Steel Components And Steel-framedstructures Of The Numerical Analysis Of Fire Behavior

The steel structures are widely used in modem building structures due to its advantage properties such as high strength, light weight and so on. However, the poor fire-resistant ability is also the weakness of the steel structures, in which its yield strength, when the temperature is up to 4000C, would decrease the half of the yield strength at the normal temperature, and the steel will lost most of its strength and rigidity when the temperature up to 6000C. Therefore, it is very important in the theory and practice to study the problem of fire resistance and fire protection of the steel structuresHigh-rate heating condition is a seldom but very dangerous event in fire. A nonlinear finite element analysis (FEA) method of basic steel element is introduced by choosing proper material constitutive models for steel beam and pillar.To develop a deep insight, this paper aims to provide the real ability of resisting fire of steel frame under practical fire condition. An advanced thermal and mechanical simulation techniques is adopted to assess the performance of frame structures under fire conditions with the finite element program ANSYS. The transient heat transfer is calculated, whereas the whole-process response of steel frame exposed to fire is calculated with double nonlinear finite element technique.The results indicate that the structure fire-resistant design method is based on the utilization of the inherent fire resistance of steel frames, and capable of predicting the fire resistance of steel frames. It also suggests that bare steel beams used with suitable fire-resistant columns could result in a global frame having improved fire resistance.