STUDI EKSPERIMENTAL KINERJA CAMPURAN BETON MUTU 25 MPA MENGGUNAKAN MATERIAL FLY ASH DAN LIMBAH KERAMIK SEBAGAI BAHAN SUBSTITUSI

Abstract

Concrete is a widely used construction material, creating a need for the utilization of alternative materials and waste as partial substitutes in concrete mixtures. This study aims to investigate the effect of ceramic waste as a fine aggregate substitute, with 25% fly ash as a partial cement substitute, on the workability, water absorption, and compressive strength of 25 MPa concrete.

This study employed an experimental method conducted at the Materials Testing Laboratory, Department of Civil Engineering, Manado State Polytechnic. The test specimens were cylindrical concrete specimens measuring 10 × 20 cm, with ceramic waste substitution variations of 0%, 5%, 7.5%, 10%, and 12.5%, while fly ash was used at a constant 25% in all mixtures. The tests included slump, water absorption, and compressive strength at the ages of 7, 14, and 28 days.

The results showed that the slump value decreased from 6.0 cm for the normal concrete mixture to 3.5 cm for the 12.5% ceramic waste variation. At 28 days, the lowest water absorption value was obtained from the 10% ceramic waste variation, at 2%. The compressive strength of normal concrete was 26.21 MPa, while the compressive strengths of the 5%, 7.5%, 10%, and 12.5% ceramic waste variations were 21.34 MPa, 19.80 MPa, 17.94 MPa, and 17.23 MPa, respectively. Therefore, increasing the proportion of ceramic waste tended to decrease the workability and compressive strength of the concrete, while the lowest water absorption was obtained at a ceramic waste substitution level of 10%.