The next stage is adding a reinforcement.
This is a 3-part process:
Step 3: Placing reinforcement (where required)
Preparing and placing the reinforcing components
Positioning bar chairs and spacers
Positioning the reinforcing bars and/or mesh.
In Australia, you will find two types of reinforcement are most commonly used these are steel mesh or steel bars. The type of reinforcement to be used, its position and the concrete cover required will all be shown in the plans and specs for the job. The ‘cover’ is the amount of concrete which must cover the reinforcement to protect it from rusting. To ensure that the reinforcement sits at the correct height within a slab, it is supported by bar chairs. The reinforcement should be fixed to the bar chairs so that it does not move while the concrete is being added and compacted around it.
Spacers are also used to hold the reinforcement in the right position. Reinforcement should be fixed to spacers in the same way that it is fixed to bar chairs.
Keep the following tips in mind when installing reinforcement:
It must be clean and dry.
It must be free from flaky rust.
It must be free from grease.
Concrete must be properly compacted around reinforcement to ensure it forms a secure bond.
A space (called edge cover) is left between the edge of the slab and the reinforcement. NCC requirements specify a minimum of 40 mm.
Space, cut and tie the mesh or rebar while it is flat on the membrane before adding the chairs.
The following video provides a detailed explanation of how the reinforcements in concrete works.
