• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • Tagged with
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Avalia??o de blocos intertravados com agregados reciclados provenientes de res?duos de constru??o e demoli??o de obras do munic?pio de Natal/RN / Evaluation of interconnected blocks with recycled construction and demolition of Natal/RN

Pederneiras, Cinthia Maia 25 February 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-04-03T23:07:53Z No. of bitstreams: 1 CinthiaMaiaPederneiras_DISSERT.pdf: 5172350 bytes, checksum: 869c10f054af1edda7a401ef7faf0e62 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-04-11T22:49:22Z (GMT) No. of bitstreams: 1 CinthiaMaiaPederneiras_DISSERT.pdf: 5172350 bytes, checksum: 869c10f054af1edda7a401ef7faf0e62 (MD5) / Made available in DSpace on 2017-04-11T22:49:22Z (GMT). No. of bitstreams: 1 CinthiaMaiaPederneiras_DISSERT.pdf: 5172350 bytes, checksum: 869c10f054af1edda7a401ef7faf0e62 (MD5) Previous issue date: 2017-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Este trabalho tem como objetivo analisar a utiliza??o dos res?duos de constru??o e demoli??o de obras gerados no munic?pio de Natal/ RN como agregados reciclados para a fabrica??o de blocos de pavimenta??o intertravada. Na primeira etapa foi realizada a caracteriza??o minuciosa dos agregados mi?dos e gra?dos. Os ensaios utilizados para este fim foram granulometria, massa unit?ria, massa especifica, ?ndice de forma, material pulverulento, material org?nico, absor??o de ?gua, inchamento, fluoresc?ncia de raio X (FRX), difratograma de raio X (DRX) e microscopia eletr?nica de varredura (MEV). A partir dos ensaios de caracteriza??o de agregados naturais e reciclados pode-se estabelecer uma compara??o das propriedades f?sicas, qu?micas e microsc?picas. A fabrica??o dos blocos foi realizada com o tra?o em volume e substitui??o de 100% de agregados reciclados. As vari?veis analisadas foram as condi??es dos agregados reciclados na mistura, investigando seu desempenho na condi??o seca, lavada e saturada. Os ensaios para analisar a viabilidade t?cnica dos blocos, conforme a norma espec?fica NBR 9781 (2013), foram resist?ncia ? compress?o (em idades de 7, 14, 28 e 270 dias) e absor??o de ?gua (aos 28 e 270 dias). Para avaliar o desgaste dos blocos foi constru?do um prot?tipo, o qual foi analisado ap?s um ano de constru??o. Os blocos fabricados apenas com agregado mi?do reciclado apresentaram um incremento na resist?ncia ? compress?o quando comparados aos blocos de refer?ncia. J? os blocos confeccionados com agregado gra?do reciclado obtiveram as menores resist?ncias. Observou-se tamb?m que quando os agregados reciclados s?o lavados apresentam melhor desempenho no produto final. Os resultados obtidos mostraram-se satisfat?rios para a aplica??o dos blocos em ruas de baixo movimento e pouca carga. Com o intenso crescimento dos res?duos oriundos da constru??o civil, destaca-se a relev?ncia desta pesquisa, a qual prop?e a fabrica??o de um produto sustent?vel que visa minimizar o uso dos recursos naturais e promover uma destina??o adequada para os res?duos gerados. / This work aims to analyze the use of construction and demolition waste in Natal / RN as recycled aggregates for precast concrete paving blocks. In the first stage, the detailed characterization of the aggregates (fine and coarse) was carried out. The tests used for this purpose were grading curves, bulk density, dry specific density, powdery material, organic material, water absorption, X-ray fluorescence (FRX), X-ray diffraction (XRD) and electron microscopy of Scanning (SEM). From the characterization tests of natural and recycled aggregates is possible to analyze physical, chemical and microscopic properties. Ten different mixes were analyzed with an effective water/cement ratio of 0.4 for recycled rates of coarse and fine aggregates of 100%. This research analyzed the conditions of the recycled aggregates in the mixture (dry, washed and saturated), evaluation of the performance of aggregates in a concrete mix. The tests to analyze the technical viability of the concrete blocks, according to the specific norm NBR 9781 (2013), were compressive strength (at ages of 7, 14, 28 and 270 days) and water absorption (at ages of 28 and 270 days). To evaluate the durability, a prototype was constructed, which was analyzed after one year of construction. The blocks made with only recycled sand showed an increase in the results of compressive strength when compared to the reference blocks. The blocks made with recycled coarse obtained the smallest resistance. It was also observed that when the recycled aggregates are washed present a better performance in the final product. The results obtained were satisfactory for the application of the blocks in streets of low movement and low load. With the intense growth of waste from civil construction, the relevance of this research is proposes the manufacture of a sustainable product that aims to minimize the use of natural resources and promote a proper destination for the waste generated.
2

Efeitos da incorpora??o de areia reciclada de res?duos de constru??o e demoli??o (RCD) em argamassas mistas de revestimento / Effects of the incorporation of recycled sand of construction and demolition waste (CDW) in mixed coating mortars

