Do chairs allow concrete to flow under reinforcement rods?

Chairs, used in concrete reinforcement, play a crucial role in maintaining the specified position of reinforcement rods (rebar) within a concrete slab or structure. Their primary function is to support the rebar at the correct elevation, ensuring it remains in the designed position throughout the pouring and curing process of the concrete. When concrete is poured, it is fluid and will flow under the rebar if there is sufficient space for it to do so.

By elevating the rebar above the bottom of the formwork, chairs help to ensure that the concrete can adequately flow beneath the reinforcement, enveloping it completely. This allows the concrete to bond effectively with the rebar, providing the necessary tensile strength and structural integrity to the final hardened concrete. Additionally, allowing concrete to flow under the rebar helps prevent any areas of weakness which could occur if the rebar were improperly positioned or if it experienced inadequate concrete coverage.

Thus, it is accurate to say that chairs facilitate the flow of concrete beneath the reinforcement rods, supporting the overall quality and effectiveness of the concrete structure being created.