O uso do resíduo pedra Cariri como material alternativo para aplicação em camadas granulares de pavimentos

Abstract

The growing preoccupation with the environment and the self-sustainability have encouraged many researches in the paving area for adding residues in its different layers. The final disposition of the residues, with no proper management, causes the pollution of air, soil and hydro resources, which may result in damage to human beings and environment. The law 12.305/2010 instituted the National Policy of Solid Waste in Brazil and it shows the concern with the issue. In Metropolitan Region of Cariri (MRC), located to the south of Ceará, Brazil, there is a mineral pole in the cities of Nova Olinda and Santana do Cariri that commercializes an ornamental rock whose name is Cariri Stone. The Cariri Stone Residue (CSR) was studied at the present research due to the potentiality of its use in paving and to its considerable accumulated quantity, over 1 million m³. Cariri Stone is a laminated calcareous in yellowish or bluish color. It is used for civil construction as floor and coating for walls. The objective of this research was to investigate the technical and costing viability of applying the CSR as alternative material in granular layers of pavements. So, the research was divided in four stages. On the first stage, it was investigated the granulometric stabilization of two soils from MRC with the CSR, it was verified that these mixtures can be used for pavement sub-base layers and that the pure CSR has high natural resistance. On the second stage, it was performed an evaluation of pure CSR and the CSR fitted in the A, B, C and D granulometric zones of DNIT, selecting the two best curves of CSR. The third stage was to make a chemical stabilization with cement of the two best mixtures, defined on the second stage, to verify the improvement in mechanical behavior of pure CSR. On the fourth stage, it was carried out the empirical and mechanistic-empirical dimensioning of pavements with CSR, as well as it was performed the technical and costing analysis. The presented experimental results showed that the Cariri Stone Residue is technically and economically viable to construction of pavement granular layers.