No description available.

La presente tesis tiene como principal objetivo la implementación de un laboratorio de geotextiles acreditado (no fabricante) que realice los ensayos físicos, mecánicos e hidráulicos normados, para que, de esta manera, se pueda asegurar la calidad y cumplimiento según la norma ASTM de estos geosintéticos. Para ello, es necesario definir y comparar las normas involucradas en el uso de los geotextiles para las aplicaciones ingenieriles. Existen dos normas que detallan esta información: la norma AASHTO M288 y la normativa peruana EG-2013. Una vez comparadas ambas normas, se seleccionan los ensayos que verifican las propiedades de los geotextiles para proceder a la postulación a la acreditación internacional GAI-LAP, la cual es regulada por el Instituto de Geosintéticos. También, en el presente documento se desarrolla un ejemplo de diseño comparativo entre una solución tradicional versus un diseño con el uso de geotextiles no tejidos para la función de separación de una vía pavimentada. Se concluye que el compendio de una normativa peruana que abarque el diseño con geotextiles por especificación y función es necesaria, sobre todo, en los sectores viales, minería y geotecnia. Además, con el ejemplo de diseño descrito, se demuestra que con el uso de geotextiles no tejidos en la vía pavimentada se reducen espesores de material granular y se logran ahorros económicos de por lo menos el 2%. Finalmente, la propuesta de implementación de un laboratorio de geotextiles en la Pontificia Universidad Católica del Perú debe ir acompañada de la acreditación GAI-LAP, ya que de esta manera se garantiza la competencia técnica y confiabilidad de los organismos que postulan a la evaluación.

Este trabalho apresenta resultados de ensaios de fluência confinada e não-confinada de geotêxteis não-tecidos agulhados. Algumas dificuldades encontradas durante o desenvolvimento dos equipamentos utilizados para realizar esses ensaios em laboratório são também apresentadas e discutidas. A etapa de investigação sem confinamento envolveu a utilização de geotêxteis de poliéster e de polipropileno. Os resultados confirmaram o grande potencial desses materiais em apresentar fluência assim como a maior susceptibilidade dos geotêxteis de polipropileno. No caso de ensaios com confinamento, tentativas de se tracionar um geotêxtil de polipropileno entre duas camadas de solo revelaram grandes dificuldades para manter a carga aplicada constante ao longo do corpo de prova, em virtude da existência de atrito nas interfaces solo-geotêxtil. Ensaios alternativos retirando-se o solo e envolvendo-se o geotêxtil em uma membrana de látex lubrificada apresentaram bons resultados, comprovando a redução da fluência em relação aos ensaios não confinados e denotando tratar-se de uma solução viável para investigar o real papel do confinamento na fluência dos geotêxteis. / This work presents results of confined and unconfined creep tests on nonwoven needle punched geotextiles. Withdraws found during the equipment development used to perform these tests are also highlighted and discussed. The unconfined tests encompassed the use of polyester and polypropylene geotextiles. Results confirm that these materials have a great potential to creep, being the polypropylene geotextiles the material with the greatest susceptibility. The confined tests where geotextile was placed between two soil layers revealed difficulties in keeping the applied load constant throughout the specimen due to soil-geotextile interface friction. Alternative tests performed without the soil and embedding the geotextile in a lubricated latex membrane showed good results, proving the decrease of creep in relation to unconfined tests. Thus, one can conclude that this is a viable solution towards the investigation of the real role that confinement plays in geotextile creep.

Thesis--Auburn University, 2008. / Abstract. Vita. Includes bibliographic references (p.65-67).

No description available.

Composting trials were undertaken to study the feasibility of using crucifer or carrot residues with straw or sawdust for composting. Compost temperature and moisture were monitored regularly, and compost samples were analyzed for physico-chemical characteristics at the beginning in the fall, before turning in spring, and at the end of each composting cycle. A geotextile cover was tested. Compost leachate volumes were measured throughout the two composting cycles. In addition, the leachate was submitted to phytotoxicity tests and physico-chemical analyses. Selected phytopathogens were introduced in the compost in order to assess their potential for survival during the composting process. Three pathogens having resistant survival structures were included: Plasmodiophora brassicae, Fusarium oxysporum f.sp. cucumerinum , and Sclerotinia sclerotiorum. Greenhouse growth trials were performed with compost-enriched media and a commercial mix. (Abstract shortened by UMI.)

Three systems for filtering polluted river water for use in subsurface irrigation have been designed, operated and evaluated. One system consisted of filtering the water through filter basins covered with grass. The second system used geotextiles in filter basins. The third system consisted of flooding a section of a field. In this system, the water was filtered as it moved through the soil towards the subsurface drainage/irrigation drain pipes. / It was found that grass filter basins are very efficient in removing sediment from river water. Grass filter basins having drain pipes placed in trenches 30 cm wide backfilled with sand gave the best results. More than 90% of sediments were removed from the river water. From the outflow measurements, it was found that less than 0.2% of the field to be irrigated needs to be devoted to the filtration system. / Important filter design parameters, namely filtration rates per unit area of filter basin and per unit length of filter trench and drain pipe, were determined. / Due to the fast clogging of the geotextile, filtration of river water through basins covered with geotextile was found to be impractical and expensive, as compared to filtration using water tolerant grasses as a basin cover. / Flooding a section of the crop land combined with controlled drainage was found to be an efficient way of irrigating maize crop. The yields obtained with this system were comparable with those obtained with conventional subsurface irrigation. Flood irrigation combined with controlled drainage would be particularly commendable on relatively flat fields which have subsurface drains.

