一种斜拉索耐久性的评定方法

摘要

To accurately assess the durability and guide the maintenance of stay cables ,a method used specifically to assess the durability of PPWS stay cables is proposed .T his method is based on the current study of the probability of uniform corrosion depth and local point corrosion depth .The results of the finite element analysis were fit to gain the corresponding formulas of the load bearing capacity and corrosion degree of steel wires .And based on the probability theory ,the probability models of the load bearing capacity of both the steel wires and the stay cables after years of operation were induced .The design life of stay cables of an existing cable‐stayed bridge is 30 years ,the method was applied to assess the durability of the stay cables after serving 20 ,30 , and 40 years respectively .The feasibility and application value of the assessing method were veri‐fied by actual calculation .The assessing method can predict and evaluate the strength of stay ca‐bles at different serving stage ,provide reference for the selection of maintenance measures to stay cables as well as the determination of the stay cable replacement time .%为准确地评定斜拉索的耐久性，指导斜拉索养护，提出一种针对平行钢丝斜拉索耐久性的评定方法。该方法建立在已有的均匀腐蚀厚度和局部点蚀深度概率研究的基础上，利用有限元分析结果拟合得到钢丝承载力与腐蚀程度的对应公式，并通过概率理论推导得出了服役若干年后钢丝承载力和斜拉索承载力的概率模型。某在建斜拉桥斜拉索设计寿命30年，采用该方法评估了其20年、30年和40年的耐久性，通过具体算例演示验证了该评定方法的可行性和应用价值。该评定方法可以预估和评价在不同服役年龄时斜拉索的强度，为斜拉索养护措施的选择和换索时机的确定提供参考。