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What is? A Quick Guide to our industry.

A Steel fixer

A steel fixer is a tradesman who positions and secures steel reinforcing bars, also known as rebar, and steel mesh used in reinforced concrete on construction projects. The work involves following engineering drawings that detail the type of bar and the spacing used and setting out the work. The reinforcing bars are tied together with wire, which is cut using snips. Steel fixers are also responsible for attaching 'spacers' and 'chairs' that determine the amount of concrete cover.

Rebar

A rebar, or reinforcing bar, is a common steel bar, and is commonly used in reinforced concrete and reinforced masonry structures. It is usually formed from carbon steel, and is given ridges for better frictional adhesion to the concrete. It can also be described as reinforcement or reinforcing steel.

Reinforcement

Reinforced concrete is concrete in which reinforcement bars ("rebars") or fibers have been incorporated to strengthen a material that would otherwise be brittle. In industrialised countries, nearly all concrete used in construction is reinforced concrete.

Formwork

Formwork is the term given to either temporary or permanent moulds into which concrete or similar materials are poured. In the context of concrete construction, the falsework supports the shuttering moulds.

Formwork types:
Formwork comes in three main types:
  • Traditional timber formwork. The formwork is built on site out of timber and plywood or moisture-resistant particleboard. It is easy to produce but time-consuming for larger structures, and the plywood facing has a relatively short lifespan. It is still used extensively where the labour costs are lower than the costs for procuring re-usable formwork. It is also the most flexible type of formwork, so even where other systems are in use, complicated sections may use it.
  • Engineered Formwork systems. This formwork is built out of prefabricated modules with a metal frame (usually steel) and covered on the application (concrete) side with material having the wanted surface structure (steel, timber, etc.). The two major advantages of formwork systems, compared to traditional timber formwork, are speed of construction (modular systems clip or screw together quickly) and lower life-cycle costs (barring major force, the frame is almost indestructible, while the covering may have to be replaced after a few - or a few dozen - uses, depending on the applications).   

    • Re-usable plastic formwork. These interlocking and modular systems are used to build widely variable, but relatively simple, concrete structures. The panels are lightweight and very robust. They are especially suited for low-cost, mass housing schemes moladi.
  • Stay-In-Place Formwork systems. This formwork is assembled on site, usually out of prefabricated insulating concrete forms. The formwork stays in place (or is simply covered with earth in case of buried structures) after the concrete has cured, and may provide thermal and acoustic insulation, space to run utilities within, or backing for finishes.

    • Stay-In-Place Structural Formwork systems. This formwork is assembled on site, usually out of prefabricated fibre-reinforced plastic forms. These are in the shape of hollow tubes, and are usually used for columns and piers. The formwork stays in place after the concrete has cured and acts as axial and shear reinforcement, as well as serving to confine the concrete and prevent against environmental effects, such as corrosion and freeze-thaw cycles.