Cert III Steelfixing cheat sheet

Reinforcement must be fixed to the positions and cover shown on structural drawings; cover is measured from the concrete face to the outside of the bar, not the bar centre.

Bar size is designated by nominal diameter in millimetres; the mass of a bar in kg/m equals 0.006165 × d², where d is the nominal diameter in mm (e.g. 16 mm ≈ 1.58 kg/m).

Lap length is a multiple of bar diameter, set by the designer from concrete strength, bar size, bar type and stress condition; laps are staggered so they do not all occur in one cross-section.

Standard bar bend diameters and hook geometries are specified in the reinforcement detailing standard; hooks are not bent tighter than the specified mandrel because tight bends fracture the bar.

Tying wire, bar chairs, spacers and ligatures hold bars during placing and concreting but are not counted as structural reinforcement unless the drawings say so.

Tolerances on bar position are limited: cover must never be reduced below the specified minimum, and spacers must be of a type and density that keep the cage stable under concrete pressure.

Safety obligations under work health and safety law require the person conducting the business to manage risks; the steelfixer must follow the safe work method statement, use nominated PPE and report hazards.

Environmental and waste controls apply to off-cuts, tie wire, packaging and bunded areas; waste is segregated and off-cuts are not left where they can become trip or penetration hazards.

Precast panel reinforcement is assembled in a jig to control dimensional accuracy; lifting inserts and cast-in plates are positioned to the placing drawing before the cage is closed.

Post-tensioning ducts and anchorages are fixed to the profile shown on the drawings, supported at close centres, and tied so they cannot displace during concrete placement.

Welded wire mesh is specified by wire diameter and pitch (e.g. 500 × 500 mm); sheet lap is typically one full mesh pitch plus 50 mm, or as detailed on the drawings.

Arc welding of reinforcement is only permitted where the designer approves it, because welding changes the metallurgy of the bar and can cause brittle failure at the heat-affected zone.

Mechanical couplers and threaded splices are alternatives to laps; they are installed to the manufacturer's torque or thread-engagement specification and inspected before concreting.

Pre-stressing and post-tensioning operations are high-energy tasks: exclusion zones are set around the anchorage during stressing and no person stands in line with a tendon.

Formwork and falsework interfaces matter to the steelfixer: the cage is checked for cover against the form face, and tie wire tails are turned into the concrete, not left against the formwork.

Inspection and handover require the fixed reinforcement to be checked against the placing drawing, with cover, laps, spacings and bar mark identification confirmed and recorded before the pour.