Distribution of Mechanical Properties of Steel Along the Curvature of Corrugated Web SIN Girders

This paper presents results from statistical tests on random parameters of strength properties of steel used to manufacture corrugated webs for SIN plate girders, depending on the place of specimen cut-out, that is, from the flat section or ridge of the wave. The tests were performed on specimens collected from 12 randomly selected corrugated sheets with thicknesses of 2, 2.5 and 3 mm, provided by the manufacturer of SIN beams. The analysis was used to select variation coefficients of yield strength <i>V</i>_Re = <i>D</i>(<i>R_e</i>)/<i>E</i>(<i>R_e</i>) and partial coefficients of yield strength <i>γ_m</i> for steel in flat and arched parts of the web. Metallographic and Vickers hardness tests were performed. Values of deformations and residual stresses were determined. The close correlation between the influence of the web plate shape and the strength parameters along the web curvature was demonstrated. Analysis of the initiation points of stability loss (IPLS points) revealed that the initiation of stability loss occurs in the area of the flat web sections. In addition to the influence of geometry, the influence of the change in yield strength, as identified in this paper, can be observed. Consideration of random features of yield strength and web thickness can lead to modifications in designing and calculating structures made of SIN girders.