• Deeks, A. D.

Abstract

<p>Pile jacking techniques use static load to install pre-formed displacement piles without the noise and vibration associated with dynamic methods. To quantify the axial base response of displacement piles jacked into sand, the pile jacking process has been faithfully replicated in a geotechnical centrifuge. Six pile installations and companion load tests are reported. The tests are shown to be highly repeatable, with a lateral COV of penetration resistance an order of magnitude less than that for typical field test sites. The non-linear base response of jacked piles is shown to be well modelled by a parabola, for use in 't-z' type analysis of pile response. The elastic solution for a rigid punch is used to link the base response to the operative soil shear modulus during loading. This parabolic model combined with the seismic CPT parameters G0 and qc, allows the initial stiffness, stiffness degradation and capacity at failure of the base response to be predicted.</p>

Topics

• impedance spectroscopy
• laser emission spectroscopy