8.1. Material characteristics

This section contains various tables depicting the material properties of the different steel grades.

Strength and stiffness

Table 8.1 Different steels and their properties.

Property	S235	S275	S355	S420	S460
Density \(ρ_k\) [kg/m³]	7850	7850	7850	7850	7850
Young’s Modulus \(E_k\) [N/mm²]	210 × 10³	210 × 10³	210 × 10³	210 × 10³	210 × 10³
Design Yield Stress \(f_{y;d}\) [N/mm²]	235	275	355	420	460
Design Tensile Strength \(f_{t;d}\) [N/mm²]	360	430	510	–	–
Yield Strain \(ε_{y;d}\) [‰]	1.12	1.31	1.69	–	–
Shear Modulus \(G_k\) [N/mm²]	8.1 × 10⁴	8.1 × 10⁴	8.1 × 10⁴	8.1 × 10⁴	8.1 × 10⁴
Coefficient of Thermal Expansion \(α\) [K⁻¹]	12 × 10⁻⁶	12 × 10⁻⁶	12 × 10⁻⁶	12 × 10⁻⁶	12 × 10⁻⁶

Higher steel grades are also available (up to S1100). The design rules stated in EC3 and this section only apply for the mentioned steel grades. The given values are only applicable to plates, flanges, etc with a maximum thickness of 40 mm acciording to NEN-EN 10025.

Stress-strain diagram

Note

\(ε_{y;d}\) : design yield strain
\(f_{t;d}\) : design tensile strength
\(f_{y;d}\) : design yield stress
tan α : E_d (Young’s modulus)

In ordinary calculation the distrubution of forces and structural checks are executed using linear elasticity. In practice this means that as soons as the steel starts to yield, the structure is assumed to have failed. Only the linear part of the diagram shown above is used. The maximum strain is limited by the values given in the material properties table.

Fig. 8.1 Stress-strain diagram steel.