Influence Analysis of the Corrosion Factors Effect on the Corrosion Rate of Steel Wires of Main Cable of Suspension Bridge

The corrosion state of the steel wires in the main cable of suspension bridge is very important for the assessment of remaining life of the whole bridge. But until now, the assessment model has not been established. To solve this problem, the quantitative analysis of the factors effecting on the corrosion rate of steel wires of main cable is proposed based on the orthogonal analysis method in this paper. On the first, the Primary and secondary relationships of various factors affecting the corrosion rate of the main cable steels of suspension bridge is determined by using the 2kfactor design method. Then, the quantitative relationship between corrosion factors and corrosion rate is established based on the interaction of various factors. The theoretical analysis and data calculation show that, the NaCl concentration, relative humidity, stress, temperature and pH values are the main factors to effect the corrosion rate of main cable steel wires. The affection of NaCl concentration is the maximum, while the temperature is the minimum, Moreover, all the factors are independent with each other except the pH value, the pH value is interconnection with other factors. The influence analysis of the paper can provide a reliable theoretical basis for the assessment of suspension bridge main cable life.