Abstract: The formulas for calculating the non stress length of cable using catenary theory and parabola theory are derived. Taking Nancha cable stayed bridge of Nanjing Second Yangtz River Bridge as a numerical example,the difference of the non stress length of cable using the catenary and parabola theory is analyzed.It is concluded that using parabola theory to calculate the non stress length of cable can meet the requirement of precision.

Key words: cable stayed bridge, cable, catenary, parabola, non stress length

摘要： 推导了用抛物线理论与悬链线理论计算斜拉索无应力长度的公式,以南京长江二桥南汊斜拉桥为例,分析了用悬链线与抛物线理论计算斜拉索无应力长度的差别 .通过比较,认为对大跨度斜拉桥,用抛物线理论计算拉索无应力长度,完全可以满足精度要求

关键词: 斜拉桥, 斜拉索, 悬链线, 抛物线, 无应力长度