Experimental study on ferritic stainless steel simply supported and continuous beams

Abstract

Development of efficient design guidance for stainless steel structures is key for the increased use of this corrosion-resistant material by considering both nonlinear behaviour and strain hardening into resistance prediction expressions, together with the moment redistribution in indeterminate structures. With the aim of analysing the bending moment redistribution capacity of ferritic stainless steel beams, a comprehensive experimental programme on continuous beams is presented. These tests contribute to the assessment of EN1993-1-4 specifications, where no plastic design is allowed, and the classical and new plastic design methods available in the literature for indeterminate stainless steel structures. Four three-point and eight four-point bending tests are also reported for the assessment of current codified and revised cross-sectional classification limits, analysing the different methods for the prediction of the ultimate bending capacities of ferritic hollow sections. Additional test results reported by other authors in different stainless steel grades and carbon steel are also studied and presented. The analysis indicates that Class 1 cross-sectional classification limits are too optimistic for ferritic stainless steels and further research is needed for the extension of plastic design to these grades, although promising predictions of ultimate loads are obtained for austenitic and lean duplex stainless steels.Peer ReviewedPostprint (author's final draft

Experimental Study on Ferritic Stainless Steel RHS and SHS Cross-sectional Resistance Under Combined Loading

“…(6) and (8). Concerning CSM, it is appreciated that for the cross-sections where this method is applicable, the predicted compression resistances are more accurate, and also present lower scatter, being therefore more appropriate for the stockiest ferritic stainless steel RHS and SHS studied in this paper.…”

“…Tensile tests were conducted on these coupons to determine the stress-strain behaviour of the different parts of the cross-sections, which is generally different for those specimens extracted from the flat or corner regions of the cross-section, due to the effect of cold-forming processes. All the details regarding tensile tests have been widely described in Arrayago and Real [8],…”

“…Since these tests were performed in the same ferritic grade and cross-sections, the material characterization reported in [8] is applicable to the tests presented in this paper. Average material properties for flat and corner coupons are presented in Table 1, where E is the Young's modulus,  0.05,  0.2 and  1.0 are the proof stresses corresponding to 0.05%, 0.2% and 1.0% plastic strains respectively,  u is the ultimate tensile strength,  u is the corresponding ultimate strain and  f is the strain at fracture, measured over the standard gauge length of c A 65 .…”

“…These values were obtained from the experimental programme reported and analysed in Arrayago and Real [8], where four-point bending tests…”

Experimental study on ferritic stainless steel RHS and SHS beam-columns

“…This allowed for the evaluation of the cold-forming effects, which led into an increase in both the proof stress  0.2 and the ultimate tensile strength  u , while ductility was considerably reduced. Since the experimental programme described in this paper was part of a more general experimental programme, where different ultimate responses of ferritic stainless steel RHS and SHS elements were investigated, the more in detail aspects of the material behaviour of the analysed specimens has already been published in [12,13]. Therefore, a summary of the most relevant information regarding tensile coupon testing is described in this section.…”