PENGARUH KARANG JAHE SEBAGAI SUBSTITUSI AGREGAT HALUS TERHADAP KUAT BELAH DAN LENTUR BETON SELF COMPACTING CONCRETE

Abstract

Modern concrete innovations must meet the demands of high quality, work efficiency, and environmental sustainability. One such innovation is Self Compacting Concrete (SCC), an innovative concrete that can compact independently without mechanical compaction. This study examines the use of ginger coral as a substitute for fine aggregates in SCC concrete. Ginger coral is a natural material that thrives in coastal areas but is rarely used in construction. The use of this material is expected to improve the performance of concrete while supporting environmental conservation and the use of local resources. Substitution is carried out in three variations: 0%, 10%, and 15% of the total volume of fine aggregates. The tests include tensile strength on cylindrical test pieces aged 7, 14, and 28 days, as well as flexural strength on 28-day-old beam test pieces. A total of 12 samples were used: 9 cylinders (3 each for each variation) and 3 beams (1 each for each variation). The results showed that the substitution of 15% ginger corals yielded the highest tensile strength at 28 days of age of 9.30 MPa for cylinders, and flexural strength of 4.13 MPa for beams. These findings prove that ginger coral as a partial replacement for fine aggregates in SCC is able to provide good mechanical performance, particularly in tensile and bending strength. In addition, the use of ginger coral can be an alternative solution to reduce dependence on natural sand, supporting sustainable development in the construction sector.