Given the increasing consumption of plastic materials their reuse becomes a very topical issue. Recycling the single-cleaned plastic waste is simple, these products can be used as raw material or additive in the manufacture of new products. The problem remains the energy, economic and environmental demands in sorting, cleaning and eventual regranulation of waste to a suitable feedstock. This problem can be solved using technology that is able to handle multiple-type waste thermoplastics in further useful products.

Thesis (Ph.D.)--Tufts University, 2003. / Adviser: Daniel C. Jansen. Submitted to the Dept. of Civil Engineering. Includes bibliographical references (leaves 146-152). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

Concrete, as primary building material, is widely used in most construction project. For this reason, large amounts of concrete waste were generated from construction and demolition. One way to reuse concrete waste is to use it as backfill material for landfilling and road bases. While the demand for backfill material is decreasing as the basic infrastructure construction gradually completes. Another way to reuse concrete waste is to grind it and use it as aggregate in casting new concrete. However, the reuse as aggregate for casting concrete requires large amount of cement. It is unsustainable because the production of cement causes significant amounts of carbon dioxide emission. How to deal with the concrete waste in a sustainable way is presently an urgent issue. Powder compaction is a new approach to completely recycle concrete waste in an environmentally friendly way. This new method was studied in the Sakai lab of the Institute of Industrial Science, The University of Tokyo. The process consists of crushing and milling concrete waste into a fine powder, filling the powder into moulds and compacting it under high pressure. By this process concrete waste powder can be turned into a solid concrete with mechanical properties so that it has potentials to be used again as a building material. Data from previous studies show that the compacted concrete waste can reach strength for construction but the required compaction pressure is quite high. Wood flour can be added in compaction for improving tensile strength and reducing compaction pressure. Lignin is a wood substance that melts under high temperature, fills gaps and improves bonding between particles. Cellulose from the wood substance functions as fibres which improves tensile strength. Wood waste from production of timber building materials, furniture and other wooden products also forms a larger quantities. Recycling of concrete waste with wooden waste through heating compaction is a potentially sustainable method. This Master thesis presents research on the effect from different production conditions on the bending strength of recycled concrete waste with wood waste through heating compaction. The condition factors studied were compaction duration, compaction pressure, concrete proportion, mixture percentage, temperature and particle size of wood flour. To enhance the water resistance of this recycled product, different water resistance treatments were discussed theoretically. The independence of production condition factors was analysed using a statistic method. Results indicated that within a certain range, an increase in compaction duration, compaction pressure, the percentage of wood waste and temperature improves the bending strength of the recycled products. Using smaller particle size of wood flour cannot improve compaction but contribute to give higher bending strength. The mechanical properties of these recycled products suggest application as non-bearing building material, such as decoration tiles and bricks for partition walls. The application as a structural material is expected in the future as improvement treatments are discovered.

