Influence of prebored hole measures on compacting effects of jacked piles

Prebored hole is an effective construction measure of reducing compacting effects of jacked piles.An appropriate finite element model is established adopting the Drucker-Prager failure criterion and the finite deformation theory according to the actual process of jacked piles.This model can simulate the interaction of piles and soil and continuous penetration.The displacement fields under the prebored hole measures are studied through the finite element model,and the simulated results are compared with field test ones.The results show that the aperture and hole-depth are important factors for the compacting effects of jacked piles.Combination of the aperture and hole-depth can effectively reduce the compacting effects.With the increment of the aperture,the displacement will decrease under the same hole-depth.With the increment of the hole-depth,the displacement will decrease under the same aperture.