Utilização dos resíduos de cortes de placas de mármores e granitos como adição na fabricação de concreto autoadensável

Abstract

The aim of this study is to determine the possible replacement percentage of cement per waste marbles and granites (WMG) of marble shops of Manaus in the production of self-compacting concrete (SCC). The methodology adopted was to hold various laboratory tests: characterization of each constituent material of the CAA; the rheological properties of SCC; and mechanical, physical and chemical properties in the hardened state of SCC. Two superplasticizers have been applied, one on the base and other salts of sulphonated polymer based whose optimum content was determined by testing the slurry Marsh cone. The coarse aggregates and kids were characterized by assays granulometry, specific weight; unit mass in loose state; and unitary mass compressed and dry. The WMG were subjected to density testing and analysis of Fluorescence X Ray. For fresh SCC in the following tests were performed: scattering, scattering T500, V funnel and L box; and Testing of Compressive Strength and flexion, absorption, voids index and the SCC Density in the hardened state, as well as tests on mortar bars to check possible Alkali Aggregate Reaction (AAR). The results were effective for most traits SCC, up to 30% of the cement replacement by WMG when the additive polymer base was used, and up to 20% replacement when the superplasticizer was sulfonated. Fresh in this SCC met the requirements of ISO 15823, behaving like proper concrete for use in most current applications. In the hardened state near showed compressive strength of 35 MPa, may also be used in the production of concrete floors. The resistance to bending achieved in around 7.0 MPa and satisfy the Brazilian standard 15805. For absorption values were comprised between 4.0% and 5.0%, lower than the values found in the literature, for voids and density values were close to other research, 10%. In AAR tests achieved the expansion was less than 0.10%, and the waste classified as harmless by Brazilian standard 15577-4. With the above it can be said that the residues from marble shops may have an alternative destination in civil construction.