The Fire Experiment And Research Of Fire Resistance Ability About The Large Space Steel Roof

At,present,steel structure is widely used in the large space structure.Steel is sensitive to temperature.Steel has high strength at normal temperature.But steel is yielded easily at the high temperature.The lack of fire resistance ability is a difficulty,which shuld be considered carefully when it is designed.But there is no detailed specification domestic and overseas.Therefore,the research about the fire resistance ability of steel is very important.This paper is based on real engineering of steel roof truss.And a real fire experiment tested in a steel factory which had tall and large space.Tested the combustion characteristic of the abrasion resistant hydraulic oil,and the heat radiation intensity of the fire source.The change of temperature field and the spread of flur gas during the experiment was recordrd.Knew the regular about changes of the steel roof in the right above the fire by analyzing the influence degree of the top roof.According to theoretical calculation of fire temperature distribution and the experiment,the temperature of smoke was attenuated rapidly at vertical height due to the large space.And the flame height of medium-power could be 5m.And the temperature could be 1000? in flame core,800? 2m away from the face of oil.At 7m high,the temperature was under 100?.There were many windows on the top and side.It could help discharge the high temperature smoke,so that it avoided the temperature rising because of the gather of a lot of smoke.Therefore,the temperature of truss was below 50?.A finite element analysis by ABAQUS was carried,which included steel truss,steel beam and steel rack,so that we could analysis strain,strainand displacement change development of the steel turss structure.The result from the element analysis by ABAQUS showed that the temperature of the was between 400? and 550?without fire prevention under the total effect of dead load,live load and fire.Then the consequence of the test and finite element change annlysis was contrasted.It meaned steel truss and beam could bear the medium-power.The project will provide some basic data and have some help to the steel structure to resis the fire.