In the RF-CONCRETE Surfaces, I am trying to design surfaces and receive a high minimum reinforcement as a result of the SLS-design in some areas. In other areas, however, the minimum reinforcement is significantly smaller. What is the reason?


By default, the determination of the minimum reinforcement is based on a stress distribution in the tension zone before initial cracking (coefficient kc according to EN 1992-1-1 7.3.2 (7.2.)), which depends on the external loading (Figure 01). That is, by default, kc is variable.

Depending on the state of stress (e.g. pure bending, bending and tension, bending and compression, and pure tension), the minimum reinforcement can vary across the surface.

However, it is also possible to adjust the presetting. It is thus possible to select a bending constraint (kc = 0.4) or a centric constraint (kc = 1.0) (Figure 02).

As soon as a constant value for kc is assumed, the minimum reinforcement is independent of the external load and is applied uniformly over the structural component.

In this context, you can also select the direction in which the force should be considered (Figure 03)


Minimum reinforcement Restraint Centric Bending restraint


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