Complete load transfer behavior of base-grouted bored piles

Abstract

A field study on the behavior of three destructive piles in soft soils subjected to axial load was presented. All the three piles with different diameters were base-grouted and installed with strain gauges along the piles. The complete load transfer behavior of the base-grouted pile was analyzed using measured results. Moreover, the thresholds of the relative pile-soil displacement for fully mobilizing skin frictions in different soils were investigated, and pile tip displacements needed to fully mobilize tip resistances were analyzed. The results of the full-scale loading tests show that the skin frictions are close to the ultimate values when the pile-soil relative displacements are 1%–3% of pile diameter, and the pile tip displacements needed to fully mobilize the tip resistances are about 1.3%–2.0% of pile diameter. The load transmission curve of the soils around the pile tip corresponds to a softening model when the pile is loaded to failure.

Keywords

destructive full-scale test / post-grouting technique / load-displacement response / axial force / tip resistance / skin friction

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