During testing it was noted that in all cases the actual measured thickness of the specimens was slightly greater than the nominal value, suggesting that the length measurement uncertainty was 0.08 mm for the 3D laser. scanner, for detailed description Ref. [16]. This was especially true when producing structural steel in the transverse direction, where the actual thickness averaged 9.8% greater than nominal, compared to an average of 5.6% greater in the longitudinal direction. , for the IPE360 profile. However, as the calculated values ​​for tensile properties, presented in the following sections, take into account the actual thickness of the specimen, these differences between the actual and nominal dimensions will not affect the results presented. Significant residual stresses occur in most steel construction elements. Such stresses typically result from differential shrinkage upon cooling during I-channel manufacturing. However, the magnitude and distribution of residual stresses in hot-rolled members depend on the cross-section type and manufacturing processes and different models are offered. The residual stress is considered constant in the web although, when the depth of a wide flange section is large, it varies more or less parabolicly. In this paper, we attempted to study the influence of residual stresses on the tensile properties of structural steel. Residual stress distributions measured using X-ray diffraction techniques from the two structural steel samples are shown in Figures 4 and 5. The results of modulus, yield strength, tensile stress and maximum tensile strain for the IPE 360 profile and the IPE 400 profile are presented. and discussed in the following sections. Module, which describes...... middle of article ......s to characterize the mechanical properties of structural steel, International Journal of Steel Structures, 2013, submitted.18 Motra, HB, Dimmig -Osburg, A., Hildebrand, J.: Influence of measurement uncertainties on the results of predicting concrete creep under cyclic loading, in: Proceedings of the 8th International Conference on the Mechanics of Fracture of Concrete and Structures in concrete, March 10-14, 2013 /Toledo - Spain, ISBN 978 -84-941004-1-3, pp. 805-814.19 Motra, HB, Dimmig-Osburg, A., Hildebrand, J.: Quantification of the uncertainty in the creep deflection of a concrete beam subjected to cyclic loading, In: 11th International Conference on Structural Safety & Reliability, Columbia University, New York, NY, June 16 - 20, 2013, USA.20 ISO 6892-1:2009E (2009) International Standard, Metallic materials - Tensile testing - Part 1: temperature testing technique ambient.