Publication Abstract

Proceedings - Fifth International Conference & Exhibition on Piling and Deep Foundations, 1994, Bruges, Belgium, (DFI)

The behaviour of continuous flight augered piles in soft clay
A. Lyndon, G.J.W. King & E.a. Dickin

Twelve piles of various diameters and lengths were installed using the continuous-flight auger boring technique and load tested in compression. The distribution of load transfer with depth was fairly linear as determined by measured displacements of extensometers within the piles. The shaft resistance therefore was approximately constant even though the clay has been shown to increase in strength with depth. Peak values of shaft resistance were of the same order as the average undrained laboratory strength of the clay, although they reduced significantly as the rate of movement decreased. Values of shaft resistance reduced when post peak movements were induced and approached the same constant value for all piles. Creep failure loads were also established and shown to correspond to consistent values of average shaft resistance, which were of the same magnitude as the constant values obtained at large movements.

 article #843; publication #36 (IC-1994)