后压浆技术对桩基承载力的影响

根据桩基现场原位试验，分析研究了后压浆技术对钻孔灌注桩承载力性状的影响。试验结果表明；浆液的作用消除了桩端沉渣和桩侧泥皮的影响，使土体固结，强度增大，改善了柱的传递性能，使桩侧摩阻力增加，轴力衰减速度加快；桩侧极限摩阻力提高50％以上，达到桩侧极限摩阻力时的沉降增大6倍以上，为桩端阻力的发挥提供了更大沉降距离；相同沉降量下后压浆桩桩端阻力提高幅度较大；浆液对桩侧阻力及桩端阻力综合影响提高了桩的极限承载力。

Bearing Capacity of Post-Grouting Pile Foundation

According to the data of test in situ, this paper analyzed the influence of post-grouting on the bearing capacity of boring pile.The test results show that the post-grouting diminished the influence of dregs at pile tip and mudcakes by the side of the pile;the soil around the pile can be consolidated,the strength and the property of pile transmission will be improved;the skin friction of the pile is increased,the axial force is increased by 50%;the post-grouting pile's tip resistance is increased rapidly at the same settlement;the intergrated influence of the post-grouting on the skin friction and the tip resistance can greatly increase the limit bearing capacity(of pile.) 3 tabs,10 figs,6 refs.