Influência dos agregados graúdos na resistência à compressão do concreto quando submetido a temperaturas elevadas

Abstract

The present work aims to analyze the influence of coarse aggregates, according to their composition to their concrete composition, in high temperature parts. For a selection of hypotheses and development of conclusions, the concrete was made with aggregates of different degrees of origin, being used coarse aggregates of granite, basalt and limestone, due to their availability in the region, in which it was developed the research. The amount/cement of the concrete and the quantity of aggregates only varied the coarse aggregate utilized. After a period of 28 days, the molded specimens were subject at 4 different temperature ranges, 200C, 400°C, 600°C and 800°C, according to practices used in referential studies, for 60 minutes. The experiments determined: the residual compression resistance of the concrete, expansion rate and water absorption. Concrete using with basalt showed 6 percentage points higher than granite at 800°C. The limestone aggregate showed a resistance gain of 0.01% at a temperature of 200°C, while the others showed losses of 0.01% and 0.08% for basalt and granite, respectively. For basalt and granite respectively at their compressive strength.