Estimation of account the flanges in the direct calculation of stress-strain state parameters at normal sections of structural members

  • I. Židonis Šiauliai University


The present paper is a continuation of papers au-thors. The method and the formulae presented in the paper are designed for taking into account of the impact of the flanges and/or other strengthening /weakenings when mak-ing direct calculation (without the successive approxima-tions cycles) of the stress-strain state parameters at normal sections of bar-shaped structural members according to nonlinear material stress diagrams. The formulae are appli-cable for members that have no cracks (e.g. for the calcula-tion of the cracking moment) and for the sections between the cracks of the members that have cracks (for the calcu-lation of the stress-strain state of reinforced members, for estimating the deviation of the strain of the reinforcement from the plane sections). It is also possible to ignore the stresses. When the stresses of the tensile zone of the mem-bers are ignored, the formulae are applicable even to the sections near the crack (for the calculation of the cracking moment or of the reinforcement). Direct calculation is pos-sible when we know in advance the strain of any of the layers and when we know whether the flange and rein-forcement is subject of to compression or to tension. In other cases, the calculations need to be repeated. The cases when the stress diagrams are not curvilinear and when the members have cracks will be published as separate papers.