Vertically loaded piles in non-homogeneous media

Abstract

SUMMARY Analytical methods for the axial responses of piles can be classified under three broad categories of (1) simple but approximate analytical solutions, (2) one-dimensional numerical algorithms, (3) full axisymmetric analyses using boundary or finite element approaches. The first two categories rely on the so-called load transfer approach, with interaction between pile and soil determined by independent springs distributed along the pile shaft and at the pile base. The non-linear spring sti⁄ness is related to the elastic—plastic properties of the actual soil partly by empirically based correlations and partly by theoretical arguments based on simplified models of the pile—soil system. This paper presents new closed-form solutions for the axial response of piles in elastic—plastic, non-homogeneous, media. The solutions fall in the first of the three categories above, and have been verified through extensive parametric studies using more rigorous onedimensional and continuum analyses. The e⁄ect of non-homogeneity and partial slip on the load and displacement profiles along the pile shaft is explored, and comparisons are presented with experimental data. ( 1997 by John Wiley & Sons, Ltd.