The right choice of steel – according to the Eurocode - Economical Bridge Solutions based on Innovative Composite Dowels and Integrated Abutments - page 14

2.1 Mechanical properties

The nominal values of the yield strength f y and the ultimate strength f u for structural steel
should be obtained by adopting the values f y = R eh and f u = R m direct from the product
standard, see Tab. 1, or by a Tab. drafted from this standard in EN 1993-1-1. It has to be no-
ticed, that the required yield strength decreases with increasing material thickness. This takes
into account the effect, that with the increase in material thickness, the addition of alloying
elements need to be higher to achieve constant yield strength over the thickness. However,
with the increase in addition of alloying elements, the carbon equivalent value raises and
welding becomes problematic. Welding is substantial to the application of structural steels.
Thus, the normative rules have considered this fact by lowering the required yield strength
for thicker plates to account for weldability.

Table 1: Mechanical properties at ambient temperature for thermomechnical rolled steels
[4]

The producers verify the conformity of their products with the standard by tensile tests,
in which for each section, the location of the test specimen is also defined, see e.g. Fig. 5 for
beams. The result of the tensile test is the stress-strain curve from which the relevant param-
eters, yield strength f y and tensile strength f u , are determined. These parameters are exempla-
rily indicated in Fig. 6, a typical stress-strain curve for a HISTAR ® 460 (or S460 steel grade
according to EN 10025-4 for thermomechanical rolled weldable fine grain structural steels).

Figure 5: Location of test specimen for tensile test