Numerical Analysis And Research Of Reinforced Concrete Structure Under Fire

In recent years,the frequency of building fires is increasing in China,and the losses caused by building fires are also increasing.Under the high temperature of the fire,the properties of the reinforced concrete structure decrease with the increase of temperature,which leads to the decrease of fire resistance and the safety of the structure.In view of this situation,the temperature field of reinforced concrete structure under the condition of fire and high temperature is analyzed,and the structural field analysis is carried out,and the influence factors of the temperature field and the structure field are obtained,which can provide guidance for the fire resistance analysis of the structure.The following work is carried out mainly;(1)The results of the high temperature research at home and abroad,the thermal and mechanical properties of the materials at high temperature are described in detail in this paper,which provide theoretical data for the next fire simulation.On the one hand,the randomness of the building fire is very large,and on the other hand,there are many factors affecting the performance parameters of the material.Therefore,when the temperature field and the structure field are analyzed,some assumptions about the constitutive relation of the reinforced concrete and the concrete materials are needed.(2)Different building structures have different fire conditions.In this paper,the FDS fire simulation software is used to establish an office building fire numerical analysis model,and the heating curve of different temperature observation points,the distribution of the temperature field of the slice,the heat release rate curve of the fire are analyzed.The measured temperature rise curve and the standard temperature rise curve are different,so the measured temperature rise curve is used in the analysis of the structure field of the temperature field under the real fire field.(3)Taking the measured temperature rising curve from FDS as the data basis,the thermal force coupling analysis is applied to the ANSYS finite element analysis software.On the basis of the analysis of temperature field,the analysis of structure field is carried out on the basis of the analysis of temperature field,and the influence factors of the temperature field and deformation properties of reinforced concrete beams under fire are studied,which lays a foundation for the fire resistance analysis of reinforced concrete structures under fire.