This paper presents a comparison study for load-transfer characteristics of two different types of micropiles. In general, structural components of micropile are thread steel bar or hollow-steel-pipe and surrounding cement grouts and its bearing capacity is mostly estimated from frictional resistance between grouts due to the small tip diameter. In this study, compressive bearing characteristics of two types of micropiles are compared to each other. Two types are (1) thread bar reinforcement with gravity grouting and (2) hollow-steel-pipe reinforcement with pressure grouting using geotextile pack surround-ing micropile. Field test results showed that pressure-grouting micropile using geotextile pack provides better load transfer mechanism in that it makes surrounding soil strength to be fully mobilized upon load-ing.
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