International Journal for Computational Civil and Structural Engineering (Jun 2023)

RESUDIAL STRESSES IN I-BEAMS AND ITS EFFECT ON RODS BUCKLING

  • Denis Konin,
  • Alexander Fimkin,
  • Alexander Olurombi

DOI
https://doi.org/10.22337/2587-9618-2023-19-2-172-187
Journal volume & issue
Vol. 19, no. 2

Abstract

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Stability calculation of steel rods should consider residual stresses, as well as local imperfections (bends, buckling). Codes of EU, USA, PCR considering difference between welded and rolled I-beams on compression and compression with bending. Coefficient of longitudinal bending has values that consider the presence of different values of residual stresses for welded and rolled I-beams. Russian code for the design of steel structures (SP 16.13330) for conditionally centrally compressed rods does not distinguish between methods of I-beams production. To determine residual stresses, a wide range of Russian profiles with different thin-walled was studied. Residual stresses for small-sized profiles were carried out by partitioning, for large I-beams - by drilling blind holes. The actual values of residual stresses in flanges and walls are established; most suitable curves for their approximation are selected. The actual shape of I-beams was also measured with a laser scanner. According to the results of curvature measuring, the limit and average values of local flanges deflection are established. Considering experimental studies, FE-modeling of rods with residual stresses was performed for both rolled and welded I-beams. In addition to code eccentricities, local shape imperfections were modeled. It is established that rolled I-beams show higher values of critical forces than welded ones by 8-16%. This is true for steels C355 and C390 with a lambda-factor of more than 4, and for C255 with lambda-factor more than 3. According to the study, a coefficient is proposed that increases the bearing capacity of rolled I-beams for medium and large flexibilities.

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