Behavior of Rocket Piles Embedded in Sand under Static and Quasi-Static Cyclic Loading
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Pile foundations used in marine and onshore structures are often exposed to repeated axial loading, which can reduce their capacity and increase settlement over time. To address this issue, this study aims to evaluate the performance of rocket piles in sand and to understand how modifying pile geometry can enhance axial capacity under both static and quasi-static cyclic loading. A series of 1-g physical model tests were carried out to investigate the influence of sand relative density, pile slenderness ratio (L/D), fin-length ratio (Lf/L), fin-width ratio (b/D), fin location along the shaft, and surface roughness (Ra) on load–settlement behavior. The experimental results show that adding fins to the pile shaft significantly increases ultimate load capacity and reduces settlement compared to conventional smooth piles. The improvement is particularly noticeable under quasi-static cyclic loading, where fins help mobilize greater shaft resistance and limit the accumulation of settlement. Furthermore, larger fin-width and fin-length ratios provide greater performance enhancement. The main contribution of this study is the experimental evaluation of rocket piles under cyclic conditions and the development of practical design charts that allow engineers to estimate load improvement and settlement reduction based on fin geometry and surface characteristics, offering a more economical and efficient foundation solution in sandy soils.
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[1] El Naggar, M. H., & Wei, J. Q. (1999). Axial capacity of tapered piles established from model tests. Canadian Geotechnical Journal, 36(6), 1185–1194. doi:10.1139/t99-076.
[2] Ghazavi, M. (2008). Response of tapered piles to axial harmonic loading. Canadian Geotechnical Journal, 45(11), 1622–1628. doi:10.1139/t08-073.
[3] Lee, P. Y., & Gilbert, L. W. (1980). The behavior of steel rocket shaped pile. Symposium on Deep Foundations, 25 October, 1980, Atlanta, United States.
[4] Chan, S.-F., & Hanna, T. H. (1980). Repeated Loading on Single Piles in Sand. Journal of the Geotechnical Engineering Division, 106(2), 171–188. doi:10.1061/ajgeb6.0000920.
[5] Malik, N., Chen, W.-B., Chen, Z.-J., Wu, P.-C., & Yin, J.-H. (2024). Axial Cyclic and Static Behavior of FRP Composite Seawater–Sea Sand Concrete Piles Ended in a Rock Socket. Journal of Geotechnical and Geoenvironmental Engineering, 150(4), 04024013. doi:10.1061/jggefk.gteng-11529.
[6] Poulos, H. G. (1981). Cyclic Axial Response of Single File. Journal of the Geotechnical Engineering Division, 107(1), 41–58. doi:10.1061/ajgeb6.0001089.
[7] Poulos, H. G. (1988). Cyclic stability diagram for axially loaded piles. Journal of Geotechnical Engineering, 114(8), 877–895. doi:10.1061/(ASCE)0733-9410(1988)114:8(877).
[8] Jardine, R. J., & Standing, J. R. (2000). Pile load testing performed for HSE cyclic loading study at Dunkirk, France (Volume 2): Health and Safety Executive, Report No. OTO-2000-007.
[9] White, D. J., & Lehane, B. M. (2004). Friction fatigue on displacement piles in sand. Geotechnique, 54(10), 645–658. doi:10.1680/geot.2004.54.10.645.
[10] Cuéllar, P., Georgi, S., Baeßler, M., & Rücker, W. (2012). On the quasi-static granular convective flow and sand densification around pile foundations under cyclic lateral loading. Granular Matter, 14(1), 11–25. doi:10.1007/s10035-011-0305-0.
[11] Li, Z., Bolton, M. D., & Haigh, S. K. (2012). Cyclic axial behaviour of piles and pile groups in sand. Canadian Geotechnical Journal, 49(9), 1074–1087. doi:10.1139/T2012-070.
[12] Bhattacharya, S., Nikitas, N., Garnsey, J., Alexander, N. A., Cox, J., Lombardi, D., Muir Wood, D., & Nash, D. F. T. (2013). Observed dynamic soil-structure interaction in scale testing of offshore wind turbine foundations. Soil Dynamics and Earthquake Engineering, 54, 47–60. doi:10.1016/j.soildyn.2013.07.012.
