Studies on Effect of Sulphuric Acid Attack on Concrete Made with Colloidal Silica as Replacement and Addition to Cement

Abstract

Rapid face of urbanization has lead to increase in concrete production, rising concerns about its implications for climate change, depletion of resource materials and environmental degradation. Concrete is prone to attacks by various aggressive environment effects. Depending upon the requirements, different types of concrete have been developed using nano based materials. One of the most used materials at nano scale is nano silica. The effect of use of nano silica in the form of colloidal silica is used in the present study as replacement and addition to cement to study the sulphuric acid attack on concrete. Colloidal silica with 30% of nano solids of SYCOL-TX is replaced and added to cement in different proportions i.e., 0, 0.5, 1, 1.5, 2, 2.5 and 3% respectively. Optimum mix is found out by conducting compressive strength test to concrete specimens after 28 days of curing. The test samples prepared with optimum content of colloidal silica are immersed in different concentrations of 1.5, 3, 4.5 and 6% sul - phuric acid solution for a time period of 28, 56, 90 and 180 days, after 28 days of water curing. Visual appearance, weight loss and compressive strength lossare determined in the study to study the effect of sulphuric acid attackon concrete specimens. From the results it is observed that incorporation of colloidal silica in concrete enhances its compressive strength and resistance to acidic environments in terms of durability.