The performance of grouted and un-grouted helical piles in sand

Abstract

Helical piles, which have been widely applied as a deep foundation system from small to large load ranges, are very suitable for different kinds of applications. Therefore, concerns about their axial qualification and quantification bearing capacities and performance characteristics seem to be warranted. Tests of full-scale axial compression and tension performed on large capacity helical piles sited in the sand deposit in Babolsar are reported in this study and considerations of design, procedures of installing and full-scale field load test results are discussed. The results in grouted and un-grouted conditions about axial static loading and tension on single-, double- and triple-helix helical piles indicated that in spite of unsuitable cylindrical performance of helical piles in sandy soil which was more confidence-based on resistance, axial compression resistance of the piles increased substantially after grouting, and grouting process had a slighter effect on tensile resistance.