Uplift Behavior of Micro Pile - Pressure Anchor Composite Foundation

DOI

10.2991/978-94-6463-726-7_17How to use a DOI?

Keywords

Composite Foundation; Micro-pile; Pressure-type Anchor; Theoretical Analysis; Field Test

Abstract

A new type of micro pile pressure anchor composite foundation is proposed to address the geological conditions of the upper 2-4m soil layer and lower high-strength bedrock commonly found in mountainous and hilly areas. This composite foundation combines micro piles that facilitate mechanical excavation with pressure piles that have good tensile properties, effectively solving the limitations of traditional foundation types. In order to further explore the bearing mechanism of this composite foundation, a field pull-out test was designed and implemented in this paper, and the load displacement curve and ultimate bearing capacity under uplift load were obtained, elucidating the distribution law of axial force and tension sharing rate. The experimental results revealed the collaborative working mechanism of composite foundation, in which micro piles mainly bear tensile forces, while the grouting body of pressure type anchor rods bears compressive forces; In the initial stage of anti pull load, micro piles provide the main anti pull resistance. As the load continues to increase, the pressure type anchor gradually bears a larger proportion of the pull-out resistance. In addition, this study proposes a theoretical method to derive the relationship between load and displacement of composite foundations by comprehensively analyzing the load displacement curves of micro piles and pressure type anchor rods. Finally, a design method was proposed to calculate the required dimensions and material parameters for the micro piles and pressure type anchor rods when both the upper micro piles and lower pressure type anchor rods approach their bearing limits in the event of composite foundation failure.

Copyright

© 2025 The Author(s)

Open Access

Open Access This chapter is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/), which permits any noncommercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

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TY  - CONF
AU  - Qi Zhang
AU  - Bing Feng
AU  - Qing Lü
PY  - 2025
DA  - 2025/06/13
TI  - Uplift Behavior of Micro Pile - Pressure Anchor Composite Foundation
BT  - Proceedings of the 2024 6th International Conference on Hydraulic, Civil and Construction Engineering (HCCE 2024)
PB  - Atlantis Press
SP  - 160
EP  - 173
SN  - 2589-4943
UR  - https://doi.org/10.2991/978-94-6463-726-7_17
DO  - 10.2991/978-94-6463-726-7_17
ID  - Zhang2025
ER  -