How is structural reinforcing steel commonly positioned in concrete structures?

The positioning of structural reinforcing steel in concrete structures is critical for ensuring the strength and integrity of the final product. When using small metal plastic chairs, reinforcing steel bars, or rebar, are held in the required position and height within the concrete formwork. These chairs are designed to support the bars above the concrete slab, ensuring that they are adequately covered by concrete once the concrete is poured. This positioning is essential because it helps maintain the necessary concrete cover over the rebar, which is vital for corrosion resistance and overall structural performance.

Using chairs also provides a consistent and reliable way to secure the rebar in place, mitigating any risk of displacement during the pouring of the concrete. Proper positioning is crucial to optimizing the load-bearing capacity of the structure, as the rebar is designed to handle tensile loads while the concrete manages compressive loads. Thus, this method of placement using small metal plastic chairs is widely accepted and practiced in construction to ensure that the reinforcing steel serves its intended function effectively.