Study on bearing capacity characteristics of rock socketed short pile in weathered rock site

  • Xinyuan Li
  • Xiaoyu Bai
  • Minyi Zhang
Keywords: bearing behaviour, in situ test, rock socketed short pile, strong weathered granite, ultimate bearing capacity,

Abstract

The bearing behaviour and load transfer mechanism of the rock socketed short pile were studied by the test and FEM of two different cases of 11 single short piles in a weathered rock foundation in Qingdao. The influences of aspect ratio and rock socketed length on the bearing behaviours of rock socketed short piles were discussed by FEM. The results show that the ultimate bearing capacity of rock socketed short piles is higher, and settlement is smaller, which means that they can satisfy the engineering demands and have high security reserves. Moreover, a change in the ultimate bearing capacity is not easily noticed with increasing of pile lengths, which demonstrates that the 11 piles have strong end bearing properties. The pile side friction peak decreases with an increase of the aspect ratio, as does the pile top settlement. Under different rock socketed lengths, the attenuation law of axial force is consistent; the pile top settlement decreases with the increase of rock-socketed length, and the ratio of base resistances to the bearing capacities decreases with the increase of the length. The research results can provide references for rock socketed short pile design in similar geological conditions.

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Published
2019-08-07
Section
Civil Engineering (1)