Submitted by Maicon Juliano Schmidt (maicons) on 2015-05-29T18:30:06Z No. of bitstreams: 1 Ângelo Cezar Fumagalli Rostirola.pdf: 4315210 bytes, checksum: ff48e5f928774ac2545c3ae6774d5dcf (MD5) / Made available in DSpace on 2015-05-29T18:30:06Z (GMT). No. of bitstreams: 1 Ângelo Cezar Fumagalli Rostirola.pdf: 4315210 bytes, checksum: ff48e5f928774ac2545c3ae6774d5dcf (MD5) Previous issue date: 2013-10-24 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / SINDUSCON-NH - Sindicato das Indústrias da Construção Civil Novo Hamburgo / A construção civil atualmente é a indústria com maior crescimento no Brasil, fomentada por financiamentos e programas do governo federal. É também uma das indústrias que mais consome recursos naturais e energia, além de ser a principal geradora de resíduos sólidos urbanos. Grande parcela destes recursos naturais consumidos pela construção é formada pelos agregados. Uma alternativa econômica e ambientalmente correta, para diminuir a extração deste material, é a sua substituição por algum outro material, se possível por um resíduo, como apontam várias pesquisas. A busca por materiais e produtos ecologicamente corretos está em uma crescente, assim como os estudos para a reciclagem de diversos resíduos. A união entre produtos que consomem um volume menor de matéria-prima com o emprego de resíduos na sua produção parece uma saída viável para um desenvolvimento mais sustentável. Artefatos para a construção civil produzidos com concreto celular autoclavado (CCA) utilizam até quatro vezes menos materiais quando comparados a produtos com características semelhantes, produzidos com concreto convencional, cerâmico, entre outros. Além do menor consumo dos materiais constituintes, o concreto celular possui outras propriedades interessantes, como: suficiente resistência à compressão; isolamento térmico e acústico; baixa densidade; resistência ao fogo. Esta pesquisa teve como objetivo principal avaliar a influência da substituição parcial do agregado natural por agregado reciclado de concreto (ARC) na produção de concreto celular autoclavado. Após realização de estudos-piloto, optou-se pelo emprego da proporção de Cimento e Agregado Natural (AN) de 67% e 33% e sobre estes 0,45% de Cal e 0,3% de Alumínio com relação água/sólidos igual a 0,32. Foram empregados Cimento Portland CP-V ARI, Cal calcítica, areia natural e agregado fino reciclado de concreto, em teores de 0%, 25% e 50%. A dimensão máxima do agregado empregado na produção de CCA é de 150 µm. A cura foi realizada em autoclave após um tempo de espera de 24 horas a partir do início da mistura, por um período de 6 horas. Foram avaliadas a resistência à compressão, a absorção de água capilar, a massa específica e a porosidade. Os ensaios de resistência à compressão foram realizados em 48 e 72 horas, e a absorção de água, em corpos de prova preparados e acompanhados pelo período de 96 horas. A microestrutura dos CCA produzidos foi caracterizada por microscopia eletrônica de varredura (MEV). Verificou-se que existem expressivas alterações nas propriedades do CCA produzidos com ARC em substituição do AN, com a tendência de aumentar a densidade de massa aparente, bem com a resistência à compressão, a medida que aumenta-se o teor de ARC. Na análise dos resultados, percebeu-se que o uso de ARC alterou as propriedades dos concretos produzidos neste estudo exploratório, sem, entretanto, inviabilizar o seu emprego. Com um ajuste da dosagem, pode ser obtido um CCA produzido com ARC, cujo comportamento seja compatível com o comportamento de CCA produzido somente com o AN. / In the last years, the Brazilian construction industry is among those of national production sectors that have been having a great growing, mostly due to the incentive from the government and due to financed resources by private and public agents. This industry is also one of the major consumers of natural resources and energy, besides being the main generator of solid waste. One of these natural resources used in the constructions is sand. An environmentally friendly and economical alternative to reduce the extraction of natural resources is the use of recycled waste. The associated use of low volume of raw materials with alternative materials, like waste, is one of the ways to get more sustainability in the construction sector. Construction and building components made with autoclaved cellular concrete (ACC) employ four times less material than others with the same function. Other advantage of ACC is the performance of its properties like compressive strength, thermal and acoustic behavior, lower density, fire resistance. The aim of this research was to investigate the use of fine grains from recycled concrete aggregate (ARC) as partial sand replacement in the production of autoclaved aerated concrete. With the goal to find the mix proportion some pilot studies were made. After this, it was chosen a relation of 67% of cement and 33% of natural fine aggregate (sand). The lime was used in the amount of 0.45% of total cement and sand, and 0.3% of aluminium. The water to total solids ratio was 0.32. It was employed Portland cement type V according to Brazilian standards, calcitic lime, natural sand and ARC passing in sieve with 150 micron opening. The replacement rate of sand by ARC was 0%, 25% and 50%. From 24 hours after the mixing of materials, the samples were submitted to steam curing in an autoclave chamber for 6 hours. It was evaluated the compressive strength, the density, the capillary water absorption and porosity. The compression strength tests were performed at 48 and 72 hours. Water absorption tests were conducted for 96 hours after samples preparing. The capillary porosity was calculated with the capillary water absorption data. ACC's microstructure analysis was done by scanning electron microscopy (SEM). The results showed in general that the behavior of ACC produced with ARC differs significantly from the ACC produced with natural aggregate. When the ARC rate increases the apparent specific gravity also increases as well as the compressive strength. The observed increase in the apparent specific gravity is not desired. However this behavior of ACC done with RCA does not prevent the use of this recycled aggregate. An optimized study of pre-wetting of RCA could improve its performance as aggregate for use in ACC, once its grain size showed to be appropriated for this kind of use.

Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Yapı Eğitimi Anabilim Dalı, 2008. / Kaynakça var.

L‟élimination de certains déchets est un enjeu important en Côte d‟Ivoire. Une des solutions proposée est d‟envisager l‟utilisation de ces déchets comme granulats dans les bétons. Les travaux présentés dans ce document portent sur l‟incorporation de quatre différents déchets.La première étude porte sur un béton confectionné avec trois types de déchets : du verre concassé, du ciment durci concassé et des pneus découpés. Elle a été réalisée en deux phases. Dans la première ces déchets ont été incorporés à du béton pour remplacer 100% des graviers (substitution totale). Dans la seconde une substitution (massique) partielle de gravier a été réalisée dans les proportions suivantes 5, 10, 15, 20, 25 et 30 %, la matrice mortier et le rapport eau-ciment restant identiques. Après une maturation de 28 jours leurs résistances en compression ont été déterminées. Ces résultats montrent que les bétons de recyclât ont une résistance inférieure à celui des bétons de concassé de gravier. Toutefois, la résistance mécanique baisse avec l‟augmentation de la substitution. Une loi donnant la résistance en fonction du taux de recyclât a été établie. De plus, la spécificité des granulats de caoutchouc (résistance à la fissuration) est remarquée.Par ailleurs, les résistances des bétons de recyclât ont permis d‟établir une loi donnant la résistance en fonction des caractéristiques des agrégats et de leur fraction volumique. Une modélisation analytique a été proposée pour prédire la résistance des bétons en fonction de la taille et du volume des granulats recyclés.Les granulats issus du concassage des bétons frais (retour de toupie) utilisés comme substituant des granulats naturels a été menée pour évaluer leur potentiel. Un plan d‟expériences statistique à deux variables (% de recyclât dans le sable et % de recyclât dans le gravier) a été utilisé pour réduire le nombre de mesures. Les proportions de remplacement utilisées sont : 0%, 50% et 100%. Les propriétés mécaniques ont été déterminées par différentes méthodes destructives (résistance à la compression et à la traction) et non destructives (ondes ultrasonores pour évaluer l‟élasticité du matériau). De même, les propriétés physiques telles que la porosité accessible à l‟eau, la masse volumique ont été mesurées. Ces résultats montrent une bonne corrélation entre le pourcentage de remplacement et les propriétés physiques et mécaniques de ce béton / Waste management is an important issue for Côte d‟Ivoire. Among many possibilities, recycling wastes as aggregates for concrete is a solution that deserves to be evaluated. In this study four recycled aggregates are tested: crushed glass, tire cut rubber, hardened cement and fresh concrete waste. There properties are compared to those of natural aggregates.A first study is realized in Côte d‟Ivoire on glass, rubber and hardened cement. Concrete is realized and tested in compression (cylindrical 16x32 specimens). A mix with an increasing quantity of coarse aggregates is tested for each recycled material (20 %, 25 %, 30 % and 50 % in mass of fine and coarse aggregates). It is shown that the strength decreases with the replacement rate and that the decrease depends on the replacing material. The materials ranged in the following increasing order: rubber, glass, hardened cement and natural aggregates. A power law is established which gives the compressive strength as function of the mix and the materials characteristics. Analytical modeling was proposed for predincting the strength with respect to recycled aggregates size and volume.Another experiment is also made on glass and rubber, where partial replacement in increasing percentage is tested. Natural aggregates are partially replaced in the mix with the ranges of 5, 10, 20, 25 and 30 % by rubber and glass. The compressive strength is determined and a decrease is observed for the two materials. In the case of rubber a high decrease in observe with the replacement. In the case of glass a decrease occurs between 0 and 5 % replacement then the strength remains constant with the replacement rate. The third experiment is made with partial replacement of fresh recycled concrete (excess of ready-mixed concrete from concrete mixing plant which is hardened and then crushed). A plan of experiments is made which allows a polynomial law to be drawn giving the strength as a function of the recycled proportion. Other properties (Young modulus, P wave velocity, porosity, density, etc) have been determined and their relation with replacement rate computed.

