Effect of Replacing Rice Husk Ash with Cement and Granulated Blast Furnace Slag with Fine Aggregates on High Performance Concrete

Abstract

Cement and sand are the basic materials for any concrete construction. Now a day’s due to erosion of rivers and considering environmental issues, there is a scarcity of river sand. Many researchers are finding different materials to replace sand and one of the major materials considered in this study is granulated blast furnace slag (GBFS). In recent times, instead of cement many alternative materials are being used as the binding material in the construction sector. One such binding material that can be used as a partial replacement for cement is rice husk ash (RHA). RHA is agricultural waste product obtained from paddy. The tests were carried out on the raw materials to check the suitability of the materials to be used for the research purpose and their properties were determined. M50 grade of concrete is adopted for this research. The cube specimens were cast with cement replaced by RHA varying from 0 to 20% at 10% interval and sand replaced by GBFS from 0 to 80% at 10% interval. The results show that the compressive strength of specimens with 10% of RHA yielded almost the same strength as of the specimens with 0% replacement. Replacement of sand with GBFS reduced workability, instead increased the compressive strength up to the replacement of 30%, with a percentage increase in strength of 12.15%. The overall results show that RHA and GBFS can be used in concrete with cement and sand being partially replaced. The percentage of replacement should be limited to 10% RHA and 60% GBFS. Keywords: Rice husk ash, granulated blast furnace slag, compressive strength.