| dc.description.abstract | Analysis of LOI, IR, SO3 and Compressive Strength Portland Cement has been carried out on variations in the addition of limestone at PT Cemindo Gemilang Medan. The purpose of this research is to determine the variations in the addition of limestone to the compressive strength. The manufacture of composite portland cement was carried out by adding limestone at variations of 15%, 20%, 25% for compressive strength. Each sample was tested for LOI, IR, SO3 and Compressive Strength. The LOI test used by the glowing method, the IR test used the digest method (separation), the SO3 test used the precipitation method, the compressive strength test used the physical method. Based on the results of the analysis obtained, the LOI content in the addition of limestone is 15%, 20%, 25%, equal to 8,2500%, 10,0200%, 11,0700%. The IR content in the addition of limestone 15%, 20%, 25%, equal to 17,6100%, 13,5400%, 8,9900%. The SO3 content in the addition of limestone 15%,
20%, 25%, equal to 1,8200%, 1,0838%, 1,7767%. Compressive strength test with the addition of 15% variation limestone , on day 3,7,28 days of 179,8071 kg/cm2, 224,0076 kg/cm2, 336,9904 kg/cm2. The addition of limestone at 20% variation, on day 3, 7, 28 days of 181,9280 kg/cm2, 226,1966 kg/cm2, 345,8414 kg/cm2. The
addition of limestone at 25% variation on day 3, 7, 28 days of 192,1114 kg/cm2, 236,5024 kg/cm2, 358,5401 kg/cm2 . Based on the data obtained, it can be concluded that the higher the concentration of limestone added and the better the storage time at 3, 7, 28 days, the compressive strength increased. | en_US |
