec67def98ebd9888865b61ecd4 (MD5) Previous issue date: 2016-08-19 / O sistema de tratamento de águas residuais ou de esgoto é destinado à remoção de poluentes que se encontram em fase dissolvida ou particulada. O lodo gerado após o tratamento desses resíduos é um problema no âmbito de saneamento das cidades, pois não há evidências de tratamento eficiente. Este trabalho avaliou os metais presentes no lodo da ETE Mangueira após dois tipos de tratamento, e comparou os resultados dos metais da massa sólida resultante com a legislação vigente para utilização na agricultura. O primeiro tratamento foi utilizado coagulante e o segundo sem coagulante. As amostras foram coletadas na válvula de descarga do lodo, situada na base do reator anaeróbio, e enviadas para laboratório. A cada semana era realizada uma nova coleta e o bag de geotêxtil era alimentado para drenagem do lodo. O período de amostragem foi de 3 (três) meses. Foram realizadas análises para caracterização do lodo antes, durante e depois do lodo presente nos bags, como também do líquido drenado. Após enchimento dos bags, foram retirados 12 (doze) pontos amostrais, e misturadas para obtenção de 3 (três) amostras de 200g para análise de metais e de sólidos. Os resultados indicaram que o uso do Bag de geotêxtil para remoção de poluentes é bastante eficiente, visto que a concentração de metais do lodo bruto em comparação com o lodo tratado sem uso do polímero foi de 98% de Fe, 98% de Cu, 93% de Pb, 89% de Mn, 100% de Zn e 98% de Al. Já com a adição do polímero os resultados mostraram, 99% de Fe, 98% de Cu, 93% de Pb, 89% de Mn, 100% de Zn e 99% de Al. Os resultados dos metais presentes na massa sólida quando comparados com o CONAMA 375/06 e a CETESB/EUA, indicaram que o metal zinco foi avaliado, resultando em uma concentração de 177,72 mg/kg e atendeu aos requisitos da legislação que são 2.800mg/kg e 7.500mg/kg respectivamente. E os sólidos avaliados, indicaram que a massa em estudo atende aos requisitos do CONAMA 375/06 que recomenda uma relação de 0,7 entre os Sólidos Voláteis e os Sólidos Totais Voláteis. Obtendo assim para o drenado sem coagulante e com o coagulante, 0,62 e 0,57 respectivamente. Observa se que o uso do polímero foi pouco significativo, sendo o uso do geotêxtil eficiente na remoção de partículas sólidas provenientes de lodo de ETE. / The sewage or waste water treatment system is intended for removing pollutants which are dissolved or particulate phase. The sludge generated after treatment of this waste is a problem in sanitation context of town because there is no effective treatment of evidence. This study evaluated the metals present in the sludge from ETE hose after two types of treatment, and compared the results of the resulting solid mass of metal with current legislation for use in agriculture. The first treatment was used without coagulant and the second coagulant. The samples were collected in the sludge discharge valve at the base of the anaerobic reactor and sent to the laboratory. Each week was held a new collection and bag geotextile was fed to sludge drainage. The sampling period was 3 (three) months. sludge characterization for analyzes were performed before, during and after this sludge in bags, as well as the drainage. After filling the bags were removed from twelve (12) sampling points, and mixed to obtain three (3) samples of 200g for analysis of metals and solids. The results indicated that use of the bag geotextile for removing pollutants is very efficient, since the concentration of the raw sludge metals compared to the sludge treated without use of polymer was 98% Fe, 98% Cu, 93 % Pb, 89% Mn 100% Zn and 98% Al. However, with the addition of the polymer results showed 99% Fe, 98% Cu 93% Pb, 89% of Mn, 100 % Zn and 99% Al. the results of the metals present in the solid mass when compared to CONAMA and Cetesb 375/06 / USA, showed that zinc metal was measured, resulting in a concentration of 177.72 mg / kg and met the requirements of the legislation that are 2.800mg / kg and 7.500mg / kg respectively. And this solid indicated that the mass CONAMA 375/06 study meets the requirements that recommends a ratio between 0.7 Volatile Solids and Total Volatile Solids. So getting to the drained without coagulant and the coagulant, 0.62 and 0.57 respectively. It observed that the use of polymer was negligible, and the use of geotextile effective in removing solid particles from the WWTP sludge.

