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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.
11

Propiedades físico mecánicas del concreto reciclado para Lima Metropolitana

Velásquez Pacco, Lucio Martin January 2015 (has links)
En la actualidad en gran parte del mundo se viene proponiendo e impulsando las políticas ambientales que puedan reducir el problema de la degradación de los recursos naturales a la que está siendo sometido el planeta. A tal efecto se plantea la realización de esta investigación para tratar de determinar el grado de influencia en las propiedades físicas del concreto fabricado con agregados reciclados procedentes de la trituración. La variable seleccionada para la investigación ha sido: el porcentaje de sustitución del agregado grueso natural por agregado grueso reciclado en la dosificación del concreto. El objetivo general de la investigación es analizar en qué medida la cantidad de agregado grueso reciclado usado en la dosificación de la mezcla influye en las propiedades mecánicas del concreto. El tipo de investigación fue básica y cualitativa, la metodología. Se usó una metodología experimental y transversal. El análisis de los resultados experimentales indican que la resistencia a la compresión y a la tracción no se ven afectadas notoriamente al reemplazar el 20% de agregado natural, en un mayor porcentaje de reemplazo , la resistencia empieza a decaer directamente proporcional a un mayor porcentaje de agregado reciclado. Today in much of the world has been proposing and promoting environmental policies that can reduce the problem of the degradation of natural resources that the planet is undergoing. For this purpose the realization of this research to try to determine the degree of influence on the physical properties of concrete made with recycled aggregate from crushing arises. The selected research variable was the percentage of coarse natural aggregate replacement by recycled coarse aggregate concrete proportions. The overall objective of the research is to analyze to what extent the amount of recycled coarse aggregate used in the dosage of the mixture influences the mechanical properties of concrete. The research was basic and qualitative methodology. An experimental and transversal approach was used. Analysis of the experimental results indicate that the compressive strength and tensile strength are not affected noticeably by replacing 20% of natural aggregate, a higher percentage replacement, resistance begins to drop directly proportional to a higher percentage of added recycling.
12

Mejoramiento en la resistencia a la compresión, flexión y tracción del concreto con agregado grueso reciclado, agregado fino natural y vidrio triturado para viviendas unifamiliares en lima metropolitana

Carrasco Villanueva, Sara Isabelle, Ccorahua Espinoza, Fiorela Ytala 15 October 2021 (has links)
En los últimos años existe una demanda cada vez más creciente de infraestructura; actualmente en el Perú el sector construcción ha ido en constante crecimiento; sin embargo, es uno de los más contaminantes debido a la fabricación del concreto y sus componentes, ya que la industria concretera es responsable de la extracción de recursos no renovables; siendo el concreto el material fundamental para los diferentes tipos de proyectos en vías de desarrollo. Frente a este entorno, se propone como alternativa sostenible el uso de residuos de demolición, es decir agregado grueso de concreto reciclado en reemplazo del agregado grueso natural; sin embargo, en investigaciones anteriores el reemplazo de este, presenta una disminución en la resistencia a la compresión y flexión de 10% - 25% y 23.7% respectivamente. Por esta razón, se seleccionó el vidrio triturado proveniente del reciclado de botellas incoloras, este es un material eco amigable y de características que contribuyen en la resistencia del concreto. En consecuencia, se propone el uso de estos agregados reciclados en reemplazo total y parcial del agregado grueso y fino respectivamente. Los resultados de estos ensayos indicaron un aumento en las propiedades mecanicas del concreto y el porcentaje óptimo de reemplazo de vidrio triturado es 20%, en donde se obtuvo un incremento de 12.33% en la Resistencia a la compresión, 17.19% en la Resistencia a la flexion y 1.98% en la Resistencia a la tracción. / In recent years there is an increasingly growing demand for infrastructure; Currently in Peru the construction sector has been in constant growth; However, it is one of the most polluting due to the manufacture of concrete and its components, since the concrete industry is responsible for the extraction of non-renewable resources; concrete being the fundamental material for the different types of projects under development. Faced with this environment, the use of demolition waste is proposed as a sustainable alternative, that is, coarse aggregate of recycled concrete to replace the natural coarse aggregate; However, in previous research, its replacement shows a decrease in compressive and flexural strength of 10% -25% and 23.7%, respectively. For this reason, the crushed glass from the recycling of colorless bottles was selected since it is an eco-friendly material and features that contribute to the strength of the concrete. Consequently, the use of these recycled aggregates is proposed in total and partial replacement of the coarse and fine aggregate respectively. The results of these tests indicated an increase in the mechanical properties of the concrete and the optimum percentage of replacement of crushed glass is 20%, where an increase of 12.33% in Compressive Strength, 17.19% in Resistance to Compression was obtained. flexion and 1.98% in tensile strength. / Tesis
13

