Effect of temperature on natural frequencies of bridge structure of metallurgical crane

Abstract It is an important prerequisite for structural design and structural health monitoring to accurately obtain the natural frequencies and modal shapes of the structures, however, which are not only related to the stiffness and mass of the system itself but also affected by temperature, humidity, load and other factors. Therefore, the effect of environmental factors on the dynamic parameters of the structures should not be ignored in the process of dynamic analysis, especially for the structures which run in the complex environment such as bridge structures of metallurgical cranes. In this paper, two physical fields of solid heat transfer and solid mechanics in COMSOL are used to analyse the dynamic parameters of the bridge structure of a double-beam bridge crane based on the consideration of temperature effect and neglect of temperature effect respectively. The results show that, without considering the influence of ambient temperature on the material of crane bridge structure, whether the temperature effect is taken into account or not has no obvious effect on the form of structural vibration modal shapes. In addition, it can be concluded that the natural frequencies of each stage of crane -bridge structure increase under the condition of considering the influence of service ambient temperature, and the increase of natural frequencies of each stage also increases with the increase of convection air temperature at the bottom of the lower cover plate of the main beam.