Temperature Field Analysis Of The Concrete Box-girder Seted Fire Protection Coating

With the rapid development of national economy and traffic construction in our country,the number of traffic accidents is increasing, bring much of risks to transport infrastructure.Among them, the damage of bridge caused by fire also gradually cause widespread concern.The probability of the damage by fire on bridge is little, but it can cause huge losses to the lifeand property safety. Usually, spraing fire resistive coating on the outside of concrete bridgecomponent can reduce the probability of bridge damaged by fire, thus to improve the fireperformance of Bridges.In this paper, through using the finite element analysis method, the temperature field ofconcrete box-girde protected by fire retardant coatings is analysed and studied. The mainresearch content is as follows:(1)Article draw on the research about the high temperature thermal parameters and hightemperature mechanical properties of concrete referenced the scholars at home and abroad,systematic study and comparative analysis was carried out. The final analysis to determine thethermal parameters and mechanical properties of concrete box-girde in the temperature field,calculated as the foundation pad for later analysis.(2)Summarized the basic theory of heat transfer, and it is concluded the thermalanalysis method of bridge in fire temperature field; the various of fire heating curves aresummarized, based on the warming trend of the heating curve and its using range, this papercompares and analyzes to choose a suitable temperature curve for bridge is used to simulatethe bridge during a fire fire scenario.(3)By determining the thermal parameters of concrete and the thermal analysis methodand applicating of the finite element analysis software ANSYS, This paper has establishedthree sides protected by fire retardant coating without the flange of finite element model ofconcrete box-girder, and analyzed of fire prevention materials of thermal conductivity andthickness impacted on the distribution of temperature field of concrete box-girder. This paperdevelopment a yi language program named " calculation system V1.0about temperature fieldof the concretebox-girder protected by different fire resistive coating".(4) Based on bridge fire rating and numerical simulation analysis of temperature field byANSYS, This paper calculated a reasonable theoretical thickness of refractory material whenusing its different of thermal conductivity to protect box-girder section. Combining with theresearch contents and results, using yi language programm compilation " calculation systemV1.0about theory thickness of fire resistive coating concrete box-girde ".