PERBANDINGAN MUTU BETON MENGGUNAKAN METODE UJI HAMMER TEST DENGAN UJI KUAT TEKAN PADA BETON CAMPURAN LIMBAH NIKEL (SLAG)

Indonesia is the largest nickel producer in the world, in 2022 Indonesia produced 1,600,000 metric tonnes of nickel. The processing of nickel ore which is used as a base material for stainless metals, industrial products, military, transportation, aviation, marine and architecture is by melting at high temperatures. This smelting process produces waste in the form of liquid slag which then undergoes cooling and changes shape into granules. Nickel waste (slag) is classified as toxic hazardous waste that is not environmentally friendly, therefore research was conducted to utilise slag as a substitute for fine aggregate in concrete which aims to be an effort to reduce environmental pollution and improve the quality of concrete. The purpose of this study was to determine the effect of using slag as a fine aggregate substitute on the compressive strength of concrete, and to determine the comparison of concrete quality in the two test equipment used. This test is a laboratory test with fine aggregate substitution with slag of 10%, 20%, and 30% for K-250 concrete quality and compressive strength testing using the Hammer Test and Compression Machine Test methods. The concrete mix is based on ASTM with the composition of cement, coarse aggregate, fine aggregate and water. The mix design is based on SNI 03-2843-2000 and concrete quality testing using hammer test based on SNI 03-4430-1997 and compressive strength testing based on SNI 03- 1974-1990. The test results using the Hammer Test method that the percentage increase in concrete with 10% slag variation is 3.88% with an average concrete quality of 264.78 kg/cm2, 20% slag variation is 12.96% with an average concrete quality of 287.95 kg/cm2, and 30% slag variation is 18.29% with an average concrete quality of 301.53 kg/cm2. While in the concrete compressive strength test at 10% slag variation did not experience an increase in compressive strength as planned, the average compressive strength was 205.41 kg/cm2. While the concrete variation with 20% slag mixture increased by 9,52% with an average compressive strength of 257.12 kg/cm2, and an increase of 14,29% in 30% slag variation concrete with an average compressive strength of 268.29 kg/cm2 when compared to normal concrete (without slag mixture) which has an average compressive strength of 238.95 kg/cm2.

Keywords: compressive strength, slag, K-250.