Simplified nonlinear method for settlement of root piles in multi-layered soils

LUO Xiao-guang; REN Wei-xin; YIN Yong-gao

doi:10.11779/CJGE202202019

Volume 44 Issue 2

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Chinese Journal of Geotechnical Engineering > 2022 > 44(2): 368-376. > DOI: 10.11779/CJGE202202019

LUO Xiao-guang, REN Wei-xin, YIN Yong-gao. Simplified nonlinear method for settlement of root piles in multi-layered soils[J]. Chinese Journal of Geotechnical Engineering, 2022, 44(2): 368-376. DOI: 10.11779/CJGE202202019

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Simplified nonlinear method for settlement of root piles in multi-layered soils

1.
School of Civil Engineering, Hefei University of Technology, Hefei 230009, China
2.
School of Civil Engineering and Mechanics, Xiangtan University, Xiangtan 411105, China
3.
Key Laboratory for Resilient Infrastructures of Coastal Cities, Ministry of Education, School of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, China

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Received Date: April 14, 2020
Available Online: September 22, 2022

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Abstract

Abstract

The root pile is a new type of pile, which improves the bearing capacity by penetrating a certain number of horizontal roots into soils from the reserved position of the piles. The load transfer model for the roots of a root pile is proposed based on the hyperbolic function, and a simplified nonlinear method for settlement of the root piles in multilayered soils is derived. An effective computer program based on MATLAB is developed for nonlinearly analyzing the load-settlement behavior of the root piles. The comparisons among the proposed method, other analytical methods and the root pile load test results on sites are carried out in terms of two real case root piles in Chizhou Yangtze River Highway Bridge in Anhui Province, China. It is demonstrated that the proposed method can achieve a good agreement with the measured results, and the load-settlement curve calculated by this method is more consistent with the real load-settlement characteristics of the root piles compared with that of the other analysis methods. The parameter study of the root piles shows that the load-settlement behavior of the root piles is not sensitive to the layout of roots and the load transfer parameters selected at root side-soil interface, but sensitive to the load transfer parameters selected at root base-soil interface.
- root pile,
- multi-layered soil,
- nonlinear settlement analysis,
- root,
- hyperbolic load transfer function,
- pile load test,
- parameter study

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References

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