[13] Lombardi, D., Bhattacharya, S., & Muir Wood, D. (2013). Dynamic soil-structure interaction of monopile supported wind turbines in cohesive soil. Soil Dynamics and Earthquake Engineering, 49, 165–180. doi:10.1016/j.soildyn.2013.01.015.
[14] Thomassen, K., Ibsen, L. B., & Andersen, L. V. (2017). Laboratory test setup for cyclic axially loaded piles in sand. Electronic Journal of Geotechnical Engineering, 22(3), 1089-1106.
[15] Azzam, W. R., & Elwakil, A. Z. (2017). Model Study on the Performance of Single-Finned Pile in Sand under Tension Loads. International Journal of Geomechanics, 17(3), 4016072. doi:10.1061/(asce)gm.1943-5622.0000761.
[16] Sakr, M., Nazir, A., Azzam, W., & Sallam, A. (2020). Model study of single pile with wings under uplift loads. Applied Ocean Research, 100, 102187. doi:10.1016/j.apor.2020.102187.
[17] Ramadan, N. O., Nasr, A. M., & Azzam, W. R. (2023). Model study of the geotechnical behavior of a single pile under torsional load in contaminated sand. Arabian Journal of Geosciences, 16(12), 674. doi:10.1007/s12517-023-11793-4.
[18] Nasr, A. M., Azzam, W. R., & Khater, A. I. (2024). Experimental studies on the response of single-finned pile under combined vertical-torsional loads in sand. Geomechanics and Geoengineering, 19(4), 586–604. doi:10.1080/17486025.2023.2296060.
[19] Sallam, A., Nasr, A., & Azzam, W. (2024). Effects of Simultaneous Torsional and Lateral Loads on Shaft Piles with Fins in Sandy Soil. Geotechnical and Geological Engineering, 42(5), 3777–3803. doi:10.1007/s10706-024-02757-w.
[20] Nazir, A., Azzam, W., Farouk, A., Nasr, A., & Aamer, F. (2024). Pullout Response of the Pre-displacement Bladed Anchor in Cohesionless Soil. International Journal of Geosynthetics and Ground Engineering, 10(2), 25. doi:10.1007/s40891-024-00530-w.
[21] Sakr, M. A., Azzam, W. R., & Wahba, M. A. (2020). Model study on the performance of single-finned piles in clay under lateral load. Arabian Journal of Geosciences, 13(4), 1–13. doi:10.1007/s12517-020-5068-7.
[22] Hagemann, A., Bienen, B., O’Loughlin, C., & Grabe, J. (2025). The response of pile foundations in sand to axial cyclic loading. 5th International Symposium on Frontiers in Offshore Geotechnics (ISFOG 2025), 9-13 June, 2025, Nantes, France.
[23] Zhou, P., Dai, F., He, B., Liu, Y., Yang, S., & Wei, M. (2025). Experimental investigation on the axial static and cyclic response of a single pile in medium-dense sands. Applied Ocean Research, 156, 104256. doi:10.1016/j.apor.2025.104493.
[24] ASTM D422-63(2007). (2014). Standard Test Method for Particle-Size Analysis of Soils. ASTM International, Pennsylvania, United States. doi:10.1520/D0422-63R07 .
[25] ASTM D3080/D3080M-11. (2020). Standard Test Method for Direct Shear Test of Soils Under Consolidated Drained Conditions. ASTM International, Pennsylvania, United States. doi:10.1520/D3080_D3080M-11.
[26] Sakr, M. A., Nazir, A. K., Azzam, W. R., & Sallam, A. F. (2016). Behavior of grouted single screw piles under inclined tensile loads in sand. Electronic Journal of Geotechnical Engineering, 21(2), 571–592.
[27] Basha, A., & Azzam, W. R. (2018). Uplift Capacity of Single Pile Embedded in Partially Submerged Sand. KSCE Journal of Civil Engineering, 22(12), 4882–4890. doi:10.1007/s12205-017-1715-2.
[28] Azzam, W. R., & Basha, A. M. (2018). Utilization of micro-piles for improving the sub-grade under the existing strip foundation: experimental and numerical study. Innovative Infrastructure Solutions, 3(1), 44. doi:10.1007/s41062-018-0149-0.
