INVESTIGATION ON MECHANICAL PROPERTIES OF SILICA AND GGBS INCORPORATED CEMENT MORTAR

Maitri Mapa, Hemalatha, T., Rama Chandra Murthy A

Abstract: The usage of mineral admixture in concrete is mounting with regards to socio-economic understanding, energy conservation, and environmental preservation, as well as for better engineering and performance of concrete. However, more usage of supplementary cementitious material in concrete is restricted due to lack of gain in strength at early ages. In this study, an attempt has been made to investigate the effect of partial replacement of cement with various percentages of GGBS on mechanical properties. Cement was replaced with GGBS in the proportions of 20%, 40%, 60%, 80% respectively and compressive strength test has been conducted at mortar level from 1st to 90th day under normal water curing. It has been observed that, the compressive strength of mortar is decreasing at all days, generally, and at early ages, particularly with the increasing replacement of GGBS. To compensate the loss in strength, silica rich admixtures, such as densified silica fume, nano silica and micro silica have been blended with the GGBS in cement during mortar mix preparation. The compressive strength of silica blended mortar mixes has shown good enhancement at early ages, compared to the GGBS-cement mix. Among all siliceous compounds, addition of 1% nano and 5% mico silica show better improvement at early age compressive strength.

Keywords: GGBS, nano silica, mechanical properties

DOI: https://doi.org/10.15623/ijret.2015.0425005