Influence of nanosilica on mechanical and durability properties of concrete

Abstract

The results of an experimental study on the effect of the partial replacement of ordinary Portland cement with nanosilica (NS) on the mechanical and durability properties of concrete are presented. Concrete mixes were made with varying NS contents at a constant water/binder ratio of 0·40. The test results demonstrated that the inclusion of 3% NS as a partial replacement of cement enhanced the mechanical properties and reduced the water penetration depth and water absorption of the concrete, resulting in overall improved performance. Compared with normal concrete, the water penetration depth and water absorption of the NS concrete was reduced by 42·85% and 36·84%, respectively. The carbonation depth was also reduced as a result of cement replacement with NS, leading to enhanced concrete durability. These enhancements in the mechanical and durability properties were mainly due to the high fineness and increased pozzolanic activity of the added NS.