Some durability characteristics of micro silica and nano silica contained concrete

Abstract EN

This paper aims to investigate the influence of replacement of cement with nano and micro silica admixtures on some durability properties of concrete such as water absorption, chloride content and pH tests.

Three replacement ratios (5%,10%,15%) of micro silica and four replacement proportions (0.5%,1.5%,3%,5%) for nano silica were used in this study.

Two exposure conditions were considered for chloride content test: wetting-drying and full immersing exposure in 6% of chloride ions solution, NaCl type.Results showed that mixes of %5 micro silica and 5% nano silica had lower content of chloride (about 0.19% and 0.18%) for wetting-drying and full immersing exposure respectively.

For water absorption test, all mixes incorporated micro and nano silica, except for %5 micro silica mix, showed lower absorption than control mixes.

For pH test, results indicated that the adding of nano and micro silica didn’t affect adversely the alkalinity of concrete