All hydraulic cementing materials made of portland cement clinker, 0-5% limestone or granulated blast furnace slag and appropriate amount of gypsum are called portland cement. Portland cement can be divided into two types, one is Grade I Portland cement without admixture, the other is Grade II Portland cement with limestone or granulated blast furnace slag mixture not exceeding 5% of the cement mass when grinding Portland cement, and the other is Grade II Portland cement with code name P.II ..

Portland cement

All hydraulic cementing materials made of portland cement clinker, 6- 15% mixed materials and appropriate amount of gypsum are called ordinary portland cement, and the code name is p.o. When the active mixed materials are mixed, the maximum mixing amount is not more than 15%, in which it is allowed to mix pit ash not more than 5% or cement not more than 10%. When mixing inactive mixed materials, the maximum dosage shall not exceed 10% of the cement quality. The strength grade of portland cement is 42.542.5r52.5r62.5r, and that of ordinary cement is 32.532.5r42.5r42.5r52.5r The cement can be bagged or bulk, and the net content of each bag of cement is 50. The total mass of 20 bags randomly selected should not be less than1000. Other packaging forms shall be determined by the supplier and the buyer through consultation, but the requirements for the quality of packaging bags must conform to the above principles. Cement packaging should comply with the provisions of GB9774.

Cement bags shall be clearly marked with: product name, code number, net content, strength grade, production license number, manufacturer's name and address, factory number, implementation standard number and packaging year, month and year. Ordinary cement mixed with volcanic ash mixture should also be marked? Mixed with volcanic ash? Words. The name and strength grade of cement should be printed on both sides of the packaging bag. Portland cement and ordinary cement should be printed in red. During transportation and storage, cement shall not be affected with damp and mixed with impurities. Cement with different varieties and strength grades shall be stored and transported separately, and shall not be mixed.

Slag portland cement

All hydraulic cementing materials made of portland cement clinker, granulated blast furnace slag and appropriate amount of gypsum are called slag portland cement, and the code name is P.S. The mass content of granulated blast furnace slag in cement is 20-70%, and it is allowed to replace slag with a mixture of limestone, cellar ash, fly ash and volcanic ash, and the substitution amount shall not exceed 8% of the cement mass, and the granulated blast furnace slag in the cement after substitution shall not be less than 20%.

Volcanic pozzolanic silicate cement

All hydraulic cementing materials made of portland cement clinker, pozzolan mixture and appropriate amount of gypsum are called pozzolan portland cement, which is called pozzolan cement for short, and the code name is P.P. The mass content of pozzolan mixture in cement is 20-50%.

Fly ash portland cement

All hydraulic cementing materials made of portland cement clinker, fly ash and appropriate amount of gypsum are called fly ash portland cement (fly ash cement) code P.F. The content of fly ash in cement is 20-40% by mass. Strength grade: slag, volcanic ash, fly ash cement strength: 32.532.5r42.5r52.5r Green for slag cement bag printing. Volcanic ash and fly ash are black.

Composite portland cement

All hydraulic cementing materials made of portland cement clinker, two or more specified mixed materials and appropriate amount of gypsum are called composite portland cement (hereinafter referred to as composite cement). The total content of the mixture in the cement slurry should be greater than 15% (by mass), but not greater than 50%. It is allowed to use no more than 80% pit ash to replace part of the admixture in cement, and the content of admixture should not be repeated with slag portland cement when slag is mixed. Strength grade: 32.5 32.5r42.5r42.5r52.5r Name and strength grade should be printed in black on both sides of the packaging bag.