生产桥设置间距会影响到南水北调中线干渠的输水能力，因此合理的生产桥布置须即能保证干渠的输水能力，又能满足两侧居民的生产生活需求。论文在对南水北调中线京石段生产桥布置合理性分析的基础上，提出了长距离明渠工程生产桥优化布设应遵循的一般原则；进而考虑不同桥梁间距对渠道输水能力的影响特性，结合最大绕行距离得到跨渠桥梁的最大间距，与公路桥统筹考虑，拟定生产桥布置备选方案，并进一步基于综合绕行系数最小原则，建立了生产桥布置决策模型，确定明渠输水工程生产桥的具体布设位置。最后以南水北调中线京石段李家庄桥和西杜村桥为例，简述了该方法在明渠输水工程实践中确定生产桥布置方案时的应用。基于综合绕行最小原则的布置方案决策模型适用于长距离输水渠道上生产桥的选址优化，应用前景广泛。

The connection bridge spacing will influence the water conveyance capacity of the middle route of South-to-North Water Transfer. Therefore, reasonable layout of the cross ditch bridge for residents on both sides should not only ensure the channel capacity but also cater for the daily needs of the residents at both sides. On the basis of the layout rationality analysis for the middle route of the South-to-North Water Diversion project, this paper presented general principles of optimal layout about connection bridge on long distance open channel. And then, taking into account the influence of different characteristics of bridge spacing on channel capacity, the maximum distance of the cross ditch bridge was obtained combining with the longest tolerable detouring distance for residents, the connection bridge layout alternatives were drawn up, the layout decision model for selecting the site of connection bridges was established based on the principle of minimum synthetic detouring coefficient, and eventually the final specific location was determined. In the end, the method was applied to the case of the middle route of South-to-North Water Transfer (from Beijing to Shijiazhuang), which was proved satisfying. Decision-making model of layout scheme, based on the principle of minimum synthetic detouring coefficient, has suitable and extensive application in site optimization of the connection bridge on long distance water transfer channel.

河北省教育厅项目(ZC2016126)