Evaluating Axial Elastic Pile Response from Cone Penetration Tests-Article

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The article presents a method for predicting the axial load–displacement behavior and capacity of piles using elastic continuum theory combined with seismic piezocone testing (SCPTu). The Randolph-type pile model represents soil stiffness and pile geometry to estimate pile-head movement, load transfer along the shaft, and the proportion of load carried by the base. It can also model more complex soil profiles and interpret both conventional top-down load tests and Osterberg-cell (O-cell) tests.<br /><br />SCPTu provides cone resistance, sleeve friction, pore pressure, and shear-wave velocity in one sounding. Cone measurements support direct or indirect estimates of shaft friction and end-bearing capacity; shear-wave velocity yields small-strain stiffness. A nonlinear modulus-reduction relationship then links this initial stiffness to pile response as loading approaches capacity, enabling prediction of a full load–displacement–capacity curve.<br /><br />Three case studies—in stiff clays at the University of Houston and Texas A&M, and clay till in Calgary—compare predictions with instrumented pile tests. The Houston and Texas A&M examples show good agreement in measured and predicted load–displacement response and load distribution. In Calgary, the model is adapted to interpret O-cell loading and reconstruct the response expected under top-down loading.<br /><br />The authors conclude that combining the elastic pile model with SCPTu data offers a practical, integrated approach to estimating pile stiffness, capacity, deformation, and axial load distribution.

Keywords

pile capacity

axial load-displacement

elastic continuum theory

SCPTu

Randolph-type pile model

soil stiffness

pile-head movement

load transfer

shear-wave velocity

O-cell test