Design of Concrete Compressive Stress and Concrete Compression Struts, Simplified Analysis Method According to 6.8.7 (2)

\frac{σ_{c, m a x}}{f_{c d, f a t}} \leq 0.5 + 0.45 \frac{σ_{c, m i n}}{f_{c d, f a t}} \begin{array}{rcl} \leq & 0.9 & for f_{ck} \leq 50 N / mm ² \\ \leq & 0.8 & for f_{ck} \geq 50 N / mm ² \end{array}

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