Experimental investigation into high strength Q690 steel welded H-sections under combined compression and bending

A total of 8 slender columns with four sections of different cross-sectional dimensions were tested successfully under eccentric loads. All columns failed in overall buckling about the minor axes of their cross-sections with significant material yielding. In some cases, plastic local plate buckling in the flange outstands became apparent at failure. After tests, all the columns were inspected closely, and no fracture in welding was found. As expected, these high strength Q690 steel welded H-sections were demonstrated to behave in various ways similar to those of conventional strength steel welded H-sections. Hence, these tests may be regarded to be confirmatory tests to structural behavior of Q690 steel welded H-sections under combined compression and bending. It should be noted that the measured failure loads were compared with the predicted resistances of these H-sections based on their measured geometrical and material properties according to various design rules given in EN1993-1-1, ANSI/AISC 360-16 and GB 50017-2003 respectively. Among all these three sets of design rules, EN1993-1-1 is shown to be effective and efficient in predicting resistances for high strength Q690 steel welded H-sections under combined compression and bending with properly selected parameters. Hence, EN1993-1-1 should be readily adopted by design and construction engineers in designing these Q690 steel welded H-sections under combined compression and bending.