Experimental Study on Light Weight Concrete Bricks by Partial Replacement of Fine Aggregate with Styrofoam

Abstract

This study investigated into the effect of Styrofoam used as partial replacement for fine aggregate on properties of concrete bricks such as absorption, density and compressive strength. Furthermore, the optimum Styrofoam content in concrete bricks which meet minimum values specified by local codes was recommended afterwards. Styrofoam content at 0.2%, 0.4%, 0.6%, 0.8%, 1% and 2% were used in this research. Other constituents of the concrete bricks include: water, cement, sand and Bida Natural Gravel (BNG) in the ratio: 0.5:1:4:2 respectively. Absorption of concrete bricks were taking after 24 hours, 7 days and 28 days. Absorption increased with increasing Styrofoam content but decreased with increasing curing days. For density, there was a significant decrease in weight as the Styrofoam increased in the concrete bricks. Also, compressive strength was inversely proportional to Styrofoam content. At 28 days, absorption of concrete bricks was 2.5%, 5.6% and 8.5% for 0%, 0.2% and 0.4% Styrofoam content respectively. For compressive strength at 7 days, the values were 6.7, 2.9 and 2.0 N/mm2 at 0%, 0.2% and 0.4% Styrofoam content respectively. Furthermore, at 28 days, compressive strength improved to 9.9, 3.8 and 2.1 N/mm2 at 0%, 0.2% and 0.4% Styrofoam content respectively. In conclusion, this research recommended Styrofoam content ranging from 0.2% to 0.4% for use in concrete bricks production as the values for absorption and compressive strength were within minimum requirement as specified by local codes.