Simplified Analysis Procedure for Piles in Laterally Spreading Soil

Participants: Chris McGann, Peter Mackenzie-Helnwein and Pedro Arduino

In this project a procedure was established to appropriately account for the presence of a liquefied layer on the analysis of pile foundations subject to liquefaction--induced lateral spreading. For this purpose three--dimensional finite element models, considering a single pile embedded in a soil continuum, were used to compute representative py curves for various combinations of soil profile and pile diameter. Comparison of the py curves resulting from homogenous and layered soil profiles, in which a liquefied layer was located between two unliquefied layers, was used to identify reductions in the ultimate lateral resistance and initial stiffness of the py curves representing the unliquefied soil due to the presence of the liquefied layer. These reductions were characterized in terms of a reduction factor which follows an exponential decay model. Dimensionless parameters were proposed as a means of implementing appropriate reductions for an arbitrary soil profile and pile diameter.


Pedro Arduino
132 I More Hall, Department of Civil & Environmental Engineering, University of Washington, Seattle, WA, 98195-2700. Tel: 206-543-6777, e-mail: