Experimental investigation of behaviour of H-section steel beams (end-plate connection) under fire

The behaviour of four H-section steel beams(end-plate connection) under fire is investigated.The whole test is carried out using the self-made fire-test furnace.All the beams are full scale with 4 200 mm and 3 600 mm lengths.Steel beams are tested at two load ratios of 0.48 and 0.78.Through experiment,the distpibution of temperature field and deformation are obtained.The effects of end-plate connection and axial restraint on the behaviour of steel beams are also attained.The results of experiment reveal that local buckling and lateral torsional buckling take place in H-section steel beams under fire.The behaviour of H-section steel beams under fire is influenced by end-plate connection and axial restraint.When the beam undergoes a large deformation,compression force then quickly changes into tension force which supports the beam and reduces further deformation,that is to say,catenary action takes place.