KUAT TEKAN BETON BERDASARKAN VARIASI UKURAN AGREGAT KASAR DENGAN MENGGUNAKAN BAHAN TAMBAH PLASTICIZER

Abstract

“Every aspect of development cannot be separated from concrete materials, such as the construction of roads, buildings, bridges, and other infrastructure”. The quality of good concrete is greatly influenced by the gradation and size of coarse aggregate and the use of the water-cement factor. The cement water factor is closely related to compressive strength and workability. The use of a high cement water factor in concrete can increase workability with ease, but it will cause the obtained compressive strength to be low. A concrete mix with a low water-cement factor can obtain a high compressive strength value, but the consistency of the slump value becomes low, making it very difficult to carry out concrete work. To maintain the quality of concrete with good compressive strength values, plasticizer additives can be used. The purpose of this study was to analyze the compressive strength of concrete based on variations in coarse aggregate using plasticizer additives of 0 cc, 80 cc, 120 cc, 200 cc, and 250 cc with treatment of specimens for 7 days, 14 days, and 28 days. The design of the concrete mixture in this study used the method in "SNI 7656:2012," which is a reference to "ACI 211.1-91." The compressive test object used is a cylinder with a diameter of 15 cm and a height of 30 cm.

Based on the research results, the highest average compressive strength of concrete at the age of 7 days was 42.70 MPa with the addition of 80 cc of plasticizer. At the age of 14 days, the average compressive strength of concrete was 44.46 MPa with the addition of 120 cc of plasticizer. “For the highest compressive strength at 28 days, the compressive strength of concrete was obtained” at 45.84 MPa with the addition of 120 cc of plasticizer. From the research carried out, it proves that plasticizers are very useful in increasing workability without reducing the quality of concrete, but only by using the right pliers.