长期海洋腐蚀环境下金属简支板振动行为退化机制OA

The corrosion environment has a significant impact on the dynamic characteristics of metal plate structures,posing a serious threat to structural safety and service life.An equivalent physical model of mass loss due to corrosion and structural mechanical properties is constructed,the influence laws of long-term corrosion environment on the vibra-tion characteristics of metal simply-supported plates is investigated.By equating corrosion to the changes in material elastic modulus and density properties along the thickness direction,the infiltration effect of corrosion inside the mate-rial and the residual mechanical properties of the surface corroded material are considered more finely.Based on the theory of elastic thin plate,the vibration control equation of the corroded plate is derived,and the accuracy of the nu-merical model is verified by the finite element method and the experimental results.The effects of typical regional atmo-spheric corrosion characteristics,initial corrosion rates,and structural size factors on the vibration characteristics of metal simply-supported plates are discussed.The results show that the vibration frequency of the metal plate decreases with corrosion time and is inversely correlated with the mass loss curve of corrosion;after 50 years of corrosion in a coastal industrial atmospheric environment,the fundamental frequency of the steel plate decreases by 19.09%,while the frequency of the aluminum plate decreases by only 1.05%.The method established in this study provides a theoretical basis for evaluating the vibration characteristics of metal structures serving long-term in corrosive environments and has guiding significance for engineering anti-corrosion design.