Portland Slag Cement - IS 455
Portland slag cement shall be made by mixing Portland cement clinker, gypsum, and granulated slag in the appropriate quantities and grinding the mixture to get a thorough and intimate mixing of the constituents. It can also be made by grinding Portland cement clinker, gypsum, and granulated slag separately and then mixing them thoroughly. The resultant product is Cement with physical qualities similar to standard Portland cement. The slag constituent of the Portland slag cement must be not less than 25% and no more than 65 percent.