Cement is a common and commonly used raw material in our daily life, such as building roads, building houses, etc. At present, the commonly used slag Portland cement and ordinary Portland cement, although both are cement, However, they are different in application and component.

The raw materials of ordinary Portland cement are mainly silicate, gypsum and some mixed materials.

In addition to gypsum and silicate, Portland slag cement also has some mineral materials such as granulated blast furnace slag.

(The slag powder added to Portland slag cement is the fine powder obtained after blast furnace slag is processed and ground by a vertical slag mill. The specific surface area of the finished product can reach the range of 400~550㎡/kg, and the activity is good.)

Advantages and disadvantages of slag Portland cement and ordinary Portland cement

Ordinary Portland cement has the advantages of high early strength, earlier setting time than slag Portland cement, better atmospheric resistance and frost resistance than slag cement, and less bleeding, so it is better to use in winter than slag cement. Due to its fast setting time and good early strength, it is suitable for high-rise buildings, large-volume concrete projects, and important projects.

Disadvantages of ordinary Portland cement: It has some excellent performance and energy-saving characteristics, but there are some shortcomings that are difficult to overcome, such as alkali-aggregate reaction problems, large dry shrinkage problems, and easy moisture absorption of the cement itself. During construction Due to the high viscosity of mortar and concrete, the problem of difficult operation, the problem of corrosion to human body and equipment, and the problem of the source of raw materials (industrial waste residue), it is impossible to widely promote production and use.

Advantages of Portland slag cement: stable setting time, initial setting is generally 2.5 to 4 hours; final setting is generally 4.5 to 6.5 hours, stable strength, low heat of hydration, water resistance and carbonate resistance performance and Portland cement Similar, the stability in fresh water and sulfate cement is better than Portland cement, the heat resistance is better, and the bonding force with steel bars is also very good.

Disadvantages of slag Portland cement: Atmospheric resistance and frost resistance are not as good as Portland cement; it has poor workability and large bleeding, so it is not suitable for outdoor construction in winter. Therefore, corresponding measures should be taken during construction, such as strengthening Moisture protection and maintenance, strictly control the amount of water added, use heat preservation and maintenance during low-temperature construction, and some additives can also be added.