Mejoramiento de las propiedades mecánicas del concreto con ACR empleando aditivo nanosílice / Improvement of the mechanical properties of concrete with ARC and nanosilize additive

Ayala Aguilar, Kevin Josué, Ccallo Pérez, Marie 06 October 2020 (has links)
En este artículo se analiza la influencia de un aditivo a base de nanosilice en el concreto elaborado con agregado a partir de concreto reciclado. Para lo cual, se ha realizado un programa de laboratorio donde se analizan las propiedades físicas de los materiales y las propiedades en estado fresco y endurecido del concreto a distintas edades. El objetivo principal del estudio es demostrar las mejoras cuantitativas de resistencia a compresión y tracción del concreto con ACR empleando nanosilice. Asimismo, el diseño óptimo para los casos propuestos es la mezcla M4 (100% ACR y 1% nanosilice) con el cual se logra mejorar en 21% respecto a la muestra M3 (100% ACR) a 28 días. Finalmente, el diseño M4 tiene una mayor resistencia a compresión comparado con la mezcla M0 (1) concreto convencional sin nanosilice. Por consiguiente, la utilización del concreto con ACR es factible en términos de resistencia. / This article discusses the influence of a nanosilize based admixture on concrete made with aggregate from recycled concrete. For which, a laboratory program has been carried out where the physical properties of the materials and the properties in the fresh and hardened state of concrete at different ages are analyzed. The main objective of the study is to demonstrate the quantitative improvements of resistance to compression and tension of concrete with ACR using nanosilice. Likewise, the optimal design for the proposed cases is the M4 mixture (100% ACR and 1% nanosilize) with which it is possible to improve by 21% compared to the M3 sample (100% ACR) at 28 days. Finally, the M4 design has a higher compressive strength compared to the conventional concrete mix M0 (1) without nanosilize. Therefore, the use of concrete with ACR is feasible in terms of strength. / Tesis
14

Diseño de concreto reciclado para construcción de muros prefabricados de viviendas modulares con el Método ACI en Villa María del Triunfo / Recycled concrete design for construction of prefabricated walls of modular homes with the ACI Method in Villa María del Triunfo

Guerra Aguilar, Wilfredo Virgilio, Niño Guevara, Alan Ricardo 18 February 2022 (has links)
El objetivo de la presente investigación es diseñar concreto con agregado grueso reciclado con resistencia a la compresión de f´c = 210 kg/cm2 y demostrar su viabilidad para construcción de muros prefabricados de viviendas modulares con el método ACI en el distrito de Villa María del Triunfo, Lima. Basándose en ello, se busca incentivar el reciclaje para la fabricación de viviendas modulares que ofrezcan una mejor calidad de vida. Se desarrolló una investigación de tipo aplicada y experimental, realizado con una muestra de 280 probetas y 10 vigas de concreto natural y reciclado. Como técnica principal se utilizó el estudio de campo y como instrumento, el análisis de datos cuantitativos. Se recolectó un conglomerado de 5 m3 de material de demolición de una acera de concreto y se realizó el proceso de transformación para obtener agregado grueso reciclado en tamaño nominal de 1”. Se diseñó mezclas de concreto con agregado natural y agregado reciclado al 25%, 50%, 75% y 100% de sustitución, realizándose ensayos por resistencia a la compresión, flexión y tracción al concreto endurecido. Asimismo, se realizó un análisis de costos sobre la producción por m3 entre el concreto con agregado reciclado versus el concreto con agregado convencional. Además, se diseñó un módulo familiar con concreto reciclado y se analizó su comportamiento estructural en un software. Finalmente, el agregado grueso de concreto reciclado puede sustituir al 100% la piedra natural triturada y con ello disminuir la explotación de la corteza terrestre para la extracción de piedra natural. / The research objective is to design concrete with recycled coarse aggregate with compression resistance of f´c = 210 kg/cm2, and to demonstrate its viability for the construction of prefabricated walls of modular homes with the ACI method in the district of Villa María del Triunfo in Lima. According to this, it seeks to encourage the use of recycled materials in modular homes manufacturing which also offers a better quality of life. Applied experimental research was carried out with a sample of 280 specimens and 10 beams of natural and recycled concrete. The main technique used was the field study, and the instrument, quantitative data analysis. A conglomerate of 5 m3 of demolition material was collected from a concrete sidewalk and the transformation process was carried out to obtain recycled coarse aggregate in nominal size of 1". Mixtures of concrete with natural aggregate and recycled aggregate at 25%, 50%, 75% and 100% replacement levels were designed, performing tests for resistance to compression, bending and traction to hardened concrete. In addition, a cost analysis on the production per m3 was carried out, comparing concrete with recycled aggregate versus concrete with conventional aggregate. Furthermore, a module with recycled concrete was designed and its structural behavior was analyzed in a structural design software. In conclusion, the coarse recycled concrete aggregate can replace 100% crushed natural stone and can thereby reduce the earth's crust exploitation for the extraction of natural stone. / Tesis
15

