Weak-axis flexural buckling of cellular and castellated columns

Abstract

Cellular and castellated members are usually produced by performing cutting and rewelding operations on a hot-rolled I-section member. As illustrated in previous work, these operations will influence the residual stresses present in the members in a manner which is detrimental for the flexural buckling resistance. Up to now, this has not been considered in the limited amount of literature concerning the flexural buckling resistance of these members.In this paper, the weak-axis flexural buckling resistance is examined, taking into account the influence of the modified residual stress pattern and the modified geometry of cellular and castellated members. Therefore, the critical buckling load and the buckling resistance of simply supported cellular and castellated members were investigated numerically. In the numerical model, a modified residual stress pattern was introduced, based on earlier measurements. As the amount of measurements was relatively limited, the results of these simulations should be considered as preliminary results, in attendance of a confirmation of the utilized residual stress pattern.The results of the simulations illustrate the detrimental influence of the expected residual stress pattern modification on the buckling resistance. By comparing the results with the European buckling curves, preliminary best fit curves could be selected. This comparison was executed with a 2T approach, in which all cross-sectional properties are calculated for the 2T section at the centre of the opening.