Rapid Hardening Cement Products
Rapid hardening cements differ from ordinary cement product types in many respects. One is that the ratio of limestone to silicates and tri-calcium silicate a rapid hardening cement product is higher than in other ordinary cement products. This type of cement is characterized by being smoother than other ordinary cement products, which leads to rapid hardening and rapid temperature generation. Rapid hardening cement is also used in the construction of roads.
Low Heat Portland Cement
This type contains a low percentage of the Tri-calcium sulfate and tri-calcium aluminate, leading to the low temperature generated. Ferric oxides are used to reduce the ratio of tri-calcium aluminate and thus, the ratio of tetra-calcium aluminoferrite is increased in this type of cement product.
Sulfate Resisting Cement
This Portland cement is a resistant chemical effects and attacks, in particular, sulfate.
It is called Sulfate Resisting Cement to distinguish it from other types of Portland cements.
It has a low ratio of Tri-calcium aluminate and is characterized by a high level of resistance to sulfate substances. This could be attributed to the components of this cement or to the processes followed in its production.
Thus, it is used in conditions where high resistance to sulfates is required. Also, it is worth noting that the higher the alumina in Portland cement, the higher the danger of the effects of sulfate-based solvents on Portland cement.
Thus, it is inescapable not to substitute alumina with iron to produce the type of sulfate resisting cement.
Experiments have shown that the adding a small quantity of barium carbonate to the rawmix would make the cement resistant to sulfate ( (because barium carbonate reacts with sulfur water to produce insoluble barium sulfate).
Portland Pozzolana Cement
It is produced by adding Pozzolana to the ordinary Portland cement clinker. Portland Pozzolana cement is featured by having different specifications and ingredients from other types of Portland cements.
It is composed of (70% -80%) of Portland cement, added to that a ratio of (15-20%) of Pozzolana. ( Pozzolana is a naturally siliceous, aluminous and volcanic material extracted directly from volcanic mountains.
It is not subject to any reactions neither does it need any chemical additives. Therefore, it is recommended to use it as the different uses of this material brings no no damages or negative effects.