Análise comparativa do desempenho de argamassas colantes utilizando areias do município de Porto Velho – Estado de Rondônia

Abstract

Dry-set mortars are widely used in civil construction, and are made basically of cement, sand, water and admixtures. However, their factories are located far from the city of Porto Velho, in the industrial nuclei of Brazil, most of them in São Paulo, which rises the final price of the product. This research aimed to develop a dry-set mortar using sands extracted in Porto Velho.Two types of quartz sands extracted from the river, Celotex K60® chemical admixture and CP IV-32 cement were used in the formulation of three distinct mix proportions of mortar. In order to characterize the sands, there were made tests measuring their density, unit mass, moisture and granular distribution. The mortarswere characterized by the tests of water retention rate, tensile bond strength, axial compressivestrength, diametralcompressive strength, and also by the evaluation of thecracking pattern of the specimens. The results have shown that both sands have similar physical and granulometric properties, in the other hand, it was possible to notice the relationship between the bulk density fresh and the water retention. It was also seen that as the sand was increased as the bond and compressive strength were decreased.It is concluded that the Sand A has a better performance than Sand B in terms of dry-set mortar composition,the mix proportion 1:3 (cement and sand) gives better results, however the mix proportion 1:4 has more suitable characteristics in terms of Brazilian standard for Industrial Mortars.