Analysis And Calculation On Fire-Resistance Of Steel Structure

The steel structures are widely used in modern building structures due to its advantage properties such as high strength, light weight and well shock resistant so on. The poor fire-resistance ability is the main weakness of steel structure in that its mechanical property such as strength and elastic modulus decrease severely in high temperature. When t fire occurs, severe damage or global collapse will happen to the steel structure.In china, test-based fire resistance design method is the prevailing fire resistance design method for steel structures. However, using the test-based fire resistance design method, it is hard to simulate the magnitude and distribution of load sand the end restriction conditions of the specimens in the structure. The ultimate fire resistance of the steel structure and the fire protection measures can be determined through calculation-based fire resistance design method. Therefore, a thorough study of the calculation-based fire resistance design method has great theoretical significance and practical value.Firstly, the internal force of the components of the steel structure which in local fire was analyzed in the paper. Based on the heat transfer principium, thermal-structure coupled analysis of plane frame structure had been carried out and the weakness of the steel frame in the fire had been determined. The influence between members exposed to fire and members isolated from fire was also checked in this paper. With the temperature rising according to the standard temperature graph we can get the deformation of the structure. Therefore, the thermal-structure coupled analysis can illustrate the real performance of the structure in fire.