A reciclagem de resíduos de construção e demolição (RCD) é uma prática utilizada desde a Antigüidade, quando cidades destruídas pela guerra e por catástrofes naturais eram reerguidas dos próprios escombros. Hoje, ela é utilizada em larga escala em vários países da Europa e nos EUA. No Brasil, onde a preocupação com o destino desses resíduos é bem mais recente, poucos municípios se preocupam com o gerenciamento dos RCD. Os efeitos disso são visíveis: os resíduos ainda são depositados irregularmente em terrenos baldios, vias públicas, várzeas, córregos e até mesmo em áreas de proteção ambiental, causando a proliferação de vetores nocivos à saúde, enchentes e diversos prejuízos ao meio-ambiente. Assim, este trabalho tem como objetivo propor soluções que busquem a minimização desse impacto ambiental por meio da utilização dos RCD como agregados na fabricação de blocos de concreto. Os testes em laboratório e a comparação dos resultados obtidos com os das práticas convencionais provam a viabilidade da utilização dos resíduos, tanto em termos ambientais quanto econômicos, além de garantir que o emprego dos RCD atenda a todas as normas vigentes. Com isso, reafirmou-se o compromisso com a preservação ambiental, pois a reciclagem desse tipo de entulho, além de ajudar a removê-lo da paisagem urbana, ainda gera diferenciais consideráveis em termos de economia de energia e de recursos naturais não-renováveis que seriam utilizados como matérias-primas, reduzindo a poluição do ar, da água, do solo, desafogando aterros sanitários, e visando atingir o desenvolvimento sustentável. / Recycling of construction and demolition refuses (CDR) is a has been practiced since ancient history, when cities that were destroyed by war and natural disasters were rebuilt from their own ruins. Today, it is used in large scale in many countries in Europe and in the USA. In Brazil, where the concern with the destination of this kind of refuses is much more recent, few cities have planned and executed CDR management to this day. The side effects of this situation are plainly visible: the refuses have been continually and irregularly deposed in unused areas, thoroughfares, riversides, creeks and even in environmental protection areas, causing the proliferation of health-affecting problems, flooding and many other damages to the environment. Therefore, this study has the main goal of proposing solutions that can lessen the environmental impact by using CDR as aggregate in the manufacturing of concrete blocks. The lab tests and the comparing of the results obtained with those measured with the conventional techniques prove the viability of reutilizing these refuses, both in environmental and economical terms, as well as assuring that the use of CDR follows all the current regulations. With this, the compromise with environmental preservation is reinforced, since the recycling this type of refuse, beside helping to remove it from the urban landscape, generates considerable gains in saving energy and the non-renewable natural resources that would be used as raw material, lessening air, water and soil pollution, releasing the burden on landfills, always aiming at achieving sustainable development.

Orientador: Osvaldo Luís Manzoli / Resumo: Este trabalho apresenta uma proposta de análise numérica do concreto com agregados reciclados (CAR). A ferramenta desenvolvida facilita a avaliação do comportamento mecânico do material, verificando a viabilidade de sua utilização para fins estruturais. Considerando que no Brasil o emprego atual do material ainda é bastante limitado em comparação com outros países, o CAR pode vir a ser utilizado mais ampla e adequadamente, trazendo vantagens de caráter estrutural, econômico, e principalmente ambiental. Em termos de modelagem do CAR, a ocorrência de particularidades em nível mesoscópico exige um modelo em escala mais refinada para representar as propriedades alteradas do agregado reciclado (AR), de modo que foi desenvolvido um gerador de agregados reciclados para representar sua composição variada. Os mecanismos de falha que ocorrem nas interfaces características do agregado reciclado e da matriz de concreto introduzem não linearidade ao problema mecânico. Para que haja a representação dessa não linearidade, a estratégia de modelagem proposta recorre ao emprego da técnica de fragmentação de malha de elementos finitos juntamente com um modelo constitutivo de dano. Essa técnica de fragmentação baseia-se no emprego de elementos finitos com alta razão de aspecto, os quais poderão ser utilizados para representar as fases adicionais desse material compósito, correspondentes às diferentes zonas de transição interfaciais (ZTIs) intrínsecas do CAR em mesoescala, e consequentemente, cam... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This research presents a numerical analysis proposal for recycled aggregate concrete (RAC), whose recycled aggregates are obtained from the crushing of concrete waste. The developed tool facilitates the mechanical behavior evaluation of the RAC, verifying the feasibility of its use for structural purposes. Considering that in Brazil the current use of the material is still quite limited in comparison with other countries, the RAC could be used more widely and properly, bringing structural, economic and mainly environmental advantages. Due to the occurrence of mesoscopic specificities, the RAC modeling requires a more refined scale model to represent the altered properties of recycled aggregate, so that a recycled aggregate generator was developed to represent its variable composition. The failure mechanisms that occur at the several interfaces of the recycled aggregate (RA) and concrete matrix introduce nonlinearity to the mechanical problem. In order to represent this nonlinearity, the proposed modeling strategy uses the finite element mesh fragmentation technique together with robust and stable damage constitutive model. This fragmentation technique is based on the use of finite elements with high aspect ratio, which can be used to represent the additional phases of this composite material, corresponding to the different mesoscale RAC intrinsic interfacial transition zones (ITZs), as well as potential pathways for the propagation of fractures. A constitutive model based on ... (Complete abstract click electronic access below) / Mestre

