为研究三塔悬索桥主缆与鞍座的抗滑特性，给出了三塔悬索桥主缆抗滑安全系数的简化计算方法。考虑活载作用下塔、缆变形以及加载跨与非加载跨主缆内力的平衡关系，推导鞍座处主缆抗滑安全系数的解析计算公式；建立有限元模型对公式进行验证；研究垂跨比、塔缆刚度比、恒活载比、跨径等主要设计参数对主缆抗滑安全系数的影响。研究表明：该公式可用于悬索桥初步设计阶段主缆抗滑安全系数的估算，能够为设计参数的合理取值提供理论依据。主缆抗滑安全系数随着塔缆刚度比增大而减小，当塔缆刚度比小于3时，增大塔缆刚度比，主缆抗滑安全系数迅速减小，当塔缆刚度比大于3时，塔缆刚度比对主缆抗滑安全系数影响较小；垂跨比对主缆抗滑安全系数的影响取决于桥塔刚度；主缆抗滑安全系数随着恒活载比值及跨径增大而增大。%To study anti⁃slip characteristics of main cable and saddle of three⁃tower suspension bridges, a simplified calculation method for calculating anti⁃slip factor was proposed. Analytical formulas for calculating anti⁃slip factor were deduced and finite element models were established to verify formulas. The effects of some important design parameters on the anti⁃slip factor were studied. Analysis shows that the analytical method has a high accuracy, which can be used in preliminary design of three⁃tower suspension bridges. With the ratio of tower and cable stiffness increasing, the anti⁃slip factor decreases; when the ratio of tower and cable stiffness is less than 3, changing the ratio of tower and cable stiffness has a great influence on the anti⁃slip factor. When the ratio of tower and cable stiffness is more than 3, the anti⁃slip factor is not sensitive to the ratio of tower and cable stiffness. Effect of sag⁃to⁃span ratio to the anti⁃slip factor depends on the tower stiffness. With the increment of span length and the ratio of dead load and live load, the anti⁃slip factor increases.
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