Comparison of Codes in Predicting Compression Capacity of Welded High‐Strength I‐Shaped Sections

This study presents a comprehensive investigation into the axial load‐bearing capacity of welded high‐strength steel (HSS) I‐shaped sections subjected to concentric compressive loading. Advanced nonlinear finite element (FE) simulations incorporating experimentally measured geometric imperfections, welding‐induced residual stresses, and nonlinear stress–strain behavior were developed and validated against previously reported experimental data covering a wide range of nominal yield stresses, cross‐sectional dimensions, and member slenderness ratios. The FE models demonstrated excellent predictive capability, when compared with experimental results. The experimental results were also employed to evaluate the predictive performance of 11 major international design code provisions: ASCE 10‐15, AISC 360‐22, AASHTO LRFD (2024), SSRC Guide, Eurocode EN 1993‐1‐1, BS 5950‐1, Russian SP 16.13330, Australian AS 4100, Indian IS 800, Chinese GB 50017‐2017, and the Japanese Code through comprehensive statistical analyses. The code predicted capacities showed some variations, with correlation coefficients between 0.92 and 0.95. IS 800, Eurocode 3, and the Chinese code were most conservative, underpredicting capacities by 20%–25%; AISC 360‐22, AASHTO, BS 5950, AS 4100, the Japanese code, and the Russian code were moderately conservative (9%–15%); ASCE 10‐15 and SSRC showed the closest agreement with test results. Classification of specimens by slenderness and steel grade revealed that prediction accuracy is governed primarily by each code’s inherent design philosophy rather than member slenderness, while conservatism increases systematically with steel grade, from conventional HSS (Q420–Q460) to advanced HSS (Q550–Q960). Compactness checks confirmed all specimens were non‐slender, indicating that capacity discrepancies arise from global buckling behavior rather than local plate element instability. These findings provide a unified, cross‐code benchmarking framework and practical guidance for engineers selecting design provisions for welded HSS I‐section columns.