Studies On Cable Corrosion & Detection And Evaluation Method Of Structures In Service

The security performance of structures in service has drawn increasing attention,and the component performance,structure damages and service condition could all have significant impact on the safe use of structures.With the development of structural detection technology,the detection methods become more varied,but there is still a lack of systematic summary of it.And as an important structural component,there is little research on cable corrosion of cable supported structure.Though there're already some researches in cable corrosion of cable-stayed bridge,but the use of environment,structure form and load conditions are different,so it is necessary to study the impact of cable corrosion on cable supported structure.In this paper,salt spray test is conducted to explore the law of corrosion of steel wire strands,galvanized steel wires,semi-parallel wire stay cables and steel tie rods from the experimental phenomena.The coating and twisting of cables or strands will influence the corrosion and prevent the corrosion from developing inside to a certain extent.The evaluation of result of salt spray tests is carried out by weight-loss method and tensile test.The corrosion rate regularity and the change of mechanical properties of the four specimens are analyzed,and the equivalent conversion relationship between the accelerated test environment and the natatorium.The influence of cable corrosion on prestress losses is analyzed.By taking in the regulations for cable replacement in bridges,the impact of cable damage on cable supported structure is analyzed with the case of Qinyang Gymnasium by Midas.The detection items and methods are summarized and compared systematically.The content and methods of the security evaluation of structures in service are also introduced,and the grid structure of Tianjin Science Palace Hall is taken as an example to illustrate the evaluation process.