铁路既有桥梁合修增建二线工程技术探讨

Research on the Engineering Techniques for Combining Adding a New Railway Line to the Existing Railway with Repairing Existing Bridges

铁路桥梁作为铁路工程的咽喉,其增建二线方案多为绕行原有桥梁新建施工,原有桥梁在二线建成后大多被废弃,既浪费资金且不节能环保。襄渝铁路桥梁工程部分采取了在既有遂渝铁路上桥梁墩台合体建设方案,即利用既有单线墩加宽成双线墩,其中既有墩顶帽、托盘及墩颈以下40cm的墩身凿除,其余墩身外包30cm现浇混凝土与增建二线同步施工,合体为一个整体墩台身。经过7a运营目前工程使用正常。对类似工程具有指导和借鉴作用。

As railway bridges are one of the most critical parts of the railway system,the most commonly-used method of adding a new line to an existing railway is,when the scheme of adding a new railway line to an existing railway line is considered,making the new railway line go by a roundabout route away from the existing railway bridges,which mostly will be abandoned after the second line is completed,and in which case not only much fund will be wasted but also much damage will be done to saving energy and protecting environment.To overcome these disadvantages,part of the railway bridge projects of the Xiang-Yu Railway adopt the construction scheme of combining the use of the existing piers and the building of new piers,namely,the existing single-line piers will be made use of and widened into double-line piers,the construction of which involves the removal of the pier cap,tray and the part within 40cm below the pier neck,and covering the remaining part of the pier with 30cm thick in-situ concrete,which will be placed in the meantime with the construction of the pier of the new railway line so that the two piers are combined into one.After 7 years of operation,the piers are found to be still in good working condition.This method may serve as a useful guidance and reference for other similar projects.