[en] ASSESSMENT ON MIX DESIGN AND FLEXURAL PERFORMANCE OF REINFORCED CONCRETE SHORT BEAMS MADE WITH MIXED RECYCLED COARSE AGGREGATE / [pt] AVALIAÇÃO DA DOSAGEM E DESEMPENHO À FLEXÃO DE VIGAS CURTAS DE CONCRETO ARMADO PRODUZIDAS COM AGREGADO GRAÚDO RECICLADO MISTO

FERNANDA DE ANDRADE SALGADO 03 July 2023 (has links)
[pt] Nas últimas décadas, o setor da construção tem procurado mitigar os efeitos da sua atividade desenvolvendo novas formulações de materiais mais sustentáveis. Diversos estudos têm analisado a viabilidade do uso de agregado reciclado a partir de resíduos de construção e demolição, em substituição ao agregado natural. As normas internacionais restringem o uso de agregados reciclados em concreto estrutural, geralmente limitando-se a agregados reciclados compostos apenas por fragmentos cimentícios. Entretanto, a utilização de agregado reciclado com certo teor de fragmentos cerâmicos simplificaria o processo de separação antes da reciclagem, tornando-a mais viável e barata. Neste trabalho, observou-se que mesmo a substituição de 100 por cento do agregado natural por agregado reciclado misto não causou impacto significativo nas propriedades do concreto fresco e endurecido. Os resultados experimentais também mostraram que o Modelo do Empacotamento Compressível pode ser aplicado com sucesso para a dosagem de concretos produzidos com agregado reciclado misto até a classe de resistência C50. Por fim, os resultados à flexão de vigas curtas de concreto armado mostraram que as prescrições da norma brasileira ABNT NBR 6118:2014 para concretos convencionais também podem ser aplicadas a vigas de concreto com agregado reciclado misto com até 15 por cento de fragmentos cerâmicos. / [en] In the last decades, the construction sector has tried to mitigate the adverse effects of its activity by developing new formulations for more sustainable materials. Several studies have analyzed the feasibility of using recycled aggregate from construction and demolition waste in concrete to replace natural aggregate. International standards restrict the use of recycled aggregates in structural concrete, usually limiting to recycled aggregates composed only of cement-based fragments. However, using recycled aggregate with a certain content of ceramic fragments would simplify the separation process before recycling, making it more feasible and cheaper. In this work, it was observed that even replacing 100 percent of the natural aggregate with mixed recycled aggregate did not cause a significant impact on fresh and hardened concrete properties. The experimental results also showed that the Compressible Packing Model could be successfully applied for the mix design of mixed recycled aggregate concrete up to strength class C50. Finally, the results regarding the flexural behavior of short reinforced concrete beams showed that the prescriptions of the Brazilian standard ABNT NBR 6118:2014 for the bending behavior of conventional concrete beams could also be applied to beams made with concrete with mixed recycled aggregate up to 15 percent of ceramic fragments.

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