为了确定悬索桥主缆镀锌钢丝的剩余抗力和腐蚀外观之间的对应关系,采用中性盐雾试验对16组(共320根)镀锌钢丝试件进行420 d的加速腐蚀,观察钢丝的外观腐蚀过程,研究其腐蚀指标随腐蚀程度的变化过程,对腐蚀后的钢丝进行拉伸试验,测试其剩余抗力,并以此为依据对钢丝的腐蚀程度进行分级.结果表明:钢丝的外观腐蚀过程分为镀锌层腐蚀和基体腐蚀2个阶段;钢丝的质量、直径和破断力等指标在镀锌层腐蚀阶段降低较慢,钢丝发生延性断裂,进入基体腐蚀阶段后降低较快,钢丝发生脆性断裂;根据钢丝的腐蚀外观和腐蚀指标、抗力指标的损失,将钢丝的腐蚀分为8个等级,实桥检测时可通过腐蚀外观判断钢丝的剩余抗力.%To establish the correspondence between the residual resistance and corrosion appearance of the galvanized steel wires for main cable of suspension bridge,16 groups (totally 320 nos.) of the wire samples were acceleratively corroded for a period of 420 d,using the neutral salt spray test method,the corrosion process of the appearance of the wires was observed and the corrosion indices of the wires changing with the corrosion degrees were studied.The tensile tests for the corroded wires were made,the residual resistance was measured and based on the tests,the corrosion degrees of the wires were graded.The results show that the corrosion process of the appearance of the wires can be divided into 2 stages of the galvanized layer corrosion and the wire base corrosion.The indices of the wires,including the quality,diameters and breaking forces,decrease slowly at the stage of the galvanized layer corrosion and the delayed fracture of the wires occurs.At the stage of the wire base corrosion,the indices decrease fast and the brittle fracture ofthe wires occurs.In terms of the corrosion appearance and the losses of the corrosion and resistance indices,the corrosion of the wires is divided into 8 grades and in the inspection and testing of the actual bridges,the residual resistance of the wires can be judged through the corrosion appearance.
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