The recycled aggregates of construction and demolition solid waste can be used on pavements to decrease environmental impacts in cities. Thus, this study aimed to compare the mechanical performance of asphaltic mixtures made with natural aggregates and concrete recycled aggregates for surface course of pavements. The materials were collected in an asphalt mixing plant and in a construction and demolition solid waste recycling plant located in João Pessoa/PB, Brazil. The Marshall asphalt mix design was chosen to determine optimum asphalt content and evaluate mechanical performance of asphaltic mixtures. The asphalt mixtures specimens were composed of natural aggregates, and afterwards of recycled aggregates with percent contents of 25, 50 and 100. The optimum asphalt contents were 5.7 and 7.5%, Marshall stability of 1,070 and 790 Kgf, flow of 6.2 and 5.7 mm for natural aggregate asphalt mixtures and asphalt mixtures with 25% recycled aggregates, respectively. Moreover, percent air voids and percent voids filled with asphalt met the Brazilian DNIT: ES 031/2006 specified standard. However, the asphalt mixtures with 50 and 100% recycled aggregates did not meet the specified standard. Therefore, it was concluded that the replacement of natural aggregates with 25% recycled concrete aggregates in asphalt mixtures can be technically viable to build asphalt surface course on pavements, besides lowering pavement costs and decreasing environmental impacts.

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The production of municipal waste is increasing all over the world. Although a significant part of the waste is collected as commingled waste, much of it is recyclable if disposed of properly. Thus, separate deposition and collection plays an extremely important role today, more than ever, not only in terms of preventing pollution but also from the point of view of recycling as a driver of circular economy and of efficient use of resources. This work is focused on the development of compaction equipment to be applied to containers, which allows a more efficient approach to the process of collecting waste for recycling. As a management option, recycling depends on collective behavior which is based on individual acts. Therefore, individual use of plastic/metal compaction systems can help meet recycling targets, even as a complement to conventional bins. Thus, herein a proposal is presented for a plastic/metal collection station with a built-in compaction element that allows for the compacting of the separated waste, individually, in an easily accessible drawer. Sorting and compacting waste before collection will result in a reduction of the number of collection/transport stops, which will also translate into higher energy efficiency, cost savings, optimization of the transported tons/km ratio, and profitability.

O objetivo deste artigo é apresentar e discutir o estado da arte sobre as motivações dos cidadãos para a Coprodução do Bem Público (CBP). O propósito é identificar os diversos aspectos que motivam os cidadãos a se envolverem na CBP, seja em parceria com o Estado ou com organizações da sociedade civil, bem como permitir a geração de novos conhecimentos a partir destes aspectos. Como metodologia, a pesquisa utilizou a revisão integrativa da literatura, mediante análise de conteúdo categorial, com a finalidade de reunir e sintetizar os resultados de pesquisas que abordam aspectos que motivam o cidadão a ser coprodutor do bem público. Os aspectos motivacionais apresentados na matriz de síntese apontam as diferentes motivações para o cidadão participar da CBP, deixando latente a complexidade do tema e o quão difícil é propor um modelo de tamanho único, pois diferentes formas de coprodução podem exigir estratégias diferentes para engajar o público. Listar estes aspectos é relevante aos gestores públicos e de organizações da sociedade civil, pois poderão nortear as estratégias a serem utilizadas no engajamento do cidadão na CBP. Assim, eles devem adotar diferentes estratégias quanto ao envolvimento dos cidadãos na CBP, levando em consideração que cada participante é único e tem motivações diferentes. Baseando-se nos aspectos analisados, são apresentados questionamentos que contribuem para a formação de uma agenda de pesquisa, bem como auxiliam gestores públicos interessados na coprodução do bem público como estratégia de gestão.