首先引入损伤程度、损伤位置及损伤范围3个参数，用以描述拉索损伤状态的特征，然后建立损伤拉索垂度效应分析的方程。在此基础上，采用数值计算方法分析了不同几何形态、不同损伤状态的拉索垂度效应受纵横比和弦向长度等相关参数的影响规律，对比了垂度的精确计算值和垂度公式计算值间的误差。结果表明：垂度随纵横比变化的敏感区间为[0．997，1．003]，在此区间内损伤拉索跨中垂度逐渐增大，但是损伤前后垂度增长幅度逐渐减小；纵横比在[0．995，0．999）区间内，纵横比越大，误差越大；同一纵横比下，弦向长度越大，则采用现有垂度公式计算损伤拉索垂度所产生的相对误差就越大，但是最大相对误差小于1．7％；弦向长度为300 m、纵横比为0．997的拉索在损伤范围内垂度增量小于0．35 m，相对误差小于1．2％，说明现有垂度公式具有较高计算精度。%The three parameters,such as damage degree,damage location and damage range, were introduced to describe the damage characteristics of cable,then the sag effect analysis equations of cable with damage were built.Based on this,the influences of the aspect ratio and chord length of cables on the sag effect in different geometric figures and damage states were analyzed by using numerical computational method. The relative error between precise computational values and formula values of sag was compared. The results show that the variation of sag with aspect ratio in the sensitive scope is from 0.997 to 1.003,and the sensitive scope of aspect ratio is from 0 .9 9 5 to 0 .9 9 9 ,and in this scope the error by the classical sag formula increases with the chord length and sag-to-span ratio,but the maximum relative error is less than 1.7%.For a cable with chord length 300 m long and aspect ratio 0.997,the absolute sag augment is less than 0 .3 5 m and the relative error is less than 1 .2%.The sag formula is precise enough to predict the sag of cable with damage.
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