Concrete has been in use since Roman times and has become perhaps the most important material used in modern construction. It is essential to the design of commercial and residential buildings, and to the development of infrastructures such as roads, tunnels, airports, dams and tunnels.
In the agricultural sector, concrete plays an important part, for example in animal housing, culverts, underpasses and storage tanks.
Because of its waterproofing properties, concrete is used for storage and transport of water in settings such as reservoirs and canals. It forms an effective shield against radiation of all kinds and is therefore used for applications such as power plants and x-ray suites.
There are a number of different types of concrete, each with different applications and advantages:
Traditionally, concrete is mixed on-site, a practice may still be an efficient solution for large-volume projects
- where the volume required is unpredictable and
- a high-performance finish is not required
- can minimise waste.
Where there is a risk that bad weather is likely to hold up a project, on-site mixing is flexible but can lead to delays.
Ready-mix concrete is mixed at a plant before being delivered to the client and is then poured on-site.
It is particularly suitable for
- smaller projects, and when
- the quantity of concrete required is easily predictable.
- vulnerability to bad weather, and
- wastage in the event of miscalculation.
Precast concrete is the world’s most commonly used building material. Components are manufactured off-site in an enclosed factory, and then delivered in ready-to-use form.
Advantages to this system include:
- The process is quicker than moulding in situ.
- The concrete is always perfectly mixed, with superior durability and strength
- Immediate access to the site for follow-on trades.
- Components are delivered as needed, minimising on-site storage.
- Precast concrete can be produced in a huge variety of shapes, sizes, and finishes.
- Sound insulation. Precast concrete is an excellent sound insulator.
- Thermal mass. Precast concrete retains heat, would you sing the need 4 air conditioning and heating.
- Precast concrete lasts well and resists vermin, fungus, and pollution.
Reinforced concrete is a composite material in which reinforcing material, often steel, is used to overcome concrete’s low tensile strength. It is therefore useful in settings in which concrete is susceptible to twisting or stretching, such as in bridge beams and pressure vessels.
Prestressed concrete is a particular type of reinforced concrete produced using high-strength tendons which are tensioned during manufacture, improving the performance of the concrete. Tendons may be single or multi-wire strands or threaded bars and are generally made from steel or, in some modern applications, carbon fibre. Production of prestressed concrete requires a higher level of technical skill than other kinds of precast concrete.
Advantages of prestressed concrete include:
- Prestressed concrete is stronger more durable than reinforced concrete
- Sections are generally smaller than comparable reinforced concrete sections, so can be used for longer spans
- Sections are lighter and can be transported more easily