Influence of relative density on the degree of soil plugging of pipe piles driven in sandy soils

Abstract

Bearing capacity of open-ended piles installed in sandy grounds depends heavily on the degree of soil plugging. A fully-plugged pile generally produces a bearing capacity similar to a closed-ended pile. In this paper, soil plugging behavior of inner-sleeved open-ended piles driven in sandy soils is discussed. The piles were penetrated in dense and loose sands. The degree of soil plugging is discussed using a modified version of incremental filling ratio. The results suggest that loose sand produces a relatively higher degree of soil plugging. The results also indicate that the open-ended piles penetrated in dense sand produce larger penetration resistance than loose sand. The results further suggest that a pile of a taller sleeve produces a larger resistance than shorter counterparts in both loose and dense sands. The results also indicate that a pile of a very short sleeve (e.g., 10mm) produces very small or no inner frictional resistance. The results also indicate that the inner frictional resistance develops rapidly with the sleeve length in dense sand than loose sand. Therefore, we recommend a use of a tall sleeve in loose sand while relatively a short sleeve in dense sand for effective use of the inner sleeve in mobilising inner frictional resistance.