桩基承载力不足的影响因素及防治措施

钻孔灌注桩在有些桥梁工程应用中出现实际承载力低于设计值的情况。文中以某实际工程为例,从施工、设计方面分析钻孔灌注桩承载能力不足的原因,提出钻孔灌注桩在穿过较厚砂、卵砾石层后,残积土不宜作为基底持力层,并对桩基承载力不足提出防治措施。实践证明：锚杆静压桩是一种行之有效的桩基补强方案,对类似工程具有较好的借鉴作用。

Influence and Prevention Measures of Bearing Capacity Deficiency of Bored Pile

The real bearing capacity of bored pile was always less than the design value in some bridge engineering practices.Taking a practical engineering as an example,the reasons of bearing capacity deficiency of bored pile were analyzed from the aspects of construction and design.The residual soil can＇t be used as the substrate bearing stratum after the bored pile passed through the thick sand and gravel formation,and the corresponding prevention measures were also put forward.It is believed that the anchor jacked pile is proved an effective and intuitive reinforcement for the bored pile,which will be a good reference for some similar projects.