桥斜拉索腐蚀失效的分析

Analysis of Corrosion and Failure of Bridge Diagonal Tie Rods

分析了广东有四层防腐蚀层的斜拉钢索腐蚀失效的原因，因工艺技术上的缺陷，拉索内水泥浆体离析，使水及FDN高效减水剂等富集于上段；在较大水灰比，合一定浓度FDN高效减水剂及密闭条件下，上段水泥浆体会长时间不凝结；包裹拉索钢丝的水泥浆体长时间不凝结且未充满，产生电化学腐蚀。

The reason of corrosion and failure of bridge diagonal tie rods covered four protective layers was analyzed. Because of technological defects, cement paste in tie rod sleeves produced segregation, and some materials such as water, FDN high-efficient water reducer and etc. concentrated at higher part of tie rod sleeves. Under the conditions of high water/cement ratio, a certain consistency FDN high-efficient water reducer and hermetic surrounding, the cement paste bundling the steel bar could not be filled with paste. Then the electrochemical corrosion occured which mechanism was similar to that of micro-electric cell.