Case Of Fire Resistance To Progressive Collapse Of Steel Frame Performance Analysis

The heat in the fire has an remarkable influence on the material performance and themechanics performance of the steel structure, the steel structures will lost most of theirintensity and rigidity when the temperature goes above550℃.The temperature in a room canreach to800～1200℃in a fire, so the steel structures are easily destroyed in a fire.The main function of a structure is to support the whole load above, and the lost of asingle part does not mean the destroy of the whole structure, especially for steel structures.The structure has the ability of load redistribution when parts of the its members are damaged,so the structure still can work as usual. Designing structures in the critical load bearing statesuffered from fire is more reasonable, if it is designed to resist progressive collapse. thereaction of the structure suffered from fire is being studied currently, The results for the safetydesign of steel works the fire fighting, reducing casualties were also practical significance..Inthis paper, the analysis of structure in fire is divided into two parts, including the fireresistance analysis of steel structure in fire and resist progressive collapse analysis underlocal damage occurs after fire.The whole process of steel frame suffered from fire is simulated based on the ABAQUSfinite element software. We established the heat transfer model of the steel frame under firecondition to research the overall fire-resistant under different conditions of different columnin fire, and the material non-linearity and the geometry non-linearity are consideredsynthetically. Then we established the mechanical model of steel frame, which has localdamage after fire condition, to analyze the resist progressive collapse ability of the structureafter local damage happened.For the fire resistant analysis, first of all, this paper analyzed the distribution situation ofsectional temperature of different models within an hour; secondly, the failure analysis todifferent models is carried on at high temperature and obtained the fireproof limit, criticaltemperature of steel frame and the mechanical properties of the adjacent members.