concretas

Concretas is the plural form used in some Romance languages to refer to concrete, a widely used construction material. Concrete is a composite that binds together cement, water, and aggregates (sand, gravel, or crushed stone) to form a rock-like mass as it hardens. Admixtures and supplementary cementitious materials may be added to modify properties such as workability, curing time, strength, or durability.

Typical concrete comprises cement as the binder, aggregates as the inert material, and water to drive the chemical reactions. Variants include reinforced concrete, which incorporates steel reinforcement bars to carry tensile forces; prestressed concrete, where tensioned tendons improve performance; high-performance concrete with enhanced strength and durability; and fiber-reinforced concrete, which includes short fibers to improve toughness. Lightweight and heavyweight concretes use different aggregates to alter density and insulation properties.

Key properties of concretas include high compressive strength but relatively lower tensile strength unless reinforced. Durability depends on proper mix design, curing, and exposure conditions. Permeability, shrinkage, and thermal properties influence performance in structures subjected to weather, chemicals, or freeze–thaw cycles.

Manufacturing and placement involve mixing, transporting, placing into formwork, compacting, and curing under controlled conditions. Concrete is used in a wide range of applications, including foundations, floors, walls, bridges, pavements, and precast elements.

Historically, Romans used early pozzolanic concretes, while modern Portland cement, developed in the 19th century, enabled modern construction. Today, sustainability concerns drive the use of supplementary cementitious materials, recycled aggregates, and alternative binders to reduce the environmental footprint of concretas.