STUDY OF THE EFFECT OF NANO SILICA ON THE SELF HEALING ABILITY OF HIGH STRENGTH CONCRETE WITH CRYSTALLINE ADMIXTURE

The aim of this study is analyzing the self-healing capability of high strength concrete (M70) with nano silica and crystalline admixture in three types of environmental exposures i.e. water immersion, wet/dry cycles and water contact. The percentage replacements of cement with nano silica were 1%, 2%, 3% with addition of 1.1% crystalline admixture. The specimens were pre-cracked at 28 days in the range of 0.10-0.40mm and the time set for healing was 42 days. The result shows that all the mixes have considerable amount of closing ability and strength regaining capacity for all exposure conditions. The concrete with 2% nano silica and 1.1% crystalline admixture (CA) has complete crack closing ability and strength regaining capacity for water immersion and wet/dry cycle conditions