Performance of screw-shaft pile in sand: Model test and DEM simulation

A screw-shaft pile is a bored, cast-in-situ, displacement foundation solution. This study examines the performance of axially loaded screw-shaft piles by laboratory model tests, digital image correlation, and discrete element modelling. The results suggested that the screw section carried a greater vertical load than the corresponding section of the control pile; hence, the screw-shaft pile outperformed the control pile. The screw-shaft pile achieved better performance by influencing a larger volume of sand. The sand around the screw section exhibited enlarged cone-shape shear slips and contributed to gains in the pile capacity.