Geomechanics and Engineering

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Effects of inclined bedrock on dissimilar pile composite foundation under vertical loading

  • Kaiyu, Jiang (Key of Laboratory for RC and PRC Structure of Education Ministry, Southeast University) ;
  • Weiming, Gong (Key of Laboratory for RC and PRC Structure of Education Ministry, Southeast University) ;
  • Jiang, Xu (College of Civil Science and Engineering, Yangzhou University) ;
  • Guoliang, Dai (Key of Laboratory for RC and PRC Structure of Education Ministry, Southeast University) ;
  • Xia, Guo (Nuclear Industry Huzhou Survey Planning & Design Institute Co., Ltd.)
  • Received : 2022.07.04
  • Accepted : 2022.11.23
  • Published : 2022.12.10
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Abstract

Pile composite foundation (PCF) has been commonly applied in practice. Existing research has focused primarily on semi-infinite media having equal pile lengths with little attention given to the effects of inclined bedrock and dissimilar pile lengths. This investigation considers the effects of inclined bedrock on vertical loaded PCF with dissimilar pile lengths. The pile-soil system is decomposed into fictitious piles and extended soil. The Fredholm integral equation about the axial force along fictitious piles is then established based on the compatibility of axial strain between fictitious piles and extended soil. Then, an iterative procedure is induced to calculate the PCF characteristics with a rigid cap. The results agree well with two field load tests of a single pile and numerical simulation case. The settlement and load transfer behaviors of dissimilar 3-pile PCFs and the effects of inclined bedrock are analyzed, which shows that the embedded depth of the inclined bedrock significantly affects the pile-soil load sharing ratios, non-dimensional vertical stiffness N0/wdEs, and differential settlement for different length-diameter ratios of the pile l/d and pile-soil stiffness ratio k conditions. The differential settlement and pile-soil load sharing ratios are also influenced by the inclined angle of the bedrock for different k and l/d. The developed model helps better understand the PCF characteristics over inclined bedrock under vertical loading.

Keywords

Acknowledgement

This research was supported by the National Natural Science Foundation of China (52178317, 52078128), the Technological Research Program of Chongqing Municipal Education Commission (KJQN202101236), the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (22KJB560034). The authors are grateful for their support.

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