Concrete in various forms can be dated back to 5600 BCE, where in Serbia the remains of a hut were found with a floor made of a mixture of red lime, sand, and gravel. In the Roman Empire, a concrete made from quicklime, pozzolanic ash/pozzolana, and an pumice aggregate was used. It was very similar to the modern portland cement concrete which was developed in the 1840’s and is currently in use today.
This topic includes information related to underwater concrete placed during construction. Underwater concrete is placed using a tremie, a vertical pipe with a funnel shaped top. Mixtures for underwater concrete are designed for a continuous pour and prevention of cement washout. Additives are used in conjunction with cement and aggregate to increase underwater concrete strength.
This topic includes information related to stamped concrete finishing of cast in place concrete during construction. Stamped concrete is achieved by applying an embossed skin, random interlocking or patterned mat to the surface of hardening concrete. The skin or mat imprints a desired pattern that resembles brick, slate, flagstone, cobblestone, tile and wood finished surfaces. Stamped concrete finishes are often blended with colored concrete finishing and exposed aggregate concrete finishing.
This topic includes information related to exposed aggregate concrete finishing of cast in place concrete during construction. Exposed aggregate concrete finishing is achieved by adding aggregates to concrete batch mix, the surface of the cast in place concrete is removed and in some cases the concrete surface is polished.
This topic includes information related to architectural concrete that is cast in place during construction. Architectural concrete, which is composed of a mixture of cement, aggregate, water and admixtures, is an exposed concrete that has an aesthetically pleasing, finished appearance. Architectural concrete appearance is achieved with special forms, finishing methods and special, mixture, components. Various types of architectural concrete include; heavyweight and lightweight.
This topic includes information related to structural concrete that is cast in place during construction. Structural concrete, which is composed of a mixture of cement, aggregate, water and admixtures, has a dull, gray color with a rough texture. It is commonly concealed behind interior finishes. Structural concrete is reinforced with steel and can be cast in place as a beam, column, girder, joist, slab or other structural member. Various types of structural concrete include; heavyweight, lightweight, shrinkage compensating, high performance and self compacting.
One of the most important advantages of concrete is its workable, viscous state that allows it to be formed into literally any solid shape. Concrete Forming refers to the temporary or permanent support structures used to contain concrete as it is poured and while it hardens. Formwork can be made of many different materials, and it can be removed after the concrete is set or remain in place permanently. One may utilize formwork that moves either vertically or horizontally (slip form paving) to allow extrusion and finishing of the concrete. Form liners and architectural form details can also be added to the basic structural formwork to create designs and patterns in the concrete for use as a decorative finish surface.
This topic includes information related to site-cast concrete placed during construction. Site-cast concrete is cast in forms on a cured slab and then placed in their final location. Walls are cast adjacent to their final location and then tilted up. Similarly, floor slabs are cast on the ground, one on top of another and then each are lifted into place.
