Centrifuge testing and numerical modeling of single pile and long-pile groups adjacent to surcharge loads in silt soil

Abstract

Centrifuge testing of both single pile and multiple long-pile groups was conducted using saturated silt soil to investigate the distinct response of piles under adjacent surcharge loads. The behavior of the piles in the soil was also determined using 3-dimensional (3D) numerical analysis. Through the verified model parameters, pile responses were explored from different surcharge loads and distances, with the effect of soil properties investigated in sequence. Results from centrifuge testing and numerical modeling indicate that the four pile foundations underwent different lateral displacements from bending moments due to the distinct soil deformation under consistent surcharge loading. Despite the lateral displacement of the pile cap, its incline also significantly affected the lateral displacement of the overlain pier. The settlement limit of the pile cap was also found to be the most reliable indicator of the pier’s current state compared to the lateral displacement and incline of the pile cap. For the single slit layer, each of the pile caps was found to bend toward the surcharge load, with all bending moments rotating in one direction. This is unique to those of double silt layers, which were found significantly affected by soil non-uniformity.