[29] Uesugi, M., & Kishida, H. (1986). Influential Factors of Friction Between Steel and Dry Sands. Soils and Foundations, 26(2), 33–46. doi:10.3208/sandf1972.26.2_33.
[30] Blanc, M., & Thorel, L. (2016). Effects of cyclic axial loading sequences on piles in sand. Geotechnique Letters, 6(2), 163–167. doi:10.1680/jgele.15.00155.
[31] Terzaghi, K. (1943). Theoretical Soil Mechanics. John Wiley & Sons, Hoboken, United States. doi:10.1002/9780470172766.
[32] ASTM D1143/D1143M-20. (2024). Standard Test Methods for Deep Foundation Elements Under Static Axial Compressive Load. ASTM International, Pennsylvania, United States. doi:10.1520/D1143_D1143M-20 .
[33] Butler, H. D., & Hoy, H. E. (1977). Users package for the computer storage and analysis of static pile load test data. Federal Highway Administration (FHWA), Washington, United States.
[34] Poulos, H. G. (1989). Cyclic axial loading analysis of piles in sand. Journal of Geotechnical Engineering, 115(6), 836–852. doi:10.1061/(ASCE)0733-9410(1989)115:6(836).
[35] El Naggar, M. H., & Sakr, M. (2002). Cyclic Response of Axially Loaded Tapered Piles. International Journal of Physical Modelling in Geotechnics, 2(4), 1–12. doi:10.1680/ijpmg.2002.2.4.01.
[36] Fahmy, A., & El Naggar, M. H. (2016). Cyclic axial performance of helical-tapered piles in sand. DFI Journal, 10(3), 98–110. doi:10.1080/19375247.2016.1211353.
[37] Robinsky, E. I., & Morrison, C. F. (1964). Sand Displacement and Compaction around Model Friction Piles. Canadian Geotechnical Journal, 1(2), 81–93. doi:10.1139/t64-002.
[38] Nazir, A. K. (2008). Effect of installation method in uplift capacity of piles in sand. Alexandria Engineering Journal, 23(3), 156-167.
[39] Shelke, A., & Patra, N. R. (2009). Effect of arching on uplift capacity of single piles. Geotechnical and Geological Engineering, 27(3), 365–377. doi:10.1007/s10706-008-9236-x.
[40] Hussein, B. S., Rahil, F. H., & Al-Neami, M. A. M. (2016). Bearing Capacity of Closed and Open Ended Pipe Piles in Clayey Soil. Engineering and Technology Journal, 34(8), 1615–1623. doi:10.30684/etj.34.8a.12.
[41] Fattah, M. Y., Al-Soudani, W. H., & Omar, M. (2016). Estimation of bearing capacity of open-ended model piles in sand. Arabian Journal of Geosciences, 9(3), 242. doi:10.1007/s12517-015-2194-8.
[42] Fattah, M. Y., Zbar, B. S., & Mustafa, F. S. (2021). Effect of soil saturation on load transfer in a pile excited by pure vertical vibration. Proceedings of the Institution of Civil Engineers: Structures and Buildings, 174(2), 132–144. doi:10.1680/jstbu.16.00206.
[43] Al-Suhaily, A. S., Abood, A. S., & Fattah, M. Y. (2018). Bearing Capacity of Uplift Piles with End Gates. Proceedings of China-Europe Conference on Geotechnical Engineering. Springer Series in Geomechanics and Geoengineering, Springer, Cham, Switzerland. doi:10.1007/978-3-319-97115-5_3.
[44] Franke, E., & Muth, G. (1985). Scale effect in 1g model tests on horizontally loaded piles. Proceedings of the 11th International Conference on Soil Mechanics and Foundation Engineering, 12-16 August, 1985, San Francisco, United States. (In French).
[45] Linos, M. L., & Dietz, M. S. (2005). The peak strength of sand-steel interfaces and the role of dilation. Soils and Foundations, 45(6), 1–14. doi:10.3208/sandf.45.1.
[46] Peng, J. R., Rouainia, M., & Clarke, B. G. (2010). Finite element analysis of laterally loaded fin piles. Computers and Structures, 88(21–22), 1239–1247. doi:10.1016/j.compstruc.2010.07.002.
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