18 April, 2018
Precast Concrete Components
Precast concrete is concrete that has been made in a mould under controlled conditions in a factory environment. There can be many types of precast components in a building. Precast panels and other units are prestressed to improve strength and performance and sealed before installation. Precast concrete can be used for floors, exterior and interior walls, concrete frameworks, staircases, wall cladding, plus a host of other construction uses.
With precast concrete you can use the mould as many identical panels as you require. The process is quick, the factory setting facilitates the setting up of good quality control arrangements which result in a high-class product each time. However, as the process only requires semi-skilled operators, labour costs are kept down. Furthermore, construction isn’t dependent on the weather. The precast concrete can be easily manoeuvered and transported to the site by lorry when the construction is ready for them. Once on site, they can be incorporated into the building quickly. In addition to prestressing, steel can be incorporated into each unit to provide additional strength.
Concrete Prefab Manoeuvering
Elements of Precast Concrete Building
Precast panels can be moulded for a variety of functions, which is why you can find all types of precast components in buildings of all types, including industrial units, superstructures such as bridges and flyovers, hospitals and residential homes.
Formwork is the name for the mould which provides the method used to create the precast concrete. The concrete is poured in and is supported by the formwork until it is strong enough to stand alone. Each unit can be manufactured to meet the architect’s requirements and can incorporate different joining and fixing solutions.
The type of building being constructed will determine the precast concrete requirements. Industrial buildings use precast columns and long beams, whereas domestic housing incorporates precast floors, which can be flat or ribbed, and walls.
· Precast Footings
Precast footings are foundations that are easy to install and use as soon as they arrive on site. They are extremely strong and provide a stable and level base from which to build. The installation of precast footings isn’t weather dependant and there is no mixing or other on-site preparation required.
Precast concrete beams are an integral feature of many buildings today. They are particularly suited to floor construction in houses, flats and commercial buildings and provide a low-cost flooring solution. Edge and spandrel beams which have a sill, go around the edge of the construction adding strength and with the sill providing the base from which floor slating can start. Spine beams are like spandrel beams but have two sills. Suspended beam and block floor systems utilising precast concrete minimise excavation requirements. Precast concrete lintel beams can be used over doors and frames generally and T beams are often incorporated into building design.
Manoeuvering of these beams though sometimes is not easy. However, thanks to the automatic lifting clamps this process can be handled more effectively and above all, much safer.
With both strength and flexibility, precast concrete columns add strength and flexibility and increase the life of any building. Columns can be made to the architect’s design and incorporate any special features or fittings. These columns can be erected as much as five times faster than in-situ methods of concrete production, so are labour saving. A high-quality finish can be achieved and furthermore they can be erected at night, even in residential areas, because there is none of the noise associated with making concrete on site.
· Shear Walls
Precast concrete wall panels can be used for both exterior and interior surfaces. They provide strength and lateral stability and when assembled can form a shear wall. Using walls panels and building them up is the most common method used and enables lateral-force resistance to be determined. They have been used in building projects as high as 30 stories but are more commonly seen in lower level constructions. The panels fit together easily, and the design can incorporate fixing mechanisms, such as steel edging plates that can be welded together for added strength. Examples of sheer precast concrete wall building includes elevator shafts.
· Partition Walls
Partition walls made from precast concrete can be lifted into position or the panels cemented together on site to provide a wall to ceiling partition wall solution. This type of assembly can be as much as six times quicker than alternative brick work. Panels are particularly suited to sound insulation, so are suitable for use in hotels, kitchens, hospitals, schools and apartments anywhere a degree of privacy is required, or noise from machinery needs to be deadened.
They also act as excellent fire retardants and the thicker the panels the greater the level of protection offered. Precast concrete panels also have good resistance to moisture so are suitable for use in wet rooms, bathrooms and kitchens. With most partition wall solutions, no plastering is required as the surface is already finished. Panels are strong enough to hang fittings from and the interiors can include ducts for wiring.