O uso de resíduos de construção e demolição (RCD) vem ganhando espaço crescente em aplicações na engenharia. Este material adquiriu maior importância a partir da década de 70, com seu emprego ampliado como material granular em concretos de cimento para obras civis e no setor de infraestrutura, principalmente como camadas de pavimentos. O presente trabalho tem por objetivo compreender o comportamento físico e mecânico do agregado reciclado de resíduos de construção e demolição com adição de aglomerantes, a cal hidratada e cimento Portland. Foram construídos três trechos experimentais de uma via urbana com uso de RCD misto na sub-base dos pavimentos: (i) um sem aglomerantes adicionais, (ii) um com adição em usina de 3% de cal hidratada, e (iii) um com adição em usina de 3% de cimento Portland. Todas as amostras coletadas em usina foram caracterizadas em laboratório e foram analisados os comportamentos mecânicos das três diferentes misturas por meio de ensaios de (i) resistência à compressão simples aos 7 dias de cura para os materiais com aglomerantes, (ii) ensaios de módulo de resiliência a 7, 28 e 60 dias de cura para todas as misturas, e (iii) ensaios de deformação permanente com diferentes tensões. Analisando os resultados das misturas a 60 dias de cura, a mistura em RCD apresentou com o menor ganho em módulo de resiliência, enquanto que a mistura de RCD com 3% cimento, apresentou os maiores módulos, e a mistura RCD com adição em 3% de cal obteve um valor pouco abaixo daquele com cimento. Quanto ao comportamento à deformação permanente, verificou-se que a baixos níveis de tensão, todas as misturas apresentaram baixas deformações e comportamento similar. Em maiores níveis de diferença de tensões principais, as misturas estabilizadas apresentaram comportamento estável e as misturas em RCD obtiveram deformação permanente mais significativa. Com o monitoramento deflectométrico foi possível realizar retroanálise, e estimar os módulos de resiliência in situ, cujos valores foram similares aos encontrados em laboratório. Passados quase dois anos, o comportamento funcional e estrutural dos trechos experimentais é satisfatório. / The use of construction and demolition waste (CDW) has been increasing in engineering applications the use of CDW has become more important since the 70s as granular material in cement concrete applications in civil engineering and transportation infrastructure, mainly as pavement layers. This study aims to understand the physical and mechanical behavior of recycled aggregate from construction and demolition waste with the addition of hydraulic binders, as hydrated lime and Portland cement. Three experimental urban pavement sections were constructed using CDW as subbase material: (i) the first one using CDW, (ii) the second one using CDW with 3% of hydrated lime (mixed in the plant), and (iii) the third one employing CDW with 3% of cement (also mixed in the plant). All samples collected in the plant were characterized in laboratory. The mechanical behavior of these materials and mixtures were analyzed through the following tests: (i) compressive strength after 7 days of curing for materials with hydraulic binders, (ii) resilient moduli after 7, 28, and 60 days of curing for all mixes, and (iii) permanent deformation. By analyzing the responses of the mixture after 60 days of curing, the CDW mixture presented, as a crushed stone, the smallest gain on resilient modulus, whereas mixture with 3% cement with CDW had the highest modulus. The mixture with 3 % hydrated lime with CDW showed resilient modulus smaller than the mixture with cement. The permanent deformations at low stress levels were low and similar for the three tested materials. On the other hand, at higher stress level, the stabilized mixtures exhibited stable behavior, and the mixture with CDW shows a significant permanent deformation. The backcalculation based on the measurement of field deflections showed values of resilient moduli in situ similar to the laboratory results. After almost two years, the performance of the experimental sections is considered satisfactory.

No / Degrading infrastructure and applications of structural demolition create tremendous amounts of construction and demolition waste (CDW) all around the world. To address this issue in an effective way, recycling CDW in a most appropriate way has become a global concern in recent years. To this end, this study focused on the utilization of CDW-based materials such as hollow brick (HB), red clay brick (RCB), roof tile (RT), glass (G) and concrete (C) in the production of geopolymer mortars. These materials were first collected from an urban transformation area and then subjected to an identical two-step crushing-milling procedure to provide sufficient fineness for geopolymerization. To investigate the influence of blast furnace slag (S) addition to the CDW-based mixtures, 20% S substituted mixture designs were also made. Fine recycled concrete aggregates (FRCA) obtained from crushing and sieving of the waste concrete were used as the aggregate. A series of mixtures were designed using different proportions of three distinct alkali activators such as sodium hydroxide (NaOH), sodium silicate (Na2SiO3) and calcium hydroxide (Ca[OH]2). To improve their applicability, the mixtures were left to cure at room temperature rather than the heat curing which is frequently applied in the literature. After 28 days of ambient curing, the 100% CDW-based geopolymer mortar activated with three different activators reached a compressive strength of 31.6 MPa, whereas the 20% S substituted geopolymer mortar achieved a compressive strength of 51.9 MPa. While the geopolymer mortars activated with only NaOH exhibited poor performance, it was found that the use of Na2SiO3 and Ca(OH)2 improved the compressive strength. Main geopolymerization products were related to NASH, CASH, and C(N)ASH gel formations. Our results demonstrated that mixed CDW-based materials can be employed in the manufacturing geopolymers, making them potential alternatives to Portland cement-based systems by being eco-friendly, energy-efficient, and comparable in compressive strength. / This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 894100.

