Abstract: Unloaded cable linear form was measured after the erection of common strands of suspension bridge． The vector height of unload cable linear form was amended and compared with the theoretical results． So the causes of error were analyzed． In order to study the influence of unload cable linear form on the main cable linear form of the bridge，a simple method was often used in the engineering practice to predict the main cable sag when the bridge was constructed． The error of main cable linear form is thought to be the same with the error of unload cable linear form． According to engineering practice， an alternative method of prediction of the error was proposed． Appropriate measures are taken to adjust the suspender length so as to ensure the linear form of the bridge meet the design requirements when the bridge is completed．

Key words: suspension bridge, unload cable linear form, prediction of the error of main cable linear form, suspender length correction

摘要： 悬索桥普通索股架设完毕后，测量空缆实际线形，修正计算后与理论值进行对比，并分析误差来源。对于空缆 线形误差对成桥线形的影响，工程上通常采用一种简单的方法预测成桥时的主缆垂度，即认为成桥时主缆的跨中标 高误差与空缆时的跨中标高误差相同。以工程实际为依托，采取另一种误差预测方法，并通过修正吊索无应力长 度，使成桥线形符合设计要求。

关键词: 悬索桥, 空缆线形, 成桥线形误差预测, 吊索长度修正