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http://dx.doi.org/10.7843/kgs.2015.31.2.27

Uplift Behavior of Group Micropile according to Embedded Pile Condition in Sand  

Kyung, Doo-Hyun (School of Civil and Environmental Engrg., Yonsei Univ.)
Kim, Ga-Ram (School of Civil and Environmental Engrg., Yonsei Univ.)
Park, Dae-Sung (School of Civil and Environmental Engrg., Yonsei Univ.)
Kim, Dae-Hong (KEPRI/KEPCO)
Lee, Jun-Hwan (School of Civil and Environmental Engrg., Yonsei Univ.)
Publication Information
Journal of the Korean Geotechnical Society / v.31, no.2, 2015 , pp. 27-37 More about this Journal
Abstract
The micropile is small diameter pile foundation of which diameter is below 300 mm. This system has been applied to reinforce the foundation structure. In the present study, the effects of embedded conditions of group micropiles were investigated from a series of uplift load tests. For the study, uplift load tests were performed using group micropiles in various pile spacing and installation angle. The increase of uplift resistance and the reduction of uplift displacement were investigated in the tests. As the result, the resistances were principally changed by embedded pile angle, the resistance increase were 33%, 59% and 5% for $15^{\circ}$, $30^{\circ}$ and $45^{\circ}$ of embedded pile angle. The uplift displacement reduction increases with lower pile spacing condition and the reduction ratios of uplift displacements in the same spacing condition were 50%, 53%, -45% for $15^{\circ}$, $30^{\circ}$ and $45^{\circ}$ of embedded pile angle.
Keywords
Micropile; Group micropile; Uplift load; Laboratory test; Sand;
Citations & Related Records
Times Cited By KSCI : 7  (Citation Analysis)
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