DEM analysis of crushing around driven piles in granular materials

The capacity of driven piles in breakable weak sands is less than that of similar piles in strong sands. Numerical simulations using the PFC2D program, based on discrete element method (DEM), were used to investigate the penetration resistance of driven piles. The penetration resistance for an unbreakable granular material and a crushable granular material was examined. A soil composed of weak granular particles had a lower penetration resistance than a similar soil composed of uncrushab]e particles. Particle crushing caused the production of particles of different sizes. Breakage and particle rearrangement induced stress relaxation and caused the broken granular material to develop a lower resistance to pile penetration. Including a simplified tensile failure criterion in the DEM allowed crushing around piles to be analysed and visualised.

[1]  P. Cundall,et al.  A discrete numerical model for granular assemblies , 1979 .

[2]  Yukio Nakata,et al.  ONE-DIMENSIONAL COMPRESSION BEHAVIOUR OF UNIFORMLY GRADED SAND RELATED TO SINGLE PARTICLE CRUSHING STRENGTH , 2001 .

[3]  Malcolm D. Bolton,et al.  Discrete element simulation of crushable soil , 2003 .

[4]  A. Bishop.  The Strength of Soils as Engineering Materials , 1966 .

[5]  M. Bolton.  THE STRENGTH AND DILATANCY OF SANDS , 1986 .

[6]  Malcolm D. Bolton,et al.  Effect of particle size distribution on pile tip resistance in calcareous sand in the geotechnical centrifuge , 2000 .

[7]  Jerry A. Yamamuro,et al.  SIGNIFICANCE OF PARTICLE CRUSHING IN GRANULAR MATERIALS , 1996 .

[8]  Luis E. Vallejo,et al.  Crushing a weak granular material: experimental numerical analyses , 2005 .

[9]  Matthew Richard Coop,et al.  An investigation of the effect of soil state on the capacity of driven piles in sands , 2001 .

[10]  Denis Vallet,et al.  Numerical model of crushing of grains inside two-dimensional granular materials , 1999 .

[11]  Glenn R. McDowell,et al.  Discrete element modelling of yielding and normal compression of sand , 2002 .

[12]  Malcolm D. Bolton,et al.  Displacement and strain paths during plane-strain model pile installation in sand , 2001 .

[13]  Hans J. Herrmann,et al.  Fragmentation of grains in a two-dimensional packing , 1998 .

[14]  Richard P. Jensen,et al.  DEM Simulation of Particle Damage in Granular Media — Structure Interfaces , 2001 .

[15]  Mark Randolph,et al.  SCIENCE AND EMPIRICISM IN PILE FOUNDATION DESIGN , 2003 .

[16]  Yukio Nakata,et al.  MICROSCOPIC PARTICLE CRUSHING OF SAND SUBJECTED TO HIGH PRESSURE ONE-DIMENSIONAL COMPRESSION , 2001 .

[17]  J. D. Murff,et al.  Pile Capacity in Calcareous Sands: State if the Art , 1987 .