多塔悬索桥全竖向摩擦板式抗滑方案

为解决主缆与中主鞍座间的滑移对多塔悬索桥结构设计的约束，研究在鞍座内增设竖向摩擦板的抗滑方案，并制作用于探明设有竖向摩擦板后索股滑移特性的试验模型，考虑试验索股数目的影响，开展共4种工况的测试研究. 结合既有侧向力研究成果，构建主缆滑移分析模型；以首座采用混凝土中塔的三塔双层悬索桥(温州瓯江北口大桥)为工程实例，通过调整竖向摩擦板数量进行抗滑设计比选. 结果表明：在不平衡力持续加载下，主缆索股表现为自上而下的分层滑移现象；增设竖向摩擦板是提高主缆抗滑能力的有效途径；所建立的滑移分析模型可用于设置竖向摩擦板时的主缆抗滑研究；列间全置竖向摩擦板可为主缆提供相对最优的抗滑性能.

Anti-slip scheme of full-vertical friction plate for multi-pylon suspension bridge

The anti-slip scheme of adding vertical friction plate to the saddle was investigated, in order to solve the structural design constraint of multi-pylon suspension bridge caused by slip between the main cable and the middle saddle. The corresponding test models were made to investigate the slip behavior of cable strands when equipped with vertical friction plate. Totally, four experimental cases were carried out considering the effects of the number of strands. Combined with the existing studies on the lateral force of main cable, a slip analytical model was established. A three-pylon double-deck suspension bridge that firstly adopted concrete mid-pylon, namely the Oujiang River North Estuary Bridge, was taken as a practical engineering case; and the comparison study for anti-slip design was conducted by adjusting the number of vertical friction plates. Results show that, with the continuous loading of the unbalanced force, the cable strands display layered-slipping phenomenon from top to down obviously. The friction resistance of the main cable can be enhanced effectively through adding vertical friction plate. The proposed analytical model is applicable to the anti-slip design of the main cable when the vertical friction plate is added. Setting vertical friction plates among saddle notches can provide the main cable with the relatively best anti-slip performance.