灌注桩的成孔型式对桩侧摩阻力影响的研究

Research on Influence of the Pore Forming Type on Pile Side Friction Resistance

通过现场试验和室内模型试验,采用空底桩单桩竖向抗压载荷的方法测定桩侧摩阻力。研究结果表明,灌注桩的侧摩阻力会随着桩周土密实度的增长而提高;挤土成孔桩和螺旋灌注桩的侧摩阻力相对于非挤土桩有了明显提高;给出了非挤土挖孔桩、挤土成孔桩和螺旋挤土桩的极限侧摩阻力的计算。研究成果用以指导桩基础的设计和施工,能使之达到经济合理的目的。

In the field test and indoor model test, pile side friction resistance was determined by the method of vertical compressive load of single pile with empty bottom. Research results show that bored pile side friction resistance rises with increase of soil density degree,pile side fric- tion resistance of compaction pile and spiral compaction pile is obviously improved compared with that of digging hole pile. The pile side limit friction resistance calculation of digging hole pile, compaction pile and spiral compaction was conducted also. The research results can be used to guide the design and construction of pile foundation,and make it economic and reasonable.