Portlandsement

Portlandsement is a term used in some languages to refer to Portland cement, the widely used hydraulic binder in construction, or to cementitious blends that incorporate Portland cement with supplementary cementitious materials. In trade and technical literature the word may appear as an umbrella designation for standard Portland cement as well as for blended cements whose clinker content is reduced to improve durability or lower carbon emissions. Portland cement itself was developed in the early 19th century, with the first patent by Joseph Aspdin in 1824; the name derives from a resemblance to Portland stone quarried in England.

In typical practice, Portlandsement consists primarily of calcium silicate hydrates formed during the hydration of Portland cement clinker, with gypsum controlling the setting time. When blended with supplementary cementitious materials such as fly ash, slag, or natural pozzolans, the resulting Portlandsement exhibits enhanced longevity, reduced heat of hydration, and lower clinker content. Admixtures may further tailor workability, set time, and durability.

Applications include general concrete production for buildings, infrastructure, and precast elements. Variants include Portland cement blends and Portland-limestone cement, the latter incorporating limestone to reduce cement clinker demand.

Environmental considerations center on reducing CO2 emissions from clinker production. Blended Portlandsement formulations aim to cut clinker content and energy use while preserving strength and durability.

See also Portland cement, concrete, cementitious materials, concrete admixtures.