Experimental Research On Mechanical Behaviours Of Structural Steel 16Mn At Elevated Temperatures

Mechanical behaviour parameters of structural steel at elevated temperatures are important basic data of steel structure's fire resistance design. Commanding the parameters has significance for enhancing security of steel structure in fire.In this paper,by using WAW-1000 computer control testing machine,heating device and specially designed deformation measuring appliance, 226 times experiments have been carried out to investigate mechanical behaviours of structural steel 16Mn from four steelworks at elevated temperatures by adopting loading under constant temperature test and heating under constant load test(which are named respectively overseas steady state test and transient state test).The main testing content are as follows:Stress-strain relationship,yield strength,modulus of elasticity,thermal expansion coefficient and deformation caused by both stress and temperature at 20℃-600℃.In the loading under constant temperature test,yield strength and modulus of elasticity of steel at elevated temperatures become lower and lower with rising of temperature.Regression formula of yield strength,modulus of elasticity,thermal expansion coefficient of steel at elevated temperatures has been drew.Analysed the dispersion of experiments.In this test, we defined the yield strength by adopting tangent-intersection method,and made comparison with the strength data obtained from other way. The result shows that yield strength is close to the detas of 0.5% yield strain.The heating under constant load test gave yield strength approximately according to yield definition,and compared with the result obtained from the test of loading under constant temperature.The result indicates that the strength of steel at high temperatures in the former test is lower than that in the latter.Regression formula of strain in the heating under constant temperature test was obtained,in which strength,strain and temperature correspond one to...