2026-10-23T14:57:59Zhttps://gumushane-rdlopen.rawdatalibrary.net/oai/requestoai:gumushane-rdlopen.rawdatalibrary.net:gumushane/123782026-10-22T11:34:17Zopenairecom_gumushane_10000col_gumushane_10001com_gumushane_10007col_gumushane_10171Influences of chord pre-stress on CHS X-joints with high-strength-steel at various temperaturesOzyurt, E.Wang, Y.C.Chord pre-stressCircular hollow sectionElevated temperatureFinite element modelX-jointsThis study examines the influence of chord pre-stress on the behaviour and load resistance of Circular Hollow Section (CHS) X-joints with High Strength Steel (HSS) at various temperatures. This investigation uses a total number of seven hundred and four Finite Element simulation results to evaluate the level of accuracy of current Eurocode and CIDECT design guidelines in predicting the high-temperature resistance of these joints. The numerical simulations investigate the effects of changing brace-to-chord diameter (β), chord semi-diameter-to-thickness (γ), and brace-to-chord thickness (τ) ratios, as well as different prestressing levels (np) and temperatures (θ). The γ and τ ratios have a limited effect on the normalised joint strength, but the β ratio, and the prestressing level are highly influential. At ambient temperature, the CIDECT design approach is a more suitable method for calculating the chord pre-stress reduction factors for S355 joints. For HSS X-joints, the constant modification coefficient of 0.80 is inadequate, and this paper has proposed a new modification coefficient as a function of the pre-stress level. At elevated temperatures, the ambient temperature resistance of CHS X-joints can be modified by the reduction factor of the Young's modulus for S355 steel and that of the yield stress for S960 steel.Elsevier Ltd2025Articlehttps://rdlopen.rawdatalibrary.net/r/gumushane/12378https://doi.org/10.1016/j.firesaf.2025.1045060379-7112enFire Safety Journalinfo:eu-repo/semantics/closedAccessinfo:eu-repo/semantics/articlehttps://gumushane-rdlopen.rawdatalibrary.net/tr/items/gumushane/12378