Fire Resistance Design Of Steel Structure Based On Transient Heat Transfer

The steel structures are widely used in modern building structures due to its advantage properties such as high strength,light weight, well shock resistant and 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 the fire occurs, severe damage or collapse will happen to the steel structure.Based on the research design of fire-resistance for steel structure in domestic and international,the fire-resistant performance of one plane steel-frame structures was analyzed by utilizing the thermal-stress coupling analyses of ABAQUS. The performance of physics and mechanics of steel at high temperature as follows:(1)This article analyzes the distributing situation of sectional temperature of the steel frame models within an hour utilizing the transient thermal analysis module of ABAQUS;(2)Carries on the failure analysis to the steel frame models at high temperature and obtains the fire-resistant limit and critical temperature of steel frame according to the distributing situation of sectional temperature;(3)According to fire-protection material nature as well as the fire-resistant limit and critical temperature of the steel structure, the thickness of fire-protection layer for steel structure and ask out the thickness of fire-protection layer of the steel frame models was calculated by this method. And the result of ABAQUS was compared with the related standard carries.At present,test-based fire resistance design method is used fire resistance design for steel structures. However,it is costly and hard to simulate the magnitude and distribution of load sand the end restriction conditions of the specimens in the structure. This article determines the fire protection protective measures of the steel structure reasonably by computing the fire-resistant limit, critical temperature and the thickness of fire-protection layer.The work did by this article may provide some suggestions and the reference for the steel structure fire protection design under the real fire function.