Comparative Study on Strength of Foamed Concrete Consisting Hybrid Fiber

Abstract

This paper presents the performance of foamed concrete (FC) with two additives, namely coir fiber (CF) and steel fibers (SF), which can be categorized as hybrid fiber materials that are environmentally friendly because one of the fibers is an agricultural waste. In addition, it can also increase the foamed concrete strength. The CF was added in the FC mixture in three different percentages; namely 0.5%, 1% and 1.5% with fixed SF percentage at 3% for each mixture. The FC-CF-SF mixtures were tested in the laboratory to determine its fresh properties and mechanical properties. From the findings it showed that the workability of foamed concrete reduced when the hybrid fiber increased. The result presents the highest value of compressive strength was 21.9MPa obtained on FC-CF-SF with percentage of 1% CF and 3% SF at 28 days. For tensile strength, the highest value obtained from the test on cylinder specimen at 28 days was 1.94MPa with FC-CF-SF added with 0.5% CF and 3% SF. Meanwhile, the maximum value of flexural strength achieved was 3.4MPa obtained on FC-CF-SF added with 1% of CF and 3% of SF and the highest ultimate load recorded was 8.27MPa obtained on FC-CF-SF added with 1% of CF and 3% of SF content. Based on the observation, the foamed concrete consisting hybrid fiber experienced less crack compared to control specimen.