具有滑移式散索鞍的悬索桥主缆架设分析

为分析悬索桥的主缆架设，首先建立了滑移式索鞍纵向复合圆曲线的数学描述方法，进而利用弹性悬链线的精确解，建立了两索鞍间索跨的分析方法，并用于确定由成桥几何控制参数确定的悬索桥成桥状态，随后通过移动鞍座寻找平衡位置，可得到空载时索鞍预偏量、各跨垂度、索股张力和索夹位置等重要参数。这种解析迭代法可以考虑散索鞍重量的影响，以及主梁的架设对索鞍支承面的弹性压缩。算例表明本文所建立的方法是正确的。工程算例还表明具有不同纵向曲线的索鞍对悬索桥结构的整体静力分析结果影响甚微，且忽略散索鞍的重量将使架设时锚跨侧索股的张拉力偏大。

Calculation of cable erection in suspension bridge with sliding saddles

In order to analyseis the erection of suspension bridge,the longitudinal curve of sliding cable saddle,assembled by arcs is first mathematically characterized.Based on the analytical solutions of elastic catenary,the method to analysis the cable span with two fixed ends is established,and finally the method to analyse cable span between two saddles is developd and is used to find the constructed state determined by controlling geometrical parameters,such as sag at middle span.Corresponding to the construction state,by sliding the saddles to the equilibrium state,important parameters such as pre-displacements of saddles,sags of cable spans,tension of wire strands and positions of hanger bands can be valued,and used to guide construction.The weights of anchorage cable saddles,and the elastic displacements of the saddle backstop induced by construction of beam,can be considered in this analytical iterative method.Examples show this method is correct.Engineering example shows saddles with different longitudinal curves have less effect to statics results of the structural analysis,and neglecting the weight of saddles enlarges the tensile forces of wire strands at anchorage span.If it is used to guide the construction,the elevation would be higher than expected in design.