The three-dimensional behavior of geotextile tubes is studied using finite element modeling. Two initial shapes are investigated, one with a flat length-to-width ratio of 2:1 and the other with a flat length-to-width ratio of 5:1. The tubes are modeled resting on elastic foundations. For each initial shape, the elastic foundation is modeled using two different stiffnesses; one allows a minimum amount of "sinking" into the foundation and the other allows a considerable amount. The weight of the geotextile is included. Hydrostatic pressure is applied internally to each initially flat tube to model the pumped slurry. The shape of the tube is studied along with the contact region between the tube and its foundation, the stresses which develop in the geotextile along the planes of symmetry, and the relationship between the height of the tube and the amount of applied hydrostatic pressure. / Master of Science

Įrengiant automobilių kelio ar gatvės dangas ant žemės sankasos bei vėliau jas eksploatuojant dėl nuolatos pasikartojančių statinių bei dinaminių transporto priemonių apkrovų gali prasidėti žemės sankasos grunto bei apsauginio šalčiui atsparaus sluoksnio medžiagų sąmaiša. Analogiškas procesas gali vykti ir tarp apsauginio šalčiui atsparaus sluoksnio bei dangos pagrindo medžiagų. Ilgainiui kelio ar gatvės konstrukcijos sluoksnių medžiagų tarpusavio sąmaiša mažina dangos stiprį bei tvarumą. Siekiant išvengti atskirų konstrukcijos sluoksnių mineralinių medžiagų tarpusavio susimaišymo, tiesiant kelius ar gatves bei juos eksploatuojant, pastaruosius 15 metų pasaulyje plačiai taikomi geotekstilės tarpsluoksniai. Jungtinių Amerikos Valstijų mokslininkai geotekstiles parinkti rekomenduoja naudoti skaičiavimus pagal formules, tačiau jos tinka tik keliams be asfaltbetonio dangos. Kitas geotekstilių taikymo būdas – atskirų šalių sukurtos normos bei rekomendacijos. Europoje nėra vieningų norminių dokumentų, reglamentuojančių geotekstilių naudojimą automobilių kelių bei gatvių konstrukcijos sluoksniams atskirti. Tai galima pagrįsti tuo, kad Europos valstybėse yra skirtingos klimatinės bei geologinės sąlygos. Taigi kiekviena ar keletas valstybių, kurioms pagal jų sąlygas aktualu kelio konstrukcijos sluoksnius atskirti geotekstilėmis, turi savo normas ar rekomendacijas. Lietuvoje geosintetinės medžiagos tiesiant ir rekonstruojant automobilių kelius bei miestų gatves naudojamos tik pastarąjį... [toliau žr. visą tekstą] / During construction of road or street pavement structure and its operation the continuous static and dynamic vehicle loads may cause the intermixing of the subgrade soil with the frost blanket course. Analogical process could happen between the frost blanket course and the sub-base constructed from the large particles of aggregate. Eventually, the intermixed materials of the different structural layers of road or street can have the impact on the strength and durability of the whole structure. In order to prevent the aggregates of different structural layers from becoming intermixed during road or street construction or in the phase of operation the geotextile inter-layers have been world-widely used in the recent 15 years. Method for selecting geotextiles – specifications and recommendations of different countries. At present there are no generally accepted European specifications regulating the selection of geotextiles intended for separating road or street pavement layers. The reason is that different European countries have different climatic and geological conditions. Thus, each or several countries, where these conditions require separation of pavement structural layers by the geotextile, have their own normative documents or recommendations. Lithuania has only been using geotextiles in road and street construction and reconstruction during the last decade. In 1998 Lithuanian Road Administration adopted the temporary regulations on Using Geotextiles and Geogrids for... [to full text]

Doctor of Philosophy / Department of Civil Engineering / Mustaque Hossain / Geotextiles have been widely promoted for pavement structure over the past 30 years. However, there is a lack of well-instrumented, full-scale experiments to investigate the effect of geotextile reinforcement on the pavement design. In this study, full–scale accelerated tests were conducted on eight lanes of pavement test sections. Six out of these eight sections had granular bases reinforced with different types of woven geotextiles. The reinforced base sections and the control sections (with unreinforced base) were paved with Superpave hot-mix asphalt. Base and subgrade materials were the same for all sections while the test sections had different asphalt and base layer thicknesses. Each section was instrumented with two pressure cells on top of the subgrade, six strain gages on the geotextile body, six H-bar strain gages at the bottom of the asphalt layer, two thermocouples and one Time Domain Reflectometer (TDR) sensor. The sections were loaded to 250,000 to 500,000 repetitions of an 80-kN single axle load of the accelerated pavement testing machine. The mechanistic response of each section was monitored and analyzed at selected number of wheel passes. Results indicate that properly selected and designed geotextile-reinforced bases improve pavement performance in term of rutting and reduced pressure at the top of the subgrade. Finite element (FE) models were developed and verified using results from the full-scale accelerated pavement tests. The calibrated model was used to investigate the effects of geotextile properties on the pavement responses. FE analysis shows that benefits of reinforcement are more evident when stiffer geotextile is used.