The aim of this work was to establish a range of suitable process parameters which can be utilized to produce needlepunched nonwoven fabrics for geotextile applications. Nonwoven fabrics were produced from 100% PP, a blend of 50/50% PP/kenaf and 100% kenaf fibres. The depths of needle penetration of 4, 7 and 10 mm, stroke frequencies of 250, 350 and 450 strokes/min and mass per unit area of 300, 600 and 900 g/m2 were utilized for producing the fabrics, on a Dilo loom. The effect of depth of needle penetration, stroke frequency and mass per unit area on the fabric properties, namely, tensile strength, puncture resistance, pore size, water permeability and transmissivity were analysed. In addition, the effect of chemicals, namely, 10% ammonium hydroxide (NH4OH), 10% sodium chloride (NaCl) and 3% sulphuric acid (H2SO4) solutions on degradation of the fabric was also studied. The results have shown that density, thickness and nominal weight of the needlepunched nonwoven fabrics were related to each other and they were influenced by stroke frequency, depth of needle penetration and feed rate of the needlepunching process. The increase in nominal weight of the fabrics also increases thickness and density of the fabrics. The tensile strength and puncture resistance of the fabrics increased with the increases in stroke frequency, depth of needle penetration and fabric mass per unit area. However, lower tensile strength and puncture resistance were achieved in the fabrics produced at lower stroke frequency, lower depth of needle penetration and lower mass per unit area. Bigger pores were resulted in the fabrics produced at lower stroke frequency, lower depth of needle penetration and lower mass per unit area, however, pore size decreased with increases in stroke frequency, depth of needle penetration and mass per unit area. Water permeability depends on the pore size, properties of the fibres, stroke frequency, depth of needle penetration and mass per unit area. Higher tensile strength and higher puncture resistance were achieved in the needlepunched nonwoven fabrics produced from 100% PP fibres, therefore, they are suitable for some load-bearing geotextile applications, such as reinforcement and separation. However, higher water permeability was achieved in the fabrics produced from 100% kenaf fibres, therefore, they are ideal for geotextile applications where good water permeability is required. Higher values for transmissivity were obtained in the fabrics produced from a blend of 50/50% PP/kenaf fibres, therefore they are suitable for drainage applications. The fabrics produced from a blend of 50/50% PP/kenaf fibres achieved better values of tensile strength, puncture resistance, pore size and water permeability in comparison to that produced from 100% PP and 100% kenaf fibres. However, better tensile strength and puncture resistance were achieved in the fabrics produced from 100% PP fibres and bigger pore size and higher water permeability were achieved in the fabrics produced from 100% kenaf fibres. Therefore, it can be suggested that the nonwoven fabrics produced from a blend of 50/50% PP/kenaf fibres can fulfil almost all requirements of geotextile applications, such as, filtration, separation, reinforcement and drainage. The fabrics produced from 100% PP fibres were not damaged or deteriorated when treated with all the three chemicals due to chemical inertness of polypropylene. However, the fabrics produced from a blend of 50/50% PP/kenaf and 100% kenaf fibres were damaged and deteriorated when treated with H2SO4.

Este trabalho apresenta resultados de ensaios de fluência confinada e não-confinada de geotêxteis não-tecidos agulhados. Algumas dificuldades encontradas durante o desenvolvimento dos equipamentos utilizados para realizar esses ensaios em laboratório são também apresentadas e discutidas. A etapa de investigação sem confinamento envolveu a utilização de geotêxteis de poliéster e de polipropileno. Os resultados confirmaram o grande potencial desses materiais em apresentar fluência assim como a maior susceptibilidade dos geotêxteis de polipropileno. No caso de ensaios com confinamento, tentativas de se tracionar um geotêxtil de polipropileno entre duas camadas de solo revelaram grandes dificuldades para manter a carga aplicada constante ao longo do corpo de prova, em virtude da existência de atrito nas interfaces solo-geotêxtil. Ensaios alternativos retirando-se o solo e envolvendo-se o geotêxtil em uma membrana de látex lubrificada apresentaram bons resultados, comprovando a redução da fluência em relação aos ensaios não confinados e denotando tratar-se de uma solução viável para investigar o real papel do confinamento na fluência dos geotêxteis. / This work presents results of confined and unconfined creep tests on nonwoven needle punched geotextiles. Withdraws found during the equipment development used to perform these tests are also highlighted and discussed. The unconfined tests encompassed the use of polyester and polypropylene geotextiles. Results confirm that these materials have a great potential to creep, being the polypropylene geotextiles the material with the greatest susceptibility. The confined tests where geotextile was placed between two soil layers revealed difficulties in keeping the applied load constant throughout the specimen due to soil-geotextile interface friction. Alternative tests performed without the soil and embedding the geotextile in a lubricated latex membrane showed good results, proving the decrease of creep in relation to unconfined tests. Thus, one can conclude that this is a viable solution towards the investigation of the real role that confinement plays in geotextile creep.

No description available.