Yes / Demolition and reconstruction of degrading structures alongside with the repetitive repair, maintenance, and renovation applications create significant amounts of construction and demolition waste (CDW), which needs proper tackling. The main emphasis of this study has therefore been placed on the development of concrete mixtures with components (i.e., aggregates and binder) coming entirely from CDW. As the binding phase, powdered CDW-based masonry units, concrete and glass were used collectively as precursors to obtain geopolymer binders, which were then incorporated with CDW-based fine and coarse concrete aggregates. Together with the entirely CDW-based concretes, designs were also proposed for companion mixtures with mainstream precursors (e.g., fly ash and slag) occupying some part of the CDW-based precursor combination. Sodium hydroxide (NaOH), sodium silicate (Na2SiO3) and calcium hydroxide (Ca[OH]2) were used at various concentrations and combinations as the alkaline activators. Several factors that have impact on the compressive strength results of concrete mixtures, such as mainstream precursor replacement rate, al-kaline molar concentrations, aggregate-to-binder ratios and curing conditions, were considered and these were also backed by the micro-structural analyses. Our results showed that through proper optimiza-tion of the design factors, it is possible to manufacture concrete mix-tures entirely out of CDW with compressive strength results able to reach up to 40 MPa under ambient curing. Current research is believed to be very likely to promote more innovative and up-to-date techniques to upcycle CDW, which are mostly downcycled through basic practices of road base/sub-base filling, encouraging further research and increas-ing the awareness in CDW issue. / The full-text of this paper will be released for public view at the end of the publisher embargo on 1 Jul 2024.

Yes / Geopolymers are mostly produced with main-stream precursors such as fly ash and slag. These precursors are successfully used and competitively demanded by the cement industry. Development of geopolymers from alternative precursors is appealing. The main aim of this work is the development of geopolymers with construction and demolition waste-based precursors including masonry units (red clay brick, roof tile, hollow brick) and glass. Different curing temperatures (50, 65, 75, 85, 95, 105, 115, 125 oC), curing periods (24, 48, 72 h), and Na concentrations (10, 12, 15%) of alkaline activator (NaOH) were employed. Compressive strength testing and microstructural investigations were performed including X-ray diffraction, thermogravimetry and scanning electron microscopy with energy-dispersive X-ray spectroscopy. Results showed that depending on the type of precursor (hollow brick), curing temperature/period (115 oC/24 h) and concentration of alkaline activator (12%), it is possible to obtain compressive strength results more than 45 MPa. Hollow brick is the most successful precursor resulting in higher compressive strength results thanks to a more compact microstructure. The strength performance of red clay brick and roof tile is similar. The compressive strength results of geopolymers with glass precursor are lower, most probably due to significantly coarser particles of glass used. The main reaction products of red clay brick-, roof tile- and hollow brick-based geopolymers are sodium aluminosilicate hydrate (N-A-S-H) gels with zeolite-like structures while they are sodium silicate gels in the case of glass-based geopolymers. Our findings showed that CDW-based materials can be used successfully in producing geopolymers. Current research is believed to help raise awareness in novel routes for the effective utilization of such wastes which are realistically troublesome and attract further research on the utilization of CDW-based materials in geopolymer production. / The authors gratefully acknowledge the financial assistance of the Scientific and Technical Research Council (TUBITAK) of Turkey and British Council provided under projects: 117M447 and 218M102.

