偏转角对不同腐蚀程度钢绞线力学性能及蚀坑应力影响研究

Effect of Deflection Angle on Mechanical Properties and Pit Stress of Steel Strands with Different Corrosion Degree

研究不同轴偏转角下腐蚀钢绞线的力学性能,采用铜盐醋酸盐雾试验法对镀锌高强钢丝钢绞线分别进行静态腐蚀和应力腐蚀试验。对不同腐蚀程度钢绞线进行4个不同偏转角(0、10、20、30 mrad)静力拉伸试验,并利用Ansys Workbench对钢绞线蚀坑模型进行有限元分析,研究偏转角对不同位置的蚀坑应力影响规律。研究结果表明,钢绞线在受到拉力的作用下会加快钢绞线的腐蚀速率,显著大于静态腐蚀,导致钢绞线表面更容易产生缺陷。不同偏转角下腐蚀钢绞线的破坏一般发生在锚固端外丝,其破断力值随轴偏转角度增大而减小。钢绞线表层存在蚀坑时会产生应力集中现象,并且偏转角对锚固端位置的蚀坑应力贡献度显著,严重削弱钢绞线抗拉性能。

In order to study the mechanical properties of corroded steel strand at different coaxial deflection angles,static corrosion and stress corrosion tests of galvanized steel strand were carried out by using copper acetate spray test method.The static tensile tests of the corroded steel strand with four different deflection angles(0,10,20 and 30 mrad)were carried out,and the finite element analysis of the steel strand corrosion pit model was carried out by Ansys Workbench to study the effect of deflection angles on the corrosion pit stress at different positions.The results show that the corrosion rate of steel strand under tensile stress is significantly higher than that of static corrosion,and the surface of steel strand is more likely to produce defects.The damage of steel strand at different deflection angles occurs at the outer wire of anchor end,and the breaking force decreases with the increase of deflection angle of shaft.Stress concentration occurs when there is corrosion pit on the surface of steel strand,and the deflection angle contributes significantly to the corrosion pit stress at anchor end,which seriously weakens the tensile performance of steel strand.