cimento

Cimento, commonly referred to as cement in Portuguese and Italian, is a binding powder used in construction. When mixed with water, it hydrates and forms a paste that hardens, binding sand, gravel, or other aggregates into concrete or mortar.

The most widely used form is Portland cement, produced by calcining a blend of calcium carbonate (limestone) and clay or shale to form clinker, which is ground to a fine powder and mixed with a small amount of gypsum to control setting.

Cement consists mainly of calcium silicates, aluminates, and aluminoferrites. Hydration with water generates heat and strength over time. The modern Portland cement, developed in the 19th century, replaced older lime-based cements, and today many blends with supplementary cementitious materials are used.

Applications include concrete, mortar, and grouts for buildings, roads, dams, and other infrastructure. Portland cement gains most strength within days to weeks, with curing conditions such as moisture and temperature influencing final performance.

Production is energy-intensive and a major source of industrial CO2. Efforts to reduce environmental impact include blended cements with fly ash, slag, or silica fume, use of alternative clinkers, and carbon capture technologies, all within standards set by bodies such as ISO, EN, and ASTM.

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