This article demonstrates the potential use of residual sand removed from grit chambers, which are used in the primary treatment of Wastewater Treatment Plants (WWTPs), as an alternative material to commercial sand in the production of non-structural concrete in civil construction. The results indicated that the residual sand has a high percentage of total fixed solids (96.9%), high moisture content (14.8%) and significant total coliform [average of 3.84 × 107(100 mL)−1] and fecal coliform densities [average of 5.22 × 105 (100 mL)−1]. The sand cleaning and drying procedure used in the research was effective, since it achieved the following removal efficiencies: about 98.8% of moisture, 67.1% of total volatile solids and 4-log E. coli. After cleaning and drying the residual sand, different amounts of this material were used to prepare the test specimens, which underwent tensile tests. The results of this study confirmed the viable use of residual sand as fine aggregate in concrete for non-structural purposes, and the best performances were verified in tensile and compressive tests (fck) and tensile strength tests (fctk) using 30% (in mass) of the residual sand as fine aggregate (values of 16.6 and 1.60 MPa, respectively).

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RESUMOConsiderando uma crescente preocupação quanto à possibilidade de limitação de recursos naturais disponíveis para a produção de bens materiais, os efeitos das mudanças climáticas decorrentes da degradação do meio ambiente e a importância do emprego de materiais locais de fontes renováveis na produção de produtos "mais" sustentáveis, o trabalho visa contribuir para a utilização de madeira de lorestas plantadas na arquitetura e construção civil. O objetivo é demonstrar o caráter sustentável da madeira de lorestas plantadas como material construtivo para utilização em interfaces de componentes estruturais pré-fabricados. A metodologia visou a apresentação do caráter sustentável da madeira de lorestas plantadas; levantamento acerca da madeira de lorestas plantadas no Brasil, deinição de sistemas construtivos com componentes pré-fabricados em madeira e; propostas de interfaces entre componentes estruturais. Como resultados foi demonstrada a viabilidade de utilização da madeira de lorestas plantadas para a construção civil, levando em consideração, principalmente sua viabilidade técnica e os aspectos sustentáveis de sua utilização. ABSTRACTWhereas a growing concern about the possibility of limitation of available natural resources for the production of material goods, the efects of climate change resulting from degradation of the environmental and the importance of the use of local materials from renewable sources in the production of products "more" sustainable, the study aims to contribute to the use of wood from planted forests in architecture and construction. Objective: To demonstrate the sustainable character of wood from planted forests as a building material for use in interfaces of structural components pre-manufactured. The methodology aimed to presentation of the sustainability of the use of wood from planted forests; survey about the wood from planted forests in Brazil; deinition of construction systems with components pre-manufactured in wood and; proposals for interfaces between structural components. As results was demonstrated the viability of using wood from planted forests for civil construction taking into consideration especially its technical feasibility and sustainable aspects of their use.

Inte rnat iona l Jour nal of En vir on me nt an d Su sta ina ble De ve lo pm en t

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