CNPq / Este trabalho teve como objetivo desenvolver novos compósitos para construção civil e pesquisar mudanças nas propriedades mecânicas e nas estruturas morfológicas durante os períodos de cura de: 3, 7, 14, 28, 60 e 90, 180 dias e 1 ano. Foram desenvolvidas 23 composições utilizando como matérias primas resíduos de concreto, lodo da anodização de alumínio e resíduos da produção da cal. Para cada composição foram moldados 60 corpos de prova de 20mm x 20mm e compactadas as misturas com pressão de 10 MPa, com tempo de permanência desta pressão de 30 s. Os resultados dos ensaios de resistência à compressão uniaxial, absorção de água e dilatação prevaleceram às demandas das Normas Brasileiras. Dentre todas as composições destaca-se a de número 17, visto que não incorpora um valor muito alto de resíduo da produção de cal e sua resistência aumenta com o passar do tempo. Esta composição obteve resistência à compressão de 6,76MPa aos 28 dias de cura e 12,48MPa aos 180 dias de cura, também foram realizadas análises de processos físico-químicos de formação de estruturas, para explicação deste ganho de resistência. / The aim of presented research was to develop new composites for construction and analyze changes of mechanical properties and morphological structures during the healing periods: 3, 7, 14, 28, 60 and 90 and 180 days and 1 years. There were developed 23 compositions using concrete waste, sludge from anodizing aluminum process and waste of lime production as raw materials. For each composition 60 samples of 20mm x 20mm cylinder size were extracted with pressure of 10 MPa, which was kept for 30 seconds for each specimen. The results of the uniaxial compression resistance, water absorption and expansion tests exceeded Brazilian Standards. Among all compositions the number 17 is highlighted, since it does not contain high amount of lime production waste and its resistance increases over time. This composition reached compressive strength resistance of 6,76MPa after 28 days of healing and 12,48MPa over 180 days, analysis of physical-chemical processes was also carried out in order to explain high strength gain.

CNPq / Este trabalho teve como objetivo desenvolver novos compósitos para construção civil e pesquisar mudanças nas propriedades mecânicas e nas estruturas morfológicas durante os períodos de cura de: 3, 7, 14, 28, 60 e 90, 180 dias e 1 ano. Foram desenvolvidas 23 composições utilizando como matérias primas resíduos de concreto, lodo da anodização de alumínio e resíduos da produção da cal. Para cada composição foram moldados 60 corpos de prova de 20mm x 20mm e compactadas as misturas com pressão de 10 MPa, com tempo de permanência desta pressão de 30 s. Os resultados dos ensaios de resistência à compressão uniaxial, absorção de água e dilatação prevaleceram às demandas das Normas Brasileiras. Dentre todas as composições destaca-se a de número 17, visto que não incorpora um valor muito alto de resíduo da produção de cal e sua resistência aumenta com o passar do tempo. Esta composição obteve resistência à compressão de 6,76MPa aos 28 dias de cura e 12,48MPa aos 180 dias de cura, também foram realizadas análises de processos físico-químicos de formação de estruturas, para explicação deste ganho de resistência. / The aim of presented research was to develop new composites for construction and analyze changes of mechanical properties and morphological structures during the healing periods: 3, 7, 14, 28, 60 and 90 and 180 days and 1 years. There were developed 23 compositions using concrete waste, sludge from anodizing aluminum process and waste of lime production as raw materials. For each composition 60 samples of 20mm x 20mm cylinder size were extracted with pressure of 10 MPa, which was kept for 30 seconds for each specimen. The results of the uniaxial compression resistance, water absorption and expansion tests exceeded Brazilian Standards. Among all compositions the number 17 is highlighted, since it does not contain high amount of lime production waste and its resistance increases over time. This composition reached compressive strength resistance of 6,76MPa after 28 days of healing and 12,48MPa over 180 days, analysis of physical-chemical processes was also carried out in order to explain high strength gain.