Method For Fire Resistance Design Of Regular Hexagon Castellated Composite Beams

With the wide application of honeycomb composite beam structure,its fire resistance is closely related to people's life and property safety,and has received more and more attention.Studying the fire resistance performance and fire resistance design method of honeycomb composite beam structure is of great significance for promoting and improving the fire resistance performance of honeycomb composite beam structure.Based on the research on the fire resistance test of honeycomb composite beams,the finite element software is used to establish the fire resistance analysis model of the hexagonal honeycomb composite beam.The fire resistance performance of the honeycomb composite beam is considered comprehensively.The fire resistance design method of the honeycomb composite beam is studied and the fire resistance is summarized.The empirical formula of the limit simplified calculation formula and the critical temperature provides a reference for the fire resistance design of related projects.On the basis of summarizing the research results of domestic and foreign scholars and norms on the thermophysical properties and mechanical properties of materials,the thermal analysis parameters of materials suitable for this study were selected,and the finite element analysis of the hexagonal honeycomb composite beam specimens was carried out to obtain simulated fire conditions.The distribution of temperature field and the law of change.The results show that the temperature field variation of honeycomb composite beam is similar to that of ordinary beam,and the rate of temperature rise directly is the fastest.There is a large temperature difference between the upper flange of the honeycomb beam and the web and the lower flange.The thermal conductivity of concrete is poor,and the floor is There is a significant temperature gradient in the honeycomb beam web,but as time increases,the temperature gradient difference gradually decreases.The fire resistance performance of the regular hexagonal honeycomb composite beam under different parameters is analyzed.The time-displacement curve is compared with the existing test results to verify the accuracy of the finite element model and the correctness of the analytical method.The effects of load ratio,honeycomb beam length,concrete slab thickness,opening ratio and section size(honeycomb beam height,web thickness,flange width and flange thickness)on the fire resistance of honeycomb composite beams were investigated.The results show that the load ratio,honeycomb beam height,honeycomb beam length and concrete slab thickness are the main parameters affecting the fire resistance of honeycomb composite beams.The practical calculation formula of the fire resistance of the hexagonal honeycomb composite beam is proposed.The critical temperature database under the influence of each main parameter is established by using the finite element software.The associated influence parameters are combined and the empirical formula of the critical temperature of the hexagonal honeycomb composite beam is proposed.The fire protection design of the hexagonal honeycomb composite beam is proposed,and the fire resistance design method suitable for the hexagonal honeycomb composite beam is proposed,which provides a basis for the fire resistance design of the hexagonal honeycomb composite beam member to ensure the force of the component in the event of fire.And the fire resistance limit is in line with the original intention of the design.