Due to a European energy concept for reducing energy consumption and also the concept of sustainable development, there is a growing demand for reduced energy consumption during the operation of the building and hence increasing demands on the thermal and mechanical properties of the building envelope. For this reason, it is necessary to look for materials that could meet both thermal and mechanical properties, as well as mechanical resistance and loadability, especially for the application for the foundations of the house, the base of the house and for application to structural details for elimination of the thermal bridges between interior and exterior boundaries. The main motivation for choosing the topic of thesis was to find materials derived from recycled or secondary raw materials that would be suitable for manufacturing composite applicable for structural details in the envelope of the building and for insulating in humid environment. An economic and environmental aspect plays an important role in the choice of material. The main theme of the thesis is the laboratory manufacturing of a composite with a thermoplastic matrix derived from recycled plastic materials and waste foam as a phase. Has been developed a unique Waste-based Particle Polymer Composite (WPPC) made from recycled foam and polypropylene. However, before WPPC can be reliably used by construction designers, physical properties of WPPC must be accurately identified. Therefore, it was designed laboratory manufacturing system and sample testing system, it was studied thermal, mechanical, thermomechanical and moisture absorptivity of WPPC. Application of finished composite material with satisfying thermal insulation properties to structural details to eliminate the thermal bridge, was the next step. These are details of the unloaded, prefabricated balconies, windows, atics, as well as basement constructions and the heel of the central load-bearing wall, the terrain flooring and the staircase wall

The diploma thesis deals with the use of recycled polymers in asphalt mixtures. In the theoretical part of the thesis there is discussed the global issue of plastic waste including the experience of foreign countries, where this technology has already been introducted and used. The practical part is devoted to the proposal of using recycled plastic in asphalt mixture, description of used laboratory tests and the evaluating the effect of low-density polyethylen (LDPE) on the asphalt mixture type AC. There were performed tensile strenght tests, water resistant tests and stiffness modulus tests in the laboratory (E). The output of this work is an evaluation of measured values, processing of results and their interpretation depending on the possible use of this technology in Czech republic.

This thesis addressed the development renders the optimal ratio of thermal insulation and mechanical properties. In developing these materials were used alternative latent hydraulic binders. Research was conducted plasters and renders the requirements of technical standards in the Czech Republic. Work dealt with the general composition of plaster, including the use of secondary raw materials in dry plaster mixtures and thermal insulation properties and remediation plaster. Furthermore, the measured values of physical and mechanical properties of the test formulations. The best recipes were compared with plaster on the Czech market.

This thesis deals with compares the procedures carried out in the cyclical load triaxial testing device according to CSN EN 13286-7, and the procedures performed in the United States of America. In the practical part elasticity moduls of mixed recycled material are experimentally compared with mixed recycled material containing binder(connective material) and with fine-grained soil in the cyclical load triaxial testing device. Further the thesis assesses the use of mixed recycled material in the construction of a third class low-load pavement.

The theoretical part of this master’s thesis contain comparing the methods of endurance hydraulic bound mixtures of concrete recycles against influence of water and freeze in Czech republic and some other states of The European Union. The practical part is dedicated about laboratory testing concrete recycles with mixtures of binders and its endurance against the water and freeze cycles in Czech republic. In made rollers is compared the strength in pure compression with the strength in pure compression after freezing cycles. From the results of the exams is considered about suitability of using these hydraulic bound mixtures to road construction depending on the kind of use binder, amount of the binder and water. Results of this thesis will be used to revision of national postscript of technological norm ČSN 73 6124-1.

In manufacture of cement-bonded particle boards are in present-days used exclusively wooden particles as filler. This thesis deals with a research of possible substitution of this material, especially of waste emerging by production of CBPB itself. At first is completed a survey of possible substitute fillers and czech and foreign literature, dealing with issues of modification of composition of cement-bonded particle boards. In practical part are tested some treatments of waste and its adding to recipe. Further are analysed the influences of substitution of cement by slag and substitution of wooden particles by recycled fibreglass. By laboratory work with CBPB is monitored the influence of amounts of added wather to fresh mixture and also to properties of finished elements.

Master's thesis consists of two parts, theoretical and practical. In the theoretical section are listed basic information about alternative aggregates used for concrete mixture, like polystyrene, cinder and recycled concrete. Further, the influence of these alternative aggregates, used as secondary raw materials, on the behaviour and properties of fresh respectively hardened concrete. Possibilities of application concrete containing secondary raw materials are mentioned. In the practical part are experimentally verified physical and mechanical properties of concrete containing crushed waste polystyrene beads, furthermore thermal insulation properties and resistance to elevated temperatures is tested. Influence of heating plant cinder powder as active addition to concrete mixture was tested. As a next is prepared concrete with replacement of coarse aggregate by cinder and recycled concrete and tested. The influence of these secondary raw materials on workability, compressive strength, frost resistance and water permeability of concrete is also defined. The last part of research is focused on recycled concrete such as main material used in mixture of aggregates bonded with cement, dispose for base layers in roads. In conclusion are discussed results from experimental research and summary of knowledge’s about using polystyrene, cinder and recycled concrete as aggregates for concrete mixtures.

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