On the Axial Load-Bearing Behavior of Vibrated and Impact Driven Full Displacement Piles-PPT Presentation

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The study examines how vibratory installation affects the axial load-bearing behavior of full-displacement piles compared with impact-driven and quasi-statically installed piles. Vibratory pile driving is used in hydraulic engineering, harbor construction, and offshore projects because it can shorten installation times and reduce mechanical fatigue and noise. However, its effects on pile resistance are not well understood, and current design practice often accounts for this uncertainty by reducing assumed shaft friction and base resistance or by applying impact driving at the final depth.<br /><br />To investigate these effects, the researchers conducted model tests at a 1:10 scale in dry sand. The tests included vibratory installation, cyclic quasi-static installation, and impact driving, with the aim of isolating the dynamic effects of vibration on axial pile capacity.<br /><br />The results indicate that dynamic installation is associated with lower axial pile resistance. The researchers suggest that vibration-induced liquefaction may reduce shaft friction. They also observed that the vibrated pile failed in a more ductile manner than the cyclic quasi-statically installed pile.<br /><br />The findings highlight the need for a better understanding of how installation method influences pile performance and for improved design approaches that reflect these effects.

Keywords

vibratory installation

full-displacement piles

axial load-bearing behavior

impact-driven piles

quasi-static installation

pile resistance

shaft friction

base resistance

liquefaction

model tests