悬索桥主缆与索鞍间侧向力理论计算方法与公式研究

为解决主缆与索鞍间侧面抗滑摩擦力难以准确计算及充分利用的问题，需开展主缆侧向力方面的相关研究。通过探究既有侧向力计算公式的理论基础，揭示其应用局限性；基于离散体接触关系，提出鞍槽内相互作用力的计算模型，建立侧向力理论计算方法，并分析误差影响；基于最小二乘准则进行分区间多元非线性回归分析，提炼出便于工程应用的实用计算公式；探讨了参数影响，并对比既有公式、理论方法及实用公式的计算结果；利用实用公式计算某实桥主缆抗滑摩擦力，并阐明其组成机理。研究表明：由Janssen公式演化而来的既有公式不适用于主缆抗滑计算；鞍槽宽度正偏差对侧向力存在有限的增大效应；增加钢丝列数，侧向力迅速增大并趋于稳定、侧向力分布曲线由负指数收敛型渐变为近线性；侧向力与摩擦系数呈负相关关系；实用公式与理论方法的结果吻合较好；两块竖向隔板贡献了24.5%的摩擦力，说明设置竖向隔板是充分利用侧面抗滑贡献潜力的有效措施。

Theoretical calculation method and formula for lateral force between main cable and cable saddle for suspension bridge

To solve the problem that the frictional resistance of lateral surfaces between main cable and cable saddle cannot be calculated precisely and cannot be used sufficiently, it is necessary to conduct related studies on the lateral force of main cable. By investigating the theoretical basis of the existing formulas for lateral forces, the application limitations of these formulas were revealed. Based on the contact relationships between discrete bodies, the calculation model for interaction forces in the saddle groove was proposed. Subsequently, the theoretical calculation method for lateral force was established, and then the effects of errors were analyzed. By applying the least square method to partitioned multivariate nonlinear regression analysis, the practical calculation formula was obtained. The calculation results obtained from the existing formula, theoretical method and practical formula, respectively, were compared, and the effects of parameters were discussed as well. The frictional resistance of main cable of an actual bridge was calculated by the practical formula, and its combination mechanism was clarified. The results show that the existing formula evolving from the Janssen formula is not suitable for anti-slip calculation of main cable. The positive deviation of the width of saddle groove has a limited enlargement effect on the lateral force. With the number of wire columns increasing, the lateral force increases rapidly and then becomes stable, and the distribution of lateral force gradually changes from negative exponential convergent type to near-linear type. The lateral force and the friction coefficient have negative correlation. The results of the practical formula agree well with those of theoretical method. Two vertical plates contributed 24.5% friction, implying that setting the vertical plates is an effective measure of fully exploiting the potential of lateral anti-slip contribution.