Behavior Of Reinforced Concrete Beams Strengthened With External Steel Clad Subjected To Fire

RC beams strengthened with external steel clad is a strengthening method of externalsteel walled the concrete beam. Extension-story reinforcement can effectively improvethe bearing capacity and ductility of the concrete beam, little impact on cross section sizeand appearance, simple construction and short construction period and little impact on theenvironment, etc. So it has been widely used in the project. While the performance of steelangle degrades quickly under high temperature,which reduce even lost the reinforcementeffect. The structural component force deterioration, but it suffer the load afterreinforcement. The risk of the fire significantly outweigh the unreinforced member.Therefore, the paper study the performance of its fire-resistant. The primarily contents areas following:(1) Analysis the current achievement on thermal and mechanical properties of concreteand steel under high temperature, the modeling of thermal parameters and constitutiverelationship for steel and concrete are determined.(2) By using the software ABAQUS, establish the3D model of steel-concrete compositebeam. Based on the existing experimental data, verify the rationality of the model.(3) Analysis the temperature field distribution of RC beams strengthened with externalsteel clad and the effect of main parameters on the temperature field distribution.(4) The beam breadth, panel width, panel thickness, beam depth and the angle thicknessof the beams are analyzed on the beams’ influence of the resistance to fire the wholeprocess of curve. Through the analysis of the parameters, get the main influencingparameters.(5) On the basis of the influence of the resistance to fire the whole process of curve,research the change rule of fire resistance load ratio. Get the main influencing parametersabout fire resistance load ratio under high temperature.(6) The beam breadth, panel width, panel thickness, beam depth and the angle thicknessof the beams are analyzed on the beams’fire resistance. Get its main influencingparameters.