The pre-bored grouting planted nodular (PGPN) pile is a new type of composite pile foundation. A large number of field test results have shown that the ultimate skin friction of piles under tension and compression has big differences. The total lateral friction reduction factor is defined as the ratio of shaft resistance between uplift pile and compressive pile. To investigate the differences of skin friction distribution of the PGPN piles under tension and compression in soft soils, a group of field tests were carried to obtain the load-displacement curves of piles under tension and compression, and then Abaqus was used to simulate test piles. The comparison between results of field tests and Abaqus simulation was used to validate finite element model. The results showed that the axial forces of piles under tension and compression have similar transfer characteristics; the uplift coefficient of the PGPN piles in soft soils is 0.5. The increase of diameter of enlarged pile tip has little effect on ultimate skin friction of piles under tension and compression. The total lateral friction reduction factor of the PGPN piles is a constant with the increase of the diameter of enlarged pile base.
GONG Xiaonan，XIE Cai，ZHOU Jiajin，SHAO Jiahan，SHU Jiaming
. A Comparative Study on the Static Drill Rooted Nodular Piles
Under Tension and Compression[J]. Journal of Shanghai Jiaotong University, 2018
, 52(11)
: 1467
-1476
.
DOI: 10.16183/j.cnki.jsjtu.2018.11.008
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