注浆挤扩灌注桩在工程应用中的关键施工技术

Key Construction Technology of Grouting and Expanding Cast-in-place Pile in Engineering Application

钻孔灌注桩具有对周围环境影响小、噪声小等优点,但桩身材料利用效率低。针对传统钻孔灌注桩的不足,介绍了一种新型的注浆挤扩灌注桩工艺。对钻孔灌注桩与注浆挤扩灌注桩进行了试桩试验,证明注浆挤扩灌注桩相比于钻孔灌注桩可极大地提高承载能力及抗拔能力,进而将原设计的钻孔灌注桩优化为注浆挤扩灌注桩。实践表明,优化做法既可以提高后注浆工法的可靠性,又可以大幅提高钻孔灌注桩的承载性能,减少了桩的数量及长度,具有良好的经济效益。

Bored pile has the advantages of less impact on the surrounding environment and less noise,but the utilization efficiency of pile body material is low.In view of the shortcomings of the traditional bored pile,a new technology of grouting and expanding cast-in-place pile is introduced.The trial pile tests for bored piles and grouting and expanding cast-in-place piles show that the bearing and anti-pulling capacity of grouting and expanding cast-in-place pile can be greatly improved compared with the bored pile,and the original design of bored pile is optimized as the grouting and expanding cast-in-place pile.The practice shows that the optimized method can not only improve the reliability of post grouting method,but also greatly improve the bearing capacity of bored piles,reduce the number and length of piles,and have good economic benefits.