关键词: 锚索, 腐蚀, 多因素耦合, 演变规律, 加速试验

Abstract: The aim of this research is to truly and comprehensively understand the corrosion durability of anchor cable serving in the complex multi-factor corrosion environment. Indoor accelerated corrosion test of prestressed anchor cable under the coupling action of pH value, Cl^-, SO₄^2-, and stress near real load was carried out. The change characteristics of anchoring load of the anchor steel strand during the test were monitored. The appearance development of steel strand corrosion, the structural characteristics of corrosion products, and the time-dependent variation of mass loss per unit length and tensile strength loss rate were systematically studied by using material microscopic characterization method and mechanical property testing. The corresponding corrosion reaction mechanism was also analyzed. Results reveal that load stress intensifies the corrosion of steel strand. Compared with that in stress-free condition, the loss rate of tensile strength of steel strand in high stress condition is significantly higher. The simultaneous presence of SO₄^2- and Cl^- accelerates the corrosion of steel strand more than the single presence of SO₄² or Cl^-. Moreover,the corrosion degree in alkaline solution is relatively lower than that in acidic solution. After one year of accelerated corrosion test, the maximum mass loss per unit length of steel strand can reach 0.5 g/cm, and the maximum loss rate of tensile strength can reach nearly 50%. The research findings offer scientific basis and data support for evaluating and predicting the corrosion durability of anchor cable in real service environment.

Key words: anchor cable, corrosion, coupling factors, evolution law, accelerated test