The Effect of Fly Ash Composition and Drying Time Concrete Brick in Density Test

Institut Teknologi Padang, Mechanical Engineering Department, Padang, West Sumatra, Indonesia

Abstract

This study uses the fly ash (FA) from coal combustion power plant Sijantang Sawahlunto. By utilizing fly ash in concrete brick can reduce the negative impact on the environment, composition of fly ash in concrete brick at 0, 5, 10, and 15 wt.% FA concrete brick added material (sand, cement and water as a binder). Influence of drying time 7, 14, 21, 28, and 35 days. Test specimen based on SNI 03-0349-1989, with size of 34 x 12 x 9 cm. The results showed that the composition of 5 wt.% fly ash with 28 days drying time was found to be the highest density with 2,230 gr/cm³, while the lowest density in the composition test was 15 wt.% fly ash with 35 days drying time with the density 1,946 gr/cm³. In this study, the density of normal concrete brick density with density 2,208-2,230 gr/cm³ and light concrete brick density of 2,000-1,946 gr/cm³, and also found a normal and light concrete brick category that is 2,022-2,053 gr/cm³.