Construction and Demolition (C&D) wastes are materials produced in the process of construction, renovation, or demolition of structures (buildings and roads). It also includes materials generated as a result of natural disasters (EPA, 2009). Preliminary estimates from the U.S. Environmental Protection Agency (EPA) show that the nation generated more than 160 million tons of building related C&D wastes in 2003. Also, Pennsylvania Department of Environmental Protection (PADEP) estimated that in 2005, Pennsylvania disposed over 2.25 million tons of C&D wastes in its municipal and C&D landfills (PADEP, 2009).Though previous studies have shown that it is cost-effective and environmentally friendly for contractors or construction managers to recycle C&D wastes rather than disposing them in landfills, these previous studies, however, paid little or no attention to detailed cost of recycling C&D wastes in a particular geographical area or region as compared to the availability of market for recycled materials or monetary value of the recycled materials. Hence, the objective of this study was to develop a mathematical model that helps stakeholders in construction business to evaluate the potential cost of recycling C&D waste components in their geographical area or region, and the potential revenue from the recycled materials. The model developed in this thesis will enable private companies or individuals to identify, invest and participate in the recycling of C&D waste components that yield good profits in their region or area. It will also enable Government to identify, sponsor or provide incentives for the recycling of C&D waste components that yield no or less profit in order to reduce environmental pollution and generate jobs. A case study is conducted in Pennsylvania to test the model developed in this thesis and the test has been successful. Based on the mathematical model and logic structure for selecting C&D waste components for recycling, drywall, roofing shingles and wood are identified as the components whose recycling will yield good profit and thus may not need government's support or incentives. Moreover, C&D waste components such as concrete, brick, block and asphalt, have been identified as components whose recycling will not be profitable enough and therefore would require government's support or incentives. The result of the case study also shows that the quantity of non-ferrous metals in C&D wastes are very small and their recycling will not yield any significant profit. / Civil Engineering

Yes / Degrading infrastructure and applications of structural demolition create tremendous amounts of construction and demolition waste (CDW) all around the world. To address this issue in an effective way, recycling CDW in a most appropriate way has become a global concern in recent years. To this end, this study focused on the valorization of CDW-based materials such as tile, bricks, glass, and concrete in the development of geopolymer mortars. CDWs were first collected from demolition zone and then subjected to crushing-milling operations. To investigate the influence of slag (S) addition to the mixtures, 20% S substituted mixture designs were also made. Fine recycled concrete aggregates (FRCA) obtained from crushing and sieving of the waste concrete were used as the aggregate. A series of mixtures were designed using different proportions of three distinct alkali activators such as sodium hydroxide (NaOH), sodium silicate (Na2SiO3), and calcium hydroxide (CH; Ca(OH)2). To improve their applicability, the mixtures were left to cure at room temperature rather than the heat curing which is frequently applied in the literature. After 28 days ambient curing, the 100% CDW-based geopolymer mortar activated with three different activators reached a compressive strength of 31.6 MPa, whereas the 20% S substituted geopolymer mortar showed a 51.9 MPa compressive strength. While the geopolymer mortars activated with only NaOH exhibited poor performance, it was found that the use of Na2SiO3 and CH improved the mechanical performance. Main geopolymerization products were related to NASH (Sodium alumino-silicate hydrate), CASH (Calcium alumino-silicate hydrate), and C(N)ASH gel formations. Results demonstrated that mixed CDWs can be employed in the manufacturing geopolymers, making them potential alternatives to Portland cement (PC)-based systems by being eco-friendly, energy-efficient, and comparable in compressive strength. / This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 894100.

The construction and demolition (C and D) recycling industry creates economic opportunity through business activity; promotes equity through workforce training and partnerships; and helps to conserve natural resources through the reuse, remanufacturing, and recycling of C and D debris. While C and D recycling satisfies traditional local economic development goals, it also addresses broader goals of progressive, and sustainable local economic development. The general planning literature shows an increasing interest in sustainability; however, there have been fewer studies on sustainable local economic development initiatives. This research examines the current state of local economic development agency support for the C and D recycling industry as an economic development strategy. In doing so, the dissertation assembles the array of activities local economic development agencies used to support the industry; identifies distinguishing policy or contextual characteristics of agencies that actively supported the industry from those that did not; and assesses whether the agencies support for C and D recycling fit within the rational planning model. Using data from a national survey of local economic development agencies, the study categorizes the local economic development tools used to support the industry. Results show that a combination of traditional, progressive, and sustainable local economic development tools are adapted and newly created to satisfy the specific needs of this specialized industry. Multiple discriminant analyses identify key characteristics of the agencies that support C and D recycling. These characteristics include previous support for the general recycling industry, the presence and support of environmental enterprise zones and eco-industrial parks, and knowledge of local landfill capacity issues. Overall, the agencies that actively supported C and D recycling engage in activities associated with sustainable local economic development. The descriptive and statistical analyses are combined with the surveys qualitative responses to determine that local economic development agencies do not operate under a strict interpretation of the comprehensive rational planning model in their support of C and D recycling. Instead, local economic development agencies use modified rational and reactive planning strategies in their support of the industry. The study concludes with policy recommendations to increase local economic development agency support for C and D recycling.

