Reinsertion of construction and demolition waste into the production chain of civil construction in Rio Branco, Acre

The environmental, economic and social impacts caused by construction and demolition waste (CDW) in the city of Rio Branco (capital of Acre, Federal State of the Amazon region) in line with the scarcity of aggregate deposits and the social demands for paving and housing for civil construction makes the production and use of recycled aggregates an alternative of great interest. In this scenario, this study evaluated the technical, economic and environmental feasibility of recycling CDW for purposes of application in paving and civil construction. For this, periodic and systematic visits were carried out to the construction sites to formulate the representative indexes of the generation and composition of the CDW, economic feasibility analysis of the recycling plant, discussions on the environmental impact on the inert landfill, waste collection in works in the phases of structures, masonry and finishing for the production of recycled aggregates evaluated in 10 different compositions, performing technological tests of requirements in order to obtain the physical and mechanical properties for application in cementitious matrices of Portland cement and pavement structure, evaluation of the insertion of recycled aggregate in the priority social demands for civil construction (housing) and heavy construction (paving infrastructure), verification of the current management of the CDW and elaboration of actions and guidelines, recycling policies and proposed goals to be achieved in order to promote an effective management and effective CDW. Among the results, it was found a generation of CDW per built area of 0.22 t/m2 for new constructions and 0.41 t/m2 for renovations, where 100% of the CDW was considered reusable and/or recyclable. Economic indicators showed the feasibility of installing a recycling plant with a processing capacity of 90 t/h. Environmental impacts will no longer occur in the inert landfill with the implementation of the recycling plant. Recycled CDW aggregates in the form of sand, gravel, gravel, crack and running spout proved to be technologically viable for safe application in mortar, concrete and layers of pavement structures, presenting satisfactory properties and even better than conventional ones. The city demands the construction of up to 46 thousand houses and the paving of 550.5 km of production routes for the primary sector. Actions and guidelines, recycling policies and targets are necessary for the correct management of the CDW, including specific legislation with mandatory compliance, mandatory screening at the origin of generation with payment of deposition fee, mandatory use of recycled aggregates in public works , tax incentives for the installation of enterprises dedicated to recycling, hiring career inspectors for inspection actions, adoption of sustainability seals that certify civil construction companies and establishment of social quotas for recycled aggregates for low-income families and application in production routes of the primary sector. Thus, the proposed reinsertion of CDW in the production chain is of great interest for the Amazonian civil construction, considering the scarcity, the high costs of raw materials and the need to define and consolidate a sustainable development model for the Amazon region.