INFLUÊNCIA DA INCORPORAÇÃO DE VINHAÇA NAS PROPRIEDADES DE COMPÓSITOS CIMENTÍCIOS NO ESTADO FRESCO

Tension and compression stresses are introduced in the concrete when Portland Cement are used in large volumes, inducing pathologies such as micro-cracks related to sudden changes in temperature. Sucrose is used as a cement hydration retarding additive and produce good results. In this sense, vinasse is a source of sucrose still little explored. Vinasse is a by-product of the sugar and alcohol industry, produced in large volumes, making it very attractive in this application. This study investigates the influence of vinasse on hydration in cement pastes. The total reducing sugars (TRS) and total soluble sugars (AST) as well as the sucrose present in vinasse was determined through Fehling method. The amount of 25%, 50% and 100% of vinasse were used to substitute water in cement pastes composition. The consistency, initial and final setting time and thermal variation during hydration of pastes were. The results show that the lower amount of substitution (25%) leads to an increase in the initial and final setting time, while larger amounts did not cause the same benefits. The calorimetry test confirmed the results obtained by the setting time test, showing less heat of hydration of the paste with 25% substitution of water for vinasse.