EXPERIMENTAL STUDY ON AXIALLY AND ROTATIONALLY RESTRAINED HIGH STRENGTH STEEL COLUMNS IN FIRE

摘要

Fire tests were performed to investigate the behavior of the restrained high strength Q460 steel columns when exposed to fire.Four full-scale columns were loaded axially and tested horizontal in a furnace dimension of 3.6m×4.6m×3.3m (width×length×height).Specimens were tested with several combinations of load level and degree of axial and rotational restraint under ISO-834 standard temperature curves.Temperature distribution and structural response of column in the furnace were recorded.The axial force in the column was generated by the strange gauge on the short column which supports bottom end of the column.The test results showed that the different combinations of tested parameters had a significant influence on the fire response of high strength steel columns.For the lower load ratio, the columns failed by global flexure buckling and for higher load ratio, the torsional buckling become significant.