ENGLISH ABSTRACT: Current understanding of the hydraulic stability of a stacked geotextile tube structure under wave attack is limited. Failure mechanisms that lead to instability are complicated and there is, as yet, no generic approved design method. 2D physical modelling in the large wave/current flume of the Stellenbosch University was done to test various set-up and hydraulic conditions to determine the hydraulic stability of a stacked geotextile tube structure against wave attack. Sixty-five test runs of approximately 1,000 waves each were run. Modelling was done on two different scales that had good similitude, despite the fact that the same geotextile and fill material were used in both. The results provided by the physical modelling gave wave conditions larger than anticipated for hydraulic stability. It was found that the term ―failure‖ was too loosely defined in most cases and that, depending on the definition of structure failure the severity of the wave conditions at failure increased substantially. Sliding was found to be the key failure mechanism for a structure constructed from stacked, 80% sand filled, geotextile tubes. The crest tube receives the most severe loading and is the critical tube in the structure. Structures with double tube crests were found to be negligibly more stable than structures with single tube crests, but reduce energy transmission to the leeside of the structure. Impact loading of the structure combined with wave transmission over the structure explained the wave force on the crest tube of the structure. A modified Goda (1974) method incorporating a wave reduction factor for wave transmission and an angle descriptive of the crest tube position were used. The descriptive angle was derived from results obtained from the physical modelling. The use of this method provides results that correlate well with those found in the physical modelling and with results obtained in previous research. The method has the additional advantage that it is less constrained by limitations for application than those of previous studies / AFRIKAANSE OPSOMMING: Die begrip van die hidroliese stabiliteit van ‘n struktuur gebou uit gepakte geotekstielsandbuise teen golf aanval, is tans beperk. Faal meganismes wat lei tot die onstabiliteit van ‘n struktuur is ingewikkeld en daar is geen generiese aanvaarde ontwerp metode tans in gebruik nie. 2D fisiesemodellering is in die groot golfkanaal van die Universiteit Stellenbosch uitgevoer. ‘n Verskeidenheid van struktuur-uitlegte en hidroliese toestande is getoets om die hidroliese stabiliteit van die struktuur teen golf aanval te bepaal. ‘n Totaal van 65 toetse van ongeveer 1,000 golwe elk is voltooi. Modellering is op twee verskillende skale gedoen, wat goed vergelyk het ten spyte van die feit dat dieselfde geotekstiel en vul materiaal in albei gebruik is. Resultate verkry vanaf die fisiese modellering het groter as verwagte golftoestande vir hidroliese stabiliteit gegee. Dit is gevind dat die definisie van faal (mislukking) in die meeste gevalle swak beskryf is en dat, afhangende van wat as faal van die struktuur beskou word, die golftoestande aansienlik beïnvloed word. Die skuif van die buise is die hoof faal meganisme vir ‘n gepakte geotekstielbuis-struktuur met ‘n vulpersentasie van 80%. Die buis op die kruin van die struktuur word die swaarste belas en is die kritiese buis in die struktuur. Strukture met dubbel buis kruine is onbeduidend meer stabiel as dié met slegs ‘n enkele buis as kruin. Die energie wat na die lysy van die struktuur oorgedra word, is egter beduidend minder. Impak belasting van die struktuur gekombineer met golf-transmissie oor die struktuur, verduidelik die stabiliteit van die buis op die kruin van die struktuur. ‘n Gemodifiseerde Goda (1974) metode met ‘n golfverminderigs faktor word gebruik om golf-transmissie oor die struktuur te akkommodeer, saam met ‘n hoek wat beskrywend is van die posisie van die kruin buis. Die beskrywende hoek is afgelei uit resultate verkry uit die fisiesemodellering. Hierdie metode gee resultate wat goed korreleer met dié verskaf deur die fisiese modellering en die resultate van vorige navorsing oor geotekstielbuis stabiliteit. Die metode het ‗n bykomende voordeel deurdat dit minder begrens is deur beperkings m.b.t. toepassing as die van vorige studies.

