4.9 : Types of Cement I

Portland cement comes in several types, each with distinct properties and applications based on their chemical composition and hydration characteristics:

Type I (Ordinary Portland Cement) is widely used for general construction where special properties are not required. It has moderate sulfate resistance and heat of hydration.

Type II (Modified Cement) offers moderate resistance to sulfate attack and a lower rate of heat development compared to Type I. It is suitable for structures in sulfate-bearing soils.

Type III (Rapid-hardening Cement) develops strength faster than Type I due to its higher fineness and tricalcium silicate content. This cement is ideal for quick construction and cold-weather applications. However, its high heat of hydration restricts its use in massive structures.

Type IV (Low-heat Cement) is used in massive concrete structures like dams, primarily because this cement produces less heat during hydration, reducing the risk of thermal cracking.

Type V (Sulfate-resisting Cement) is specifically designed to resist sulfate attack. It is suitable for environments with high sulfate exposure because it contains less tricalcium aluminate content in it, leading to reduced chemical reaction with sulfates.