The Detection And Identification Research On Steel Structure After The Fire

The steel structure has light weight and high strength, the strong plasticity and toughness, the superior seismic performance, the high degree of industrial assembling, short construction period and other advantages. In addition, it also used in industrial workshop, large span structure and the high-level structure. But due to high temperature has significant influence on the mechanical property of steel structure, which restricts the development of steel structure in practical project. Therefore, the group researches a steel structure damage detection and identification, which happened in a large steel structure factory building after the fire in Shenyang. We according to the change of material performance of steel structure in different temperature field, and the influence of high temperature effect on the structural reliability of fire. On the one hand, we can provide theoretical basis for fire resistant design for steel structure, on the one hand, we can provide a reference for steel structure after fire detection and identification, and complement the content of the existing test specification.In this paper, it bases on the example of detection and identification of the steel structure after fire, and we study the method of detection and identification of the steel structure after fire. Basically has the following several aspects:(1) First of all read a lot of literature about steel structure after fire performance, listed the fire phenomenon at home and abroad in recent years, illustrated the fire disaster harms to the society and people, studied the steel mechanical property testing, steel nondestructive testing method, the appraisal method of steel structures after fire and the component of fire resistance design method.(2) Tested the body of the steel structure workshop after fire, collected the measurements of the workshop steel structures after fire and describes the deformation and failure forms of steel structures, through the residue to determine the characteristics of site and expression, on the basis of mapping the isotherm of fire was studied after the change of strength of materials and components of the influence of the deformation of structures, and through the field survey data to determine the highest fire fire temperature distribution.(3) Combined with the actual construction engineering of steel structure workshop, according to field investigation and test data, the testing of high temperature components damage, for the steel structure after fire identification and rating according to the current specification. Completed the structural material mechanics performance appraisal, deformation of the bearing capacity of structure component identification, structure identification and structural connection and structure identification.(4) According to the summary of the component identification data, calculate the component of residual bearing capacity after fire, and the problems arising from the original structure component repair advice is given. Finally, discussed the analysis and appraisal of steel structure after the fire the issues in this paper, emphasis the key parts on steel structure after fire that can’t be ignored.This paper only study to one special specific engineering case on the fire detection and identification method of steel structure and its components, but because of the complexity and the particularity of the steel structure after fire, gave the researchers the difficulty and uncertainty to research. As a result, the detection and identification of steel structure after the fire by many problems still need further research and discussion.