Estudo da eco-eficiência de argamassas e concretos reciclados com resíduos de estações de tratamento de água e de construções e demolições.
Abstract
Traditional and recycled mortar and concrete have been produced and the results from simple
compression strength and water absorption tests have been compared. Recycled mortar and
concrete have been produced out of sludge from water treatment plants and rubble from
construction and demolition. The amount of aluminum present in the leached extract from the
solubilization process of the concrete produced with the addition of both sludge from water
treatment plants and rubble from construction and demolition has been determined. In terms
of simple compression strength, the addition of up to 4 % of sludge in mass in place of natural
sand has made it possible to obtain recycled concrete with similar characteristics to traditional
concrete. Although water absorption of concrete and mortar produced from both sludge from
water treatment plants and rubble from construction and demolition is much higher than water
absorption of traditional mortar and concrete, the results have not made it impossible to use
them; it has just restricted their application to places free from moist resulting from weather
conditions or use characteristics. The leached extract resulting from the solubilization of the
concrete produced out of both sludge from water treatment plants and rubble from
construction and demolition has shown aluminum concentration higher than the drinkability
standard defined by the Brazilian standards agency (ABNT), but not in such a level to turn the
rubble from the recycled product dangerous to human health.