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. 2022 Jul-Sep;105(3_suppl):368504221113195.
doi: 10.1177/00368504221113195.

Evaluation of lateral capacity for flexible drilled shafts in cohesionless soils

Ssu-An Chou  1 , Yit-Jin Chen  1 , Jiunn-Shyang Chiou  2 , Anjerick Topacio  1 , Maria Cecilia Marcos  3
Affiliations

Evaluation of lateral capacity for flexible drilled shafts in cohesionless soils

Ssu-An Chou et al. Sci Prog. 2022 Jul-Sep.

Abstract

This study aimed to evaluate and improve the p-y curve method for use in the lateral analysis of flexible circular drilled shafts in cohesionless soils. Onsite circular drilled shaft lateral load test data from all over the world were collected, and the applicability of O'Neill and Murchison's p-y curve method was evaluated by comparing the measured values with the method's predicted values. Results showed that the current predictions were underestimated after applying the method to a database of flexible circular drilled shafts in cohesionless soils. Then, the difference (ΔQ) between the predicted value (Qp) and measured value (Qm) was normalized using the measured value (ΔQ/Qm) to determine the percent difference, and an average value of - 47% was produced. The difference ratio between the measured and predicted values was proportional to the diameter of the pile. To calibrate the prediction of the current method, this study applied two parameters (α and β) as modifications to reduce ΔQ. The parameters were decided by using the average difference ratio and average absolute difference methods. The reliability and consistency of the prediction of the p-y curve method were enhanced by applying the recommended modifying parameters. Specific design recommendations were also provided based on the proposed modifications on the original p-y curve.

Keywords: Lateral capacity; cohesionless soils; drilled shafts; flexibility factor; load test; p-y curve.

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Conflict of interest statement

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Figure 1.
Figure 1.
Winkler’s elastic foundation model (Winkler, 1867).
Figure 2.
Figure 2.
Relationship between coefficients C1, C2, C3 and the friction angle (Isenhower, et al. 2016).
Figure 3.
Figure 3.
Comparison of the influence of the parameter α on the original p-y curve method.
Figure 4.
Figure 4.
Comparison of the influence of the parameter β on the original p-y curve method.
Figure 5.
Figure 5.
Difference between the original predicted and measured values of flexible drilled shafts in cohesionless soils
Figure 6.
Figure 6.
Relationship between the pile diameter and the difference ratio ΔQ/Qm.
Figure 7.
Figure 7.
Prediction and measurement statistics of flexible drilled shafts improved by parameter α.
Figure 8.
Figure 8.
The predicted and measured statistics of the flexible drilled shafts improved by (3.0, 1.5), (3.0, 1.6), and (3.0, 1.7).
Figure 9.
Figure 9.
Difference between the predicted and measured values of flexible drilled shafts in cohesionless soils with modifying factors (α, β).
Figure 10.
Figure 10.
Sample load-displacement curve comparison.
See this image and copyright information in PMC

References

    1. Peek RB, Hanson WE, Thornburn TH. Foundation engineering. 2nd Edition. New York: John Wiley and Sons, 1974, pp.514.
    1. Poulos HG, Hull TS. Role of Analytical Geomechanics in Foundation Engineering. GSP 22, ASCE, 1989, pp.1578–1606.
    1. Chen YJ, Marcos MC. Applicability of Various load test interpretation criteria in measuring driven precast concrete pile uplift capacity. International Journal of Engineering Technology Innovation 2018; 8: 118–132.
    1. Chen YJ, Hsiao CC, Topacio A. Side resistance of circular drilled shafts socketed into rocks for serviceability and ultimate limit states. Advanced Technology Innovation 2020; 5: 156–165.
    1. Farooq QU, Shaath AB. Appraisal of hybrid foundations on loose granular soil of Western Saudi Arabia. Proceedings of Engineering and Technology Innovation 2020; 16: 13–22. 10.46604/peti.2020.5515 . - DOI

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