软土地区铁路桥梁墩台滑移病害整治技术研究

Study on Treatment Technology for Sliding Movements of Railway Bridge Pier and Abutment in Soft Soil Region

针对宁启铁路既有线某桥墩台位移病害,根据现场实测结果,建立力学模型进行理论分析,得出墩台滑动的主要原因是由于桩基侧向土体约束作用极低所致的结论,计算时采用自由桩长的假定,结合现场地形情况提出"纵向顶撑、横向限位"的桥梁加固原则,采用墩台之间设置水平系梁、桥台外侧设置横向限位桩、台后地基钻孔释放应力等整治措施。

In this thesis, for the disease of sliding movements of bridge pier and abutment of a existing line on Nanjing-Qidong Railway, based on the data measured from field, the theoretical analysis was carried out by establishing mechanical model. Then the conclusion was drawn： it was the shortage of lateral constraint force of the soil mass around the pile foundations that caused the sliding movements of bridge pier and abutment. On the basis of above-mentioned conclusion, with the calculation under the hypothesis of free pile length, and in combination with the actual field topography condition, the principle for the bridge strengthening was put forward： bracing longitudinally plus limiting transversely. Subsequently, the relevant treatment measures were adopted： installing the horizontal bracing beam among piers and abutments, installing the transverse limiting piles outside of abutments, boring into the earth behind abutments to release the stresses, and so on.