AASHTO M85:2016 Standard Specification for Portland Cement.
5.1.3. Limestone—The amount shall be not more than 5.0 percent by mass such that the chemical and physical requirements of this standard arc met (see Note 3). The limestone, defined in ASTM C5 1, shall be naturally occurring and consist of at least 70 percent by mass of one or more of the mineral forms of calcium carbonate. If limestone is used, the manufacturer shall report the amount used, expressed as a percentage of cement mass, as determined using Annex B, along with the oxide composition of the limestone.
Note 3—The standard permits up to 5 percent by mass of the final cement product to be naturally occurring, finely ground limestone, but does not require that limestone be added to the cement. Cement without ground limestone can be specified in the contract or order.
5.1.4. Inorganic Processing Additions—The amount shall not be more than 5.0 percent by mass of’ cement. Not more than one inorganic processing addition shall be used at a time. For amounts greater than 1 .0 percent, they shall have been shown to meet the requirements of M 327 for inorganic processing additions in the amount used or greater. If an inorganic processing addition is used, the manufacturer shall report the amount used, expressed as a percentage of cement mass, along with the oxide composition of the processing addition (see Note 4).
Note 4 These requirements are based on data and recommendations by Taylor.
5.1.5. Organic Processing Additions—These additions shall have been shown to meet the requirements of M 327 in the amounts used or greater, and the total amount of organic processing additions used shall not exceed 1.0 percent of the weight of portland cement clinker.
5.1 .6. Air-Entraining Addition (for Air-Entraining Portland Cement Only,—The interground addition shall conform to the requirements of ASTM C226.
6. CHEMICAL COMPOSITION
6.1. Portland cement of each of the ten types shown in Section 1 shall conform to the respective standard chemical requirements prescribed in Table 1. In addition, optional chemical requirements are shown in Table 2.
Note 5—The limit on the sum, C3S + 4.75C3A, in Table I provides control on the heat of hydration of the cement and is consistent with an ASTM C186 7-day heat of hydration limit of 335 kJ/kg (80 cal/g) or an ASTM C 1702 3-day heat of hydration limit of3l5 kJ/kg (75 cal/g). Note 6 —There are cases where performance of a cement is improved with SO3 in excess of the Table 1 limits in this specification. ASTM C563 is one of several methods a manufacturer can use to evaluate the effect of sulfate content on cement characteristics. Whenever SO3 content of a cement exceeds Table 1 limits, ASTM C1038/C1038M results provide evidence that excessive expansion does not occur at this higher sulfate content.AASHTO M85 pdf download.