Durability in cement and concrete refers to the ability of these materials to withstand the physical and chemical processes that cause deterioration over time. This encompasses resistance to mechanical stress, chemical attack, weathering, and other environmental factors. The durability of concrete is primarily determined by its pore structure and the quality of the cement paste, which binds the aggregates together. Well-hydrated cement creates a dense matrix that impedes the ingress of harmful agents such as water, chlorides, sulfates, and gases, which can cause corrosion, freeze-thaw damage, and chemical degradation.