大直径PHC管桩在高铁桥梁中的应用

Application of Large-Diameter PHC Pipe Pile in High-speed Railway Bridge

大直径PHC管桩具有单桩承载力强、抗弯拉性能优、耐久性好、施工快捷、造价低等优势,广泛应用于港口码头、工业与民用建筑及公路桥梁工程中。通过比较江苏省北部3个高速铁路项目的6座特大桥桥梁工程,论述了采用大直径管桩桥梁工点的地层性质及分布、桩基设计、桩长分布情况、大直径PHC管桩沉桩设备,根据大直径PHC管桩在简支梁桥墩基础中的应用情况,分析了沉桩方法及沉桩效果、桩基检测方法及结果等情况,并针对锤击法沉桩时出现问题的桥墩基础,提出了跟钻法施工、钻孔根植法施工、辅助射水法施工及变更为钻孔灌注桩等解决措施。

The large diameter PHC pipe pile has the advantages including strong bearing capacity,excellent flexural and tensile performance,good durability,fast construction and low cost.It is widely used in port,industrial and civil construction and highway bridge engineering.By comparing six grand bridges in three high-speed railway projects in northern Jiangsu province,this paper discussed the formation properties and distribution of working points of bridges with large diameter pipe piles,pile foundation design,pile length distribution and large diameter PHC pipe piles piling equipment.According to the application of large diameter PHC pipe piles in simply supported bridge pier foundation,this paper analyzed the method and the effect of sinking pile,the test method and the result of pile foundation.Considering the problems of bridge pier foundation in the process of sinking pile by hammer method,construction methods including the drilling method,drilling grounding method,auxiliary water shooting method and changing to bored piles were proposed.