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This paper reports the second part of the study on the structural behaviour of stainless steel circular hollow sections subjected to combined axial load and bending moment. A series of numerical parametric studies is presented, using the validated finite element (FE) models from the companion paper, with the aim of generating further structural performance data over a wider range of stainless steel grades, cross-section slendernesses and combinations of loading. The considered parameters include the outer cross-section diameter, the ratio of outer cross-section diameter to thickness and the initial loading eccentricity. Both the experimentally and numerically derived section capacities were compared with the strength predictions determined from the current European code, the American specification and the Australian/New Zealand standard, allowing the applicability of each codified method to be assessed. The comparisons revealed that the current design standards generally result in unduly conservative and scattered strength predictions for stainless steel circular hollow sections under combined loading, which can be primarily attributed to the neglect of strain hardening in the determination of cross-section resistances and to the use of linear interaction formulae. To overcome these shortcomings, improved design rules are proposed through extension of the deformation-based continuous strength method (CSM) to the case of circular hollow sections subjected to combined loading. Comparisons between the proposals and the test and FE results indicate a high level of accuracy and consistency in the predictions. The reliability of the proposed approach was confirmed by means of statistical analyses according to EN 1990. [ABSTRACT FROM AUTHOR]

Abstract: Steel caging is an effective, economical, easily applied and widely used method of strengthening RC columns. Based on the results of two experimental studies, this paper proposes the finite element modelling of RC columns strengthened by a steel cage under axial loads and bending moments. The FE models were used to obtain the N-M diagrams of experimental cases in which a study was made of the improved resistance of RC columns strengthened with this type of strengthening technique. The paper also includes a comparison of different methods of connecting the cage around the beam–column joint and a parametric study to observe the influence of diverse parameters on the behaviour of the strengthened column, including: angle dimensions, number of strips, the yield stress of the steel used in the strengthening, the dimensions of the capitals at both ends of the column, concrete strength and the characteristics of the reinforcement used in the columns. Finally, the results of the various tests (experimental and numerical) described in the paper are used to be compared with three design proposals and the goodness of fit of each one is analysed. [Copyright &y& Elsevier]