PENGARUH PENGGANTIAN SEBAGIAN SEMEN DENGAN FLY ASH TERHADAP KUAT TEKAN MORTAR PADA UMUR 14, 28, DAN 56 HARI

Coal is one of the main sources of procurement of cheap and efficient national electrical energy sources, but has several shortcomings, one of which is being a source of pollution and is a hazardous waste for the environment, flying ash or commonly called fly ash is solid waste produced from combustion coal in power plants. Prior to coal combustion in power plants, fly ash obtained from coal combustion production was then processed simply by using a gas funnel and spread into the air. In this study, efforts to use fly ash as a partial cement replacement were carried out. The beginning of this research was carried out with data from material testing followed by snaking mix design calculations, the results of the mix design will be used for the manufacture of test objects. The test objects made for each variation were 3 test objects. Each variation of 0, 5, 15, and 25% of cement. The specimens were treated for 14, 28, and 56 days. The test was carried out using the Universal Testing Machine (UTM). The test results showed that the optimum compressive strength of the addition of some fly ash occurred at 25% fly ash content with 56 days of age. the variation of the test age showed that 56 days of age is the age where the highest compressive strength is produced, so fly ash can still increase in the binding process after the age of the specimen is 28 days.