5. Sizing concrete parts

The resistance of a piece of concrete to a normal force is therefore a direct function of its cross-section.

When the stress exceeds the value allowed for concrete alone, longitudinal reinforcement can be introduced, with a specific strength greater than that of concrete. The correlation coefficient between the two materials is around 15, i.e. when 1 cm ² of steel is added to a concrete section, it can be assumed, at first glance, that everything happens as if 15 cm ² of concrete had been added. Steel and concrete work together. The calculation leads to the use of a so-called "homogenized" section, depending on the capacity of each of the materials.