Ferreira, Ruan Landolfo da Silva 31 March 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-06-02T22:25:25Z No. of bitstreams: 1 RuanLandolfoDaSilvaFerreira_DISSERT.pdf: 5373766 bytes, checksum: 13b9b589b54063a3ed114c1d60d827c5 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-06-08T22:20:54Z (GMT) No. of bitstreams: 1 RuanLandolfoDaSilvaFerreira_DISSERT.pdf: 5373766 bytes, checksum: 13b9b589b54063a3ed114c1d60d827c5 (MD5) / Made available in DSpace on 2017-06-08T22:20:54Z (GMT). No. of bitstreams: 1 RuanLandolfoDaSilvaFerreira_DISSERT.pdf: 5373766 bytes, checksum: 13b9b589b54063a3ed114c1d60d827c5 (MD5) Previous issue date: 2017-03-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O processo de constru??o, reforma e demoli??o, pode ocasionar significativos problemas ao meio ambiente, devido a extra??o de mat?rias primas e a destina??o inadequada dos res?duos gerados. Em especial os res?duos de constru??o e demoli??o (RCD) que, comumente correspondem a mais da metade dos res?duos s?lidos urbanos, tem como principais destinos, terrenos baldios, margens de estradas e rios, acarretando s?rios impactos ambientais, sociais e econ?micos. Atualmente, a reutiliza??o de agregados reciclados (AR), especialmente de composi??o mista, ? estudada em menor grau, quando comparado aos AR de concreto. Com isso, por n?o possuir alternativas para sua utiliza??o, uma grande quantidade desse tipo de AR ? armazenada pelas usinas. Nesse sentido, buscou-se analisar a viabilidade t?cnica e econ?mica da utiliza??o de AR com diferentes composi??es granulom?tricas e em condi??o lavada, ? n?veis de substitui??o de 25, 50, 75 e 100% do agregado natural (AN), na produ??o de argamassas mistas de revestimento. Para a produ??o das argamassas, utilizou-se cimento CP II Z-32, cal CH-I e uma propor??o em volume de 1:1:6, cujo teor de ?gua foi determinado para as misturas alcan?arem uma consist?ncia de 260 mm. Inicialmente, analisou-se as propriedades f?sicas, qu?micas, mineral?gicas e microestruturais dos agregados e da fra??o de finos (<0,15 mm). Buscando avaliar a viabilidade t?cnica das argamassas foram caracterizadas no estado fresco, por meio dos ensaios de consist?ncia, reten??o de ?gua, densidade de massa e teor de ar incorporado. E no estado endurecido, a resist?ncia ? compress?o, resist?ncia ? tra??o na flex?o, m?dulo de elasticidade din?mico, absor??o por capilaridade, absor??o por imers?o, resist?ncia de ader?ncia e fissura??o. Foi utilizado o custo para produzir 1 m? de argamassa visando avaliar a viabilidade econ?mica. Constatou-se, que as argamassas com AR, independentemente de sua composi??o granulom?trica ou condi??o, apresentaram maior consumo de ?gua, menor densidade de massa e teor de ar incorporado, assim como adequada capacidade de reten??o de ?gua. No estado endurecido, as argamassas que possu?am AR com a presen?a de finos, apresentaram maior resist?ncia, maior m?dulo de elasticidade e menor porosidade e permeabilidade. No entanto, o desempenho dos revestimentos frente ao potencial de ader?ncia ao substrato e a quantidade de fissuras, foi inferior, confirmando a premissa de que a utiliza??o de AR com finos n?o ? indicada para a produ??o de argamassas de revestimento. Quanto a viabilidade econ?mica, ao incorporar o AR, o custo para produzir 1 m? de argamassa diminui. No entanto, admite-se que ? vi?vel a utiliza??o de AR para a produ??o de argamassas de revestimento, especialmente quando se disp?e de agregados com adequada composi??o granulom?trica, isentos de finos e em condi??o lavada. / The construction, reform and demolition process can cause significant problems to the environment due to the extraction of raw materials and an inadequate disposal of the waste generated. In particular, construction and demolition wastes (CDW), which commonly correspond to more than half of urban solid waste, have as main destinations, vacant lots, roadsides and rivers, causing serious environmental, social and economic impacts. Currently, a recycling of recycled aggregates (RA), especially of mixed composition has been studied to lesser extent when compared to RA of concrete. Therefore, because it does not have alternatives for their use, a large amount of this type of RA is stored by plants. In this sense, the aim of this research is to analyze the technical and economic viability of the use of RA with different grain size and washed condition compositions, at 25, 50, 75 and 100% substitution levels of the natural aggregate (NA), in the production of mixed mortars. For the production of mortars, CP II Z-32 cement, lime CH-I and a volume ratio of 1:1: 6 were used. Water content was adjusted to mixtures with a consistency of 260 mm. Initially, the physical, chemical, mineralogy and microstructural properties of the aggregates and the fines fraction (<0.15 mm) were analyzed. Seeking to assess the technical feasibility of mortars were characterized fresh, through consistency tests, water retention, bulk density and entrained air content. And in the hardened state, the compressive strength, flexural tensile strength, dynamic modulus of elasticity, water absorption by capillarity, immersion absorption, adherence strength and susceptibility to cracking. The cost of production of 1 m? of mortar was used for an assessment of economic feasibility. It was showed that, as mortars with RA, regardless of their size distribution or condition, presented higher water consumption, lower bulk density and incorporated air content, as well as water retention capacity. In the hardened state the mortars had RA with the presence of thin, had higher resistance, higher modulus and lower porosity and permeability. However, the performance of the mortar coverings to the potential of adhesion to the substrate and a number of cracks has been lower, confirming a premise that the use of RA with fines is not indicated for coating mortars. As for the economic feasibility, to incorporate RA, the cost to produce 1 m? of mortar decreases. However, it is recognized that the use of RA for the production of coating mortars is feasible, especially when aggregates with adequate size distribution are available, without fines and in washed condition.

Page generated in 0.0935 seconds