Response of open-end pipe piles to vertical dynamic load considering the effects of soil plug and soil disturbance during driving

Abstract

This paper presents an analytical solution for the vertical dynamic response of an open-ended pipe pile considering the radial inhomogeneity caused by soil disturbance. The governing equation of the surrounding soil is deduced on the basis of incremental deformations superimposed on an initial finite deformation, i.e. the soil disturbance. The effect of the radial expansion pressure of the soil plug after pile driving is investigated for the first time. By treating the soil plug as the additional mass attached to the pile shaft using the Voigt model, the densification of the soil plug is also considered. A parametric study is performed to illustrate the influence of the expansion pressure of both inner and outer sides of the pile wall and the soil plug on the vertical dynamic response of the pipe pile. The results indicate that the expansion pressure enhances the fluctuation of velocity admittance curves and the peak amplitudes of the reflected signal at both the pile toe and the soil plug top. Wall thickness of the pile influences the dynamic effects of expansion pressure and soil plug on the pile.