Evaluating screw-shaft pile composite foundations in round Gravelly soil: A study using model tests and numerical
Tingting Yang1, Weicheng Zheng1, Yongli Xie1
1School of Highway, Chang'an Univ., Xi'an 710064, China.
Heliyon
|October 25, 2023
Summary
This study optimizes screw-shaft pile composite foundations by analyzing geometric parameters. Optimal design enhances bearing capacity and reduces settlement for improved construction and railroad engineering applications.
Area of Science:
- Civil Engineering
- Geotechnical Engineering
- Foundation Design
Background:
- Screw-shaft piles are widely used in construction and railroad engineering for their high bearing capacity and cost-effectiveness.
- Composite foundations utilizing screw-shaft piles require further investigation for optimal design.
- Accurate determination of geometric parameters for piles and cushions is essential for successful foundation design.
Purpose of the Study:
- To comprehensively evaluate the bearing capacity, settlement, and force characteristics of screw-shaft piles.
- To investigate the influence of key geometric parameters on foundation performance.
- To provide insights for optimizing the design of screw-shaft pile composite foundations.
Main Methods:
- A combination of indoor experiments and numerical simulations was employed.
- Key parameters scrutinized include root diameter, pitch, cushion modulus, and the proportion of the threaded portion.
- Performance was evaluated under various conditions to assess bearing capacity and settlement.
Main Results:
- Optimal side resistance for screw-shaft piles was achieved at a threaded section length of 0.44-0.55 times the pile length (L).
- Decreasing pitch enhances bearing capacity, with optimal performance at a pitch approximately equal to the diameter (D).
- Thread widths between 0.58D and 0.67D significantly reduced stress concentrations by ~22% compared to 0.5D, and a cushion modulus of 40-60 MPa minimized settlement.
Conclusions:
- The study provides critical insights for optimizing screw-shaft pile composite foundation design.
- Findings offer valuable guidance for engineers in selecting optimal geometric parameters for enhanced performance.
- The research contributes to the advancement of efficient and reliable foundation design in civil engineering projects.
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