Submitted by Maike Costa (maiksebas@gmail.com) on 2017-10-03T11:33:15Z No. of bitstreams: 1 arquivototal.pdf: 3170454 bytes, checksum: 4df0811997519669118a21ed7a252651 (MD5) / Made available in DSpace on 2017-10-03T11:33:15Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3170454 bytes, checksum: 4df0811997519669118a21ed7a252651 (MD5) Previous issue date: 2016-03-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Waste resulting from the construction industry have a significant negative environmental impact, thus being a major problem for the construction industry and the regulatory agencies. The minimization of this waste can occur if they are properly managed from its generation to its final disposal, contributing to the reduction of environmental degradation. This research presents the results of the verification of the performance of the components of the RCD flow (generator - transporter - receiver for final disposal) regarding establishing legislation in the João Pessoa city. The aim of this study is to verify the compliance percentage (level of service) the final disposal stage of RCD flow in relation to the provisions of the legislation. The study presents the adherence percentage for the two companies officially responsible for the final disposal of this region, namely the USIBEN (RCD processing plant) which showed 79% of adherence and the Landfill Metropolitan which showed 63% adherence. The results show deviations in the treatment of RCD in relation to what is provided in legislation, especially to waste class D, which are considered dangerous, as well as other points that can and should be improved. / Os resíduos resultantes da indústria da construção civil têm um impacto ambiental negativo relevante, sendo assim um grande problema para o setor da construção civil e para os órgãos fiscalizadores. A minimização destes resíduos pode ocorrer se os mesmos forem corretamente gerenciados desde sua geração até sua disposição final, contribuindo para a diminuição da degradação do meio ambiente. Esta pesquisa apresenta os resultados da verificação da atuação dos componentes do fluxo de RCD (gerador – transportador – receptor para disposição final) em relação ao disposto na legislação na cidade de João Pessoa. O objetivo geral deste trabalho é verificar o percentual de aderência (nível de atendimento) da etapa de disposição final do fluxo de RCD em relação ao disposto na legislação. O estudo apresenta o percentual de aderência para as duas empresas oficialmente responsáveis pela disposição final desta região, qual seja, a USIBEN (usina de beneficiamento de RCD) que apresentou 79% de aderência e o Aterro Metropolitano que apresentou 63% de aderência. Os resultados demonstram desvios no tratamento de RCD em relação ao que está disposto na legislação, especialmente para com os resíduos classe D, que são considerados perigosos, além de outros pontos que podem e devem ser melhorados.

ABSTRACT Sustainable development has become part of Government policy across the world. In the construction industry it has been introduced through the promotion of “sustainable construction” or “green construction”. International trends show a gradual move away from wasteful construction industry practices that include high resource consumption, material wastage, inefficiencies in construction processes and a high percentage of waste that find its way to waste disposal sites and illegal dumps. This research report seeks to promote sustainable construction and waste minimisation as preferred models for achieving a balance in the economic, social and environmental impacts of development. It reviews South Africa’s construction and demolition site practice from the perspective of construction and demolition waste management, assessing waste management practice and the resultant waste disposal. To gauge South Africa’s performance it benchmarks South African practice against those of the United States, United Kingdom, Germany and the Netherlands. This approach highlights gaps in South Africa’s current practice and also provides some valuable lessons that can be used to ensure compliance with sustainable construction principles. Finally the research report proposes a framework for developing a self-sustaining secondary construction materials market in South Africa, which can prove to be a valuable tool for ensuring the absorption of sustainable construction in the construction industry.

Esta pesquisa propõe uma metodologia para avaliar o potencial de reciclagem de resíduos e indicar as aplicações mais sustentáveis, considerando aspectos econômicos, de mercado, ambientais e de risco à saúde humana. A idéia central é avaliar o uso do resíduo baseado em suas características e propriedades físico-químicas e, a partir disso, identificar áreas potenciais que possam absorvê-lo da forma mais sustentável possível. A avaliação da aplicabilidade foi realizada com base em requisitos identificados por especialistas de diversas áreas. A metodologia foi testada para avaliar o potencial de reciclagem dos resíduos de tratamento de esgoto e dos resíduos de construção e demolição (RCD). / This research suggests a methodology to evaluate the recycling potential of waste products and to indicate the most sustainable applications regarding economical, market, environmental and hazard to human health aspects. The main idea is to evaluate the use of the waste based on its physico-chemical characteristics and properties, and then, to identify potential areas to absorb them, through sustainable processes. The evaluation of the applicability has been based on requirements identified by specialists from several areas. The methodology has been applied to evaluate the recycling potential of sewage sludge wastes and construction and demolition wastes (CDW).