The influence of correlation between initial axis curvature and cross-section rotation on the beam static resistance

Abstract

The paper deals with statistical analysis of the resistance of simply supported I-beams subjected to bending. The resistance was solved by applying the geometrically nonlinear solution. The influence of lateral-beam buckling on resistance is studied. Initial geometrical imperfections originating from the first eigenmode of lateral-beam buckling and from the cross section rotation at the stability lost were ascribed to the beams. These imperfections consist of initial axial lateral buckling and rotation of cross sections along the beam axis length. The correlation between the amplitudes of these imperfections is considered to be the parameter of solutions within the interval from -1 to 1. The influence of this correlation on the change of mean values and standard deviations of random resistance of beams with nondimensional slenderness close to 1 is studied. The imperfections mentioned were considered, together with geometrical and material characteristics of cross section and material characteristics of steel, to be random quantities.