ABSTRACT Currently, mining waste has been take an important role as a raw material in environmental sustainability programs, with the objective of minimizing the impacts resulting from mining activity. Given this, this research proposes to analyze pegmatite mining waste for use in aggregate for concrete. The samples were petrographically characterized according to their reactive potential to the Alkali-Aggregate Reaction under standard ABNT 15577-3 and tests were performed to evaluating the physical indexes and mechanical strength. It was found among the dimensions of pegmatites that two of them shows innocuous for alkali-aggregate reaction, because it contains levels of deleterious phases for RAA below the limit acceptable by the norm. Though, the other samples showed potential reactivity to RAA, because either contains deformed quartz, or both deleterious phases identified according to the standard used: deformed quartz and microgranular. The mechanical resistance assumed values below the average values presented by the consulted literature. This fact is justified by the degree of alteration observed in the studied samples. Mining residues were found to have been subjected to weathering, resulting in a drop in expected mechanical strength values. Considering the physical indexes, the samples showed good results regarding the moisture absorption capacity.

ABSTRACT Currently, mining waste has been take an important role as a raw material in environmental sustainability programs, with the objective of minimizing the impacts resulting from mining activity. Given this, this research proposes to analyze pegmatite mining waste for use in aggregate for concrete. The samples were petrographically characterized according to their reactive potential to the Alkali-Aggregate Reaction under standard ABNT 15577-3 and tests were performed to evaluating the physical indexes and mechanical strength. It was found among the dimensions of pegmatites that two of them shows innocuous for alkali-aggregate reaction, because it contains levels of deleterious phases for RAA below the limit acceptable by the norm. Though, the other samples showed potential reactivity to RAA, because either contains deformed quartz, or both deleterious phases identified according to the standard used: deformed quartz and microgranular. The mechanical resistance assumed values below the average values presented by the consulted literature. This fact is justified by the degree of alteration observed in the studied samples. Mining residues were found to have been subjected to weathering, resulting in a drop in expected mechanical strength values. Considering the physical indexes, the samples showed good results regarding the moisture absorption capacity.

ABSTRACT Detention reservoirs waters are generally not used productively and their potential is wasted. By their scattered location in the cities, their use can decrease water transport costs, and also allow water to be preserved for higher quality water uses. Some of their possible uses are irrigation of green areas, use in boilers, cooling towers and other industrial uses, in soil compaction, cleaning of public areas, in pisciculture, in fire fighting systems, etc. The improper dumping of water sewage into the drainage system influences the quality of this water. The study was performed in six infiltration and detention reservoirs of the Natal drainage system, northeastern Brazil, to verify the non-potable use condition of these waters in the urban environment. It was observed that some reservoir waters were compatible to be used in pisciculture and cooling towers and others require previous treatment, to decrease, mainly, pathogenic organisms before being used.

ABSTRACT Detention reservoirs waters are generally not used productively and their potential is wasted. By their scattered location in the cities, their use can decrease water transport costs, and also allow water to be preserved for higher quality water uses. Some of their possible uses are irrigation of green areas, use in boilers, cooling towers and other industrial uses, in soil compaction, cleaning of public areas, in pisciculture, in fire fighting systems, etc. The improper dumping of water sewage into the drainage system influences the quality of this water. The study was performed in six infiltration and detention reservoirs of the Natal drainage system, northeastern Brazil, to verify the non-potable use condition of these waters in the urban environment. It was observed that some reservoir waters were compatible to be used in pisciculture and cooling towers and others require previous treatment, to decrease, mainly, pathogenic organisms before being used.

ABSTRACT In civil construction, a recurring environmental problem is the generation and disposal of Construction and Demolition Waste (RCD) of works. The use of RCD as aggregates of pre-mixed mixed asphalt concrete (PMF) makes possible the implementation of low traffic pavements. Therefore, this article proposes to evaluate the technical feasibility of the recycled materials, through laboratory tests and dosages of asphalt concrete, replacing natural aggregates by recycled in mixtures of asphalt concrete to be used as floor covering layer. In the research, analyzes of physical characterization of the material were carried out; mineralogical characterization of the RCD filler (DRX, FRX, EDS and MEV); and analyzes of Marshall's dosages of asphalt concrete (Pre-mixed to PMF) varying in asphalt emulsion contents in 6%, 7%, 8% and 9%, in each mixing design. The FRX results indicated oxides such as SiO2, Fe2O3 and Al2O3, with significant silica, iron and aluminum contents, also characterizing the predominantly ceramic origin of the RCD material. Analyzing Marshall methodology parameters, the interaction of emulsion contents with Stability, Void Volume, Density, and Empty Bitumen properties showed lower performance of concrete with RCD aggregates, however, consistent with the Marshall standard parameters of dosage. Therefore, it was possible to verify the expressive potential (economic and environmental) of the use of RCD in the composition of cold asphalt concrete, as layers of asphalt, in low traffic pavements.

ABSTRACT In civil construction, a recurring environmental problem is the generation and disposal of Construction and Demolition Waste (RCD) of works. The use of RCD as aggregates of pre-mixed mixed asphalt concrete (PMF) makes possible the implementation of low traffic pavements. Therefore, this article proposes to evaluate the technical feasibility of the recycled materials, through laboratory tests and dosages of asphalt concrete, replacing natural aggregates by recycled in mixtures of asphalt concrete to be used as floor covering layer. In the research, analyzes of physical characterization of the material were carried out; mineralogical characterization of the RCD filler (DRX, FRX, EDS and MEV); and analyzes of Marshall's dosages of asphalt concrete (Pre-mixed to PMF) varying in asphalt emulsion contents in 6%, 7%, 8% and 9%, in each mixing design. The FRX results indicated oxides such as SiO2, Fe2O3 and Al2O3, with significant silica, iron and aluminum contents, also characterizing the predominantly ceramic origin of the RCD material. Analyzing Marshall methodology parameters, the interaction of emulsion contents with Stability, Void Volume, Density, and Empty Bitumen properties showed lower performance of concrete with RCD aggregates, however, consistent with the Marshall standard parameters of dosage. Therefore, it was possible to verify the expressive potential (economic and environmental) of the use of RCD in the composition of cold asphalt concrete, as layers of asphalt, in low traffic pavements.