Centrifuge modelling of an embankment stabilised with discretely spaced reinforced concrete piles

Abstract

This paper focuses upon the discrete piling method, whereby a line of spaced piles are installed across a slope, inducing soil arching in the failing soil mass and halting movement. However, the effect of pile location upon the slope is not yet thoroughly understood from a design perspective, with many publications making conflicting recommendations as to the optimal position. A program of centrifuge testing was undertaken to investigate the effects of both the position of the pile line upon a marginally stable embankment slope, and the method of pile installation adopted. Embankment models were tested both with and without the presence of driven and bored stabilizing piles, respectively, in various slope locations, and the slope crest deformation measured throughout testing. The results consistently indicated that regardless of pile type or location, some improvement in slope movement and stability is always achieved over the unreinforced embankment, with the model bored piles found to slightly outperform the driven piles. Installation between the toe and middle of the slope was found to be the optimal location.