Study on the Freeze-Thaw Performance of Concrete Using Granulated Blast-Furnace Slag as Fine Aggregate

Abstract

In this paper, the freeze-thaw performance of concrete using granulated blast-furnace slag (GBS) as fine aggregate was studied. According to the test method for slow freezing and thawing, degradation of mechanical properties about GBS concrete with 2 kinds W/B ratio and 3 kinds GBS replacement ratio were tested, and micromorphology of GBS concrete were analyzed by scanning electron microscopy (SEM). Furthermore, relations between degradation of mechanical properties and micromorphology about GBS concrete are discussed. Test results show that: after freeze-thaw cycles, the relative compressive strength of GBS concrete is greater than ordinary river sand concrete, and the GBS concrete will produce more mutual interlacing fibrous and flowers from crystal, the growth of these crystals can improve the compressive strength of concrete. Therefore, the frost resistance of GBS concrete is little better than ordinary river sand concrete.

Keywords

• granulated blast-furnace slag
• concrete
• freeze-thaw
• SEM