Thesis (MScEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Geotextiles perform a number of functions in various applications in civil engineering practise. It is often cost effective and more environmentally friendly versus conventional construction methods. One of the main functions of a geotextile is filtration whereby the geotextile is expected to hold back the soil particles and simultaneously has to allow sufficient water to pass through it. Soils are all different and can be problematic when it comes to designing geotextile filters. One such problematic soil is encountered in KwaZulu- Natal, situated along the east coast of South Africa. The Berea sand is problematic as it can highly variable in its engineering properties over a small area. Geotextiles are becoming more and more common practice in South Africa and little is known about the filtration performance of commercially available geotextiles in conjunction with Berea sand. Local guidelines that are available are out of date and do not provide enough information to assist design engineers in decision making. Many international guidelines are available and it is difficult to choose which one is best suited to Berea sands. This primary objective of this study is to investigate the filtration performance of four variants of commercially available geotextiles and three variants of Berea sand. The applicability of some of the international filter design criteria will also be assessed. The soil to geotextile compatibility testing was carried out as per ASTM D5101 (2006) - Standard Test Method for Measuring the Soil-Geotextile System Clogging Potential by the Gradient Ratio. In total 12 permutations were executed. The results showed that only 5 test permutations met the gradient ratio and permeability criteria. The test results also conclude that the permeability is just as important as the gradient ratio. Thick geotextiles should be considered when used as filters in Berea sands. The available international geotextile filter design criteria were assessed and all showed poor correlation between laboratory results and suggested criteria. Designing geotextile filters in conjunction with Berea reds is challenging and it is recommended that design engineers perform laboratory performance testing in conjunction with their designs. / AFRIKAANSE OPSOMMING: Geotekstiele verrig vir 'n aantal funksies in verskeie programme in die siviele ingenieurswese praktyk. Dit is dikwels meer koste-effektief en omgewingsvriendelik, teenoor konvensionele konstruksie metodes. Een van die belangrikste funksies van 'n geotekstiel is filtrasie, waardeur van die geotekstiel verwag word om van die grond terug te hou, en gelyktydig genoeg water daardeur te laat vloei. Grond verskil en dit kan problematies wees wanneer dit kom by die ontwerp van geotekstiel filters. Een so ‘n problematiese grond kom voor in KwaZulu-Natal, geleë langs die ooskus van Suid-Afrika. (Die) Berea sand is problematies, want dit verander geweldig baie ten opsigte van ingenieurseienskappe oor 'n redelike klein area. Gebruik van geotekstiele word al hoe meer ‘n algemene praktyk in Suid- Afrika, terwyl min bekend is oor die filtrasie prestasie van kommersieel beskikbare geotekstiele in samewerking met Berea sand. Plaaslike riglyne wat beskikbaar is, is verouderd en onvoldoende inligting is beskikbaar aan ontwerpingenieurs vir besluitneming . Baie internasionale riglyne is beskikbaar en dit is moeilik om te besluit watter een die beste van toepassing is vir Berea sand. Die doel van hierdie studie is om die filtrasie prestasie van vier modelle van kommersieël beskikbare geotekstiele en voorbeelde van drie soorte Berea sand te ondersoek. Die toepaslikheid van 'n paar van die internasionale filter ontwerp kriteria sal ook beoordeel word. Die toetsing van grondverenigbaarheid met geotekstiel is uitgevoer soos aangedui in ASTM D5101 (2006 ) – Standaard Toets Metode vir die meet van die grond-Geotekstiel verstopping potensiëel deur die gradient verhouding. In totaal is 12 permutasies uitgevoer. Die resultate het getoon dat slegs 5 toetspermutasies beide gradiënt verhouding en permeabiliteit kriteria bevredig het. Dikker geotekstiele word ook aanbeveel vir gebruik as filters in Berea sand. Van die toets resultate kan ook afgelei word dat die permeabiliteit net so belangrik soos die gradiënt verhouding is. Beskikbare internasionalegeotekstiel filter ontwerp kriteria is nagegaan en al die metodes het swak korrelasie tussen laboratorium resultate en die voorgestelde kriteria getoon. Om geotekstiel filters in samewerking met Berea Reds te ontwerp is 'n uitdaging en dit word aanbeveel dat ontwerpingenieurs laboratorium prestasietoetsing in samewerking met hul ontwerpe uitvoer.