后压浆钻孔灌注桩承载力分析与试验研究
Bearing Capacity Analysis and Experiment Research on ？？Post-grouting Bored Piles

针对后压浆钻孔灌注桩承载力难以准确确定的现状，提出基于现场试验的改进计算公式。采用平行对比法对某工程项目的普通钻孔灌注桩和后压浆钻孔灌注桩进行承载力现场测试，并结合单桩承载力理论分析，提出后压浆单桩承载力计算改进公式。结果表明：在条件相似的情况下进行测试时，采用后压浆技术可大幅提高单桩承载力，减小沉降量；采用改进公式计算的单桩承载力与现场测试结果相差较小，说明提出的公式是比较合理的；所确定的后压浆钻孔灌注桩承载力计算公式对类似工程具有重要的参考意义。
Aimed at the bearing capacity of post-grouting bored pile determined uneasily, the improved calculation formula was proposed based on the field test result. The parallel comparison method was adopted in some project. Vertical bearing capacities of the ordinary bored pile and post？？grouting bored pile were tested, and the bearing capacity of a single pile was analyzed theoretically. On this basis, the improved calculation formula of post-grouting bored single pile was proposed. The results show that the bearing capacity and subsidence for the single pile can be improved efficiently using the post-grouting techniques for bored piles in the similar condition. At the same time, the errors of computation and field test result are small when vertical bearing capacity of post？？grouting bored pile is calculated by the improved formula, so the proposed formula is reasonable. The determined calculation formula of bearing capacity of post-grouting bored pile can provide the experience for the similar projects