悬索桥主缆镀锌钢丝腐蚀过程及抗力变化试验研究  

Experimental Study of Corrosion Process and Resistance Changes of Galvanized Steel Wires for Main Cable of Suspension Bridge

作　　者：陈小雨[1] 唐茂林[1] 

机构地区：[1]西南交通大学土木工程学院,四川成都610031

出　　处：《桥梁建设》2018年第1期60-64,共5页Bridge Construction

基　　金：国家自然科学基金项目(51478391)~~

摘　　要：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420d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 ap-pearance 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 cor-rosion 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 ap-pearance 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, de-crease slowly at the stage of the galvanized layer corrosion and the delayed fracture of the wires oc-curs. At the stage of the wire base corrosion, the indices decrease fast and the brittle fracture of the wires occurs. In terms of the corrosion appearance and the losses of the corrosion and resist-ance 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.

关 键 词：悬索桥 主缆 镀锌钢丝 腐蚀 盐雾试验 抗力 破断力 

分 类 号：U443.38[建筑科学—桥梁与隧道工程] U441.4[交通运输工程—道路与铁道工程]