桩端后注浆工艺在古河道切割区域桩基设计中的应用

摘要

A project site in Shanghai in ancient river cutting area, the soil distribution has large ups and downs,with the use of partition design and the post-grouting bored pile,the number of piles, the duration and the cost can be reduced obviously. This paper gives an example of partition design of pile foundation in the complicated stratum. The results of static load test show that the bearing capaci-ty of unit pile length is improved by 80％. This project has some guiding significance for pile founda-tion design and the application of post-grouting bored pile in complex strata.%上海某工程场地受"古河道"切割,地层分布起伏较大,桩基设计时采用分区设计,并应用桩端后注浆工艺,从而减少了桩基数量,节约了工期和工程造价.本文结合该工程实例,讨论了在复杂地层中如何进行桩基选型和桩基分区设计,并分析了后注浆灌注桩的静载荷试验结果,试验结果表明采用桩端后注浆的灌注桩,单位桩长的单桩承载力设计值相比常规灌注桩可提高80％.该工程对复杂地层中的桩基设计和桩端后注浆工